2008 florida bay and adjacent marine systems science conference

2008 Florida Bay and Adjacent Marine Systems

Science Conference

December 8-11, 2008

Naples Beach Hotel & Golf Club Naples, Florida, USA

PROGRAM AND ABSTRACT BOOK

Project # 0806

December 8-11, 2008 Naples, FL, USA

i

Welcome to the 2008 Florida Bay and

Adjacent Marine Systems Science Conference We would like to take this opportunity to welcome you to the 2008 Florida Bay and Adjacent Marine Systems Science Conference. We expect you will find this conference to be a wonderful opportunity to learn results of the most recent research in our South Florida estuarine and marine systems, and to strengthen the links between that research and the various ecosystem restoration projects being planned for South Florida. We also hope these next few days provide a time for you to sit down and exchange information and ideas with potential new colleagues, as well as with your established research partners. This conference provides numerous opportunities for exchange and interaction between those of you who manage the estuarine and marine resources of South Florida, and those of you who study them closely. Through all of these conversations, we hope to stimulate additional timely and focused research, as well provide the kind of environment where seeds of science-based management decision-making can begin to develop. This 2008 conference follows the lead and general format of previous Florida Bay conferences, with a few additions. We are a small group, and thus able to have everyone present and participating in every session—this is something we don’t necessarily want to change! We have conference themes similar to those of previous conferences; however, we have asked presenters to consider the implications of climate change in their work, and are sure this theme will gain in importance in the future. In addition, we have put more emphasis on clarifying resource management priorities as well as restoration issues that face Florida Bay and adjacent systems, and hope the initial presentations help set the stage for development of future research. Our sincerest appreciation goes to everyone who contributed toward the success of this event, especially to Patrick Pitts, who chaired the effort, and to the members of the Florida Bay Program Management Committee who worked hard to put it together, and to the University of Florida Office of Conferences and Institutes (OCI). We thank our invited plenary speakers and presenters of synthesis papers for agreeing to spend time to convey their information and set the direction for the next few days. And thanks of course to our attendees, without whom there would be no conference! Let’s enjoy the next few days of exchanging information here in southwest Florida, and return home with renewed enthusiasm and energy to provide the science needed to manage our bays and estuaries. Sincerely, The Co-Chairs of the Florida Bay Program Management Committee Carol L. Mitchell John Lamkin Deputy Director for Science SESFC SFNRC National Oceanic and Atmospheric Administration Everglades National Park

2008 Florida Bay and Adjacent Marine Systems Science Conference

ii


iii

Table of Contents

Welcome Letter ...................................................................................................... i

Program Development Committee .......................................................................v

Synthesis Development and Presentation ............................................................v

Scientific Oversight Panel ................................................................................... vi

Florida Bay Program Management Committee (PMC).................................. vii

Sponsor Recognition .......................................................................................... viii

Program Agenda .................................................................................................. ix

Poster Directory ................................................................................................ xvii

Symthesis Papers....................................................................................................1

Abstracts ...............................................................................................................41

Author Index ......................................................................................................169

Notes ....................................................................................................................172


iv


v

Program Development Committee We would like to thank the following individuals for reviewing abstract submissions and developing the program agenda. Richard Alleman

South Florida Water Management District, West Palm Beach, FL

Brian Keller NOAA Office of National Marine Sanctuaries, St. Petersburg, FL

John Lamkin NOAA Southeast Fisheries, Miami, FL

Patrick Pitts US Fish and Wildlife Service, Vero Beach, FL

David Rudnick South Florida Water Management District, West Palm Beach, FL

Jeff Woods US Geological Survey, Fort Lauderdale, FL

Mark Zucker US Geological Survey, Fort Lauderdale, FL

Synthesis Development and Presentation We would like to thank the following individuals for developing synthesis papers and creating a summary presentation for the general session. Benthic Habitats

Michael Durako, University of North Carolina, Wilmington, NC

Ecosystem History G. Lynn Wingard, US Geological Survey, Reston, VA

Higher Trophic Levels Joan Browder, NOAA Fisheries, Miami, FL

Mangrove Transition Zone Victor Rivera-Monroy, Louisiana State University, Baton Rouge, LA

Nutrient Dynamics / Algal Blooms David Rudnick, South Florida Water Management District, West Palm Beach, FL

Physical Processes Peter Ortner, NOAA/AOML, Miami, FL


vi

Scientific Oversight Panel (SOP) Independent expert review is an integral component of the Florida Bay and Adjacent Marine Systems Science Program. This need is served by a Science Oversight Panel (SOP) which participates in the conference by leading question and answer sessions and providing subsequent technical and management review of the quality of research, modeling and monitoring activities in Florida Bay and the scientific inferences from these activities. The SOP consists of six senior scientists with significant experience in major estuarine restoration programs. Please join us in thanking these individuals for the continued commitment to our program: Dr. William C. Boicourt

Horn Point Laboratory, Cambridge, MD Dr. Boicourt is a Professor of Physical Oceanography and specializes in physical oceanographic processes including circulation of the continental shelf and estuaries. Dr. William C. Dennison

University of Maryland Center for Environmental Science, Cambridge, MD Dr. Dennison is the Vice President for Science Applications at the University of Maryland, Center for Environmental Science. He is a marine ecologist with a specialty in ecophysiology of marine plants and has conducted coastal marine research in all of the world’s oceans. Dr. John E. Hobbie (Chair)

The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA Dr. Hobbie is a Senior Scholar at the Marine Biological Laboratory and is a microbial ecologist specializing in biogeochemical cycles of coastal and Arctic systems. Dr. Edward D. Houde

University of Maryland, Center for Environmental Science, Chesapeake Biological Laboratory, Solomons, MD

Dr. Houde is a professor at the University of Maryland and specializes in fisheries science, larval fish ecology, and resource assessment and management. Dr. Steven C. McCutcheon, P. E.

Faculty of Engineering, University of Georgia, Athens, GA Dr. McCutcheon, Past President of the American Ecological Engineering Society, is an expert in water quality management, hydrodynamics, hydrology, water resources, sediment transport, and hazardous waste management. Dr. Hans W. Paerl

Institute of Marine Sciences, University of North Carolina, Morehead City, NC Dr. Paerl is Kenan Professor of Marine and Environmental Sciences and his research includes nutrient cycling and production dynamics of aquatic ecosystems, environmental controls of algal production, and assessing the causes and consequences of eutrophication.


vii

Florida Bay Program Management Committee (PMC) Rick Alleman

South Florida Water Management District (SFWMD)

Rich Curry National Park Service (NPS) BISC

Scott Donahue National Oceanic and Atmospheric Administration (NOAA)

Kent Edwards Florida Department of Environmental Protection (FDEP), Florida Keys National Marine Sanctuary (FKNMS)

John Hunt Fish and Wildlife Commission (FWC)

Brian Keller National Oceanic and Atmospheric Administration (NOAA), Office of National Marine Sanctuaries

Bill Kruczynski Environmental Protection Agency (EPA)

John Lamkin National Oceanic and Atmospheric Administration (NOAA), Fisheries

Susan Markley Miami-Dade Department of Environmental Resources Management (DERM)

Carol Mitchell National Park Service (NPS), Everglades National Park

Bill Perry National Park Service (NPS), Everglades National Park

Patrick Pitts US Fish and Wildlife Service (USFWS)

Dave Rudnick South Florida Water Management District (SFWMD)

Brad Tarr US Army Corps of Engineers (USACE)

Jeff Woods US Geological Survey (USGS)

Mark Zucker US Geological Survey (USGS)


viii

Sponsor Recognition We kindly thank the partnering organizations for their continued support and commitment to the Florida Bay and Adjacent Marine Systems Science Program.

National Oceanic and Atmospheric Administration

National Park Service

South Florida Water Management District

University of Florida / IFAS

US Army Corps of Engineers

US Fish and Wildlife Service

US Geological Survey


ix

Program Agenda Meeting room locations are indicated at the end of events when applicable

[example: “…[Meeting Room 4]”]

Abstract page numbers are indicated at the end of listings when applicable [example: “…(p. 2)”]

Monday, December 8, 2008 5:00pm-8:00pm Welcome Social, Registration Opens & Poster Presenters Set-up Displays

Tuesday, December 9, 2008 7:15am-5:00pm Registration Office Open and Posters on Display 7:15am-8:00am Early Morning Refreshments 8:00am-8:10am Welcome and Official Opening — Carol Mitchell, Co-Chair, Florida Bay Program

Management Committee (PMC) and, Deputy Director for Science, South Florida Natural Resources Center, SFEO, Everglades National Park, Homestead, FL

8:10am-9:40am Session I – Potential Climate Change Impacts on Florida Bay and their Implications for Resource Managers MODERATOR: Carol Mitchell, Everglades National Park, Homestead, FL

8:10am-8:30am Florida Bay Resource Management Needs and Information for Resource Managers— Dave Hallac, Everglades National Park, Homestead, FL

8:30am-8:50am Climate Change Implications for Management of Chesapeake Bay — Bill Boicourt, University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge, MD

8:50am-9:10am Florida’s Wildlife: On the Front Line of Climate Change — Chuck Collins, Florida Fish and Wildlife Conservation Commission, West Pam Beach, FL

9:10am-9:30am Climate Change Implications for Management of Florida Bay — Carol Mitchell, National Park Service (NPS), Everglades National Park

9:30am-9:40am Discussion Panel with Speakers 9:40am-10:00am Refreshment Break & Networking

10:00am-12:30pm Session II – Synthesis Presentations MODERATOR: Susan Markley, Miami-Dade DERM, Miami, FL

10:00am-10:10am Opening Remarks and Session Overview by Moderator 10:10am-10:30am Ecosystem History — Lynn Wingard, US Geological Survey, Reston, VA ................(p. 9) 10:30am-10:50am Physical Processes — Peter Ortner, NOAA/AOML, Miami, FL.................................(p. 34) 10:50am-11:10am Nutrient Dynamics/Algal Blooms — David Rudnick, South Florida Water Management

District, West Palm Beach, FL.............................................................................................(p. 29) 11:10am-11:30am Benthic Habitats — Michael Durako, University of North Carolina, Wilmington,

NC...............................................................................................................................................(p. 5) 11:30am-11:50am Higher Trophic Levels — Joan Browder, NOAA Fisheries, Miami, FL...................(p. 15) 11:50am-12:10pm Mangrove Transition Zone — Victor Rivera-Monroy, Louisiana State University,

Baton Rouge, LA....................................................................................................................(p. 25) 12:10pm-12:30pm Discussion Panel with Speakers 12:30pm-1:30pm Group Luncheon.......................................................................................[Sunset Terrace]


x

Tuesday, December 9, 2008 (continued) 1:30pm-3:10pm Session III – Ecosystem History

MODERATOR: Lynn Wingard, US Geological Survey, Reston, VA 1:30pm-1:40pm Opening Remarks and Session Overview by Moderator 1:40pm-2:00pm Verification of a Molluscan Dataset for Paleosalinity Estimation Using Modern

Analogues: A Tool for Restoration of South Florida’s Estuaries — G. Lynn Wingard1 and Joel W. Hudley2; 1U.S. Geological Survey, Reston, VA, USA; 2University of North Carolina, Chapel Hill, NC, USA .................................................. (p. 160)

2:00pm-2:20pm A Comparison of the Pre-drainage Everglades Hydrology and Florida Bay Salinity Based on Paleoecology from Multiple Sediment Cores Coupled with Statistical Models — Frank E. Marshall1, G. Lynn Wingard2, Patrick Pitts3, Evelyn Gaiser4, Ania Wachnicka4;1Cetacean Logic Foundation, Inc., New Smyrna Beach, Florida, USA; 2US Geological Survey, Reston, Virginia, USA; 3US Fish & Wildlife Service, Vero Beach, Florida, USA; 4Florida International University, Miami, Florida, USA...................... (p. 131)

2:20pm-2:40pm Diatom-Based Inferences of Environmental Change in Florida Bay and Adjacent Coastal Wetlands of South Florida — A. Wachnicka1,2 and E. Gaiser3,2; 1Department of Earth Sciences, 2Southeast Environmental Research Center, 3Department of Biological Sciences, Florida International University, Miami, FL, USA....................................... (p. 156)

2:40pm-3:00pm Characterization of Natural Stream Flow in South Florida — Richard Alleman, South Florida Water Management District, West Palm Beach, FL, USA..................... (p. 43)

3:00pm-3:10pm Session Recap and Q&A with Presenters 3:10pm-3:30pm Refreshment Break and Networking

3:30pm-5:10pm Session IV Physical Processes MODERATOR: Jeff Woods, US Geological Survey, Fort Lauderdale, FL

3:30pm-3:40pm Opening Remarks and Session Overview by Moderator 3:40pm-4:00pm Determining Spatial and Temporal Inputs of Freshwater, Including Groundwater

Discharge, to a Subtropical Estuary Using Geochemical Tracers, Biscayne Bay, South Florida — Jeremy C. Stalker1, René M. Price2, Peter K. Swart3; 1Department of Earth Sciences, Florida International University; 2Department of Earth Sciences and the SERC, Florida International University; 3Marine Geology and Geophysics, RSMAS, University of Miami, Miami, FL, USA ............................................................................ (p. 151)

4:00pm-4:20pm Effects of Groundwater on Salinity in Biscayne Bay — Sarah Bellmund1, Greg Graves2, Steve Krupa2, Herve Jobert3, Greg Garis1, and Steve Blair4; 1Biscayne National Park Salinity Monitoring Program, Biscayne National Park, Homestead, FL, USA; 2South Florida Water Management District, West Palm Beach, FL, USA; 3Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA; 4Miami-Dade County Department of Resources Management, Miami, FL, USA................................ (p. 49)

4:20pm-4:40pm Surface Salinity Variability of South Florida Coastal and Estuarine Waters from Gridded Shipboard Observations, 1995 – 2008 — Elizabeth M. Johns1, Thomas N. Lee3, Christopher N. Kelble2, Ryan H. Smith1, Nelson Melo2, Peter B. Ortner2, and Vassiliki H. Kourafalou3; 1Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL, USA ; 2Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL, USA; 3Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA ................................................................................................................................ (p. 104)


xi

Tuesday, December 9, 2008 (continued) 4:40pm-5:00pm On Florida Bay Circulation and Water Exchange with Focus on the Western

Subregion — Thomas N. Lee1, Nelson Melo2, Ned Smith3, Elizabeth M. Johns4, Ryan H. Smith4, Christopher N. Kelble2, and Peter B. Ortner2; 1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 2Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL, USA; 3Harbor Branch Oceanographic Laboratory, Ft Pierce, FL, USA; 4Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL, USA.................................................................................................................................(p. 121)

5:00pm-5:10pm Session Recap and Q&A with Presenters 5:30pm-8:30pm POSTER SESSION & NETWORKING RECEPTION............... [Poster Display Area]

Wednesday, December 10, 2008 7:30am-5:00pm Registration Office Open 7:30am-8:30am Early Morning Refreshments 7:30am-5:00pm Posters on Display

8:30am-10:10am SESSION V – Physical Processes (continued) MODERATOR: Mark Zucker, US Geological Survey, Fort Lauderdale, FL

8:30am-8:40am Opening Remarks and Session Overview by Moderator 8:40am-9:00am South Florida Coastal Oceanographic Database — Nelson Melo1, Thomas N. Lee2,

Elizabeth M. Johns3, Ryan H. Smith3, Chris R. Kelble1, and Peter B. Ortner1; 1Cooperative Institute for Marine and Atmospheric Studies, U. of Miami, Miami, FL, USA; 2 Rosenstiel School of Marine and Atmospheric Science, U. of Miami, Miami, FL, USA; 3 NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, USA........................................................................................................................................(p. 137)

9:00am-9:20am Advection and Exchange in Florida Bay Inferred from Long-term Water Quality Data — B.J. Cosby1, J. Boyer2, H. Briceno2, F. Marshall3, and W. Nuttle4; 1University of Virginia, Charlottesville, VA, USA; 2Florida International University, Miami, FL, USA; 3Cetacean Logic Foundation, New Smyrna Beach, FL, USA; 4Eco-hydrology, Ottawa, ON, Canada.............................................................................................................................(p. 64)

9:20am-9:40am Enhancing and Combining Complex Numerical Models of Coastal Southern Florida — Eric Swain1, Melinda Lohmann1, and Jeremy Decker1; 1U.S. Geological Survey, Florida Integrated Science Center, Fort Lauderdale, FL, USA.....................................(p. 153)

9:40am-10:00am Interdisciplinary Modeling Support to CERP: Toward Environmental Prediction with the South Florida HYCOM System — Villy H. Kourafalou1, HeeSook Kang1, Claire Paris1, Chuanmin Hu2, Peter J. Hogan3 and Ole Martin Smedstad4; 1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 2Institute for Marine Remote Sensing, University of South Florida, St. Petersburg, FL, USA; 3Naval Research Lab, Stennis Space Center, MS, USA; 4QinetiQ North America, Technology Solutions Group – PSI, Stennis Space Center, MS, USA........................................................................................................................................(p. 119)

10:00am-10:10am Session Recap and Q&A with Presenters 10:10am-10:30am Refreshment Break and Networking


xii

Wednesday, December 10, 2008 (continued) 10:30am-12:10pm SESSION VI – Water Quality/Algae Blooms

MODERATOR: David Rudnick, South Florida Water Management District, West Palm Beach, FL 10:30am-10:40am Opening Remarks and Session Overview by Moderator 10:40am-11:00am A Synthesis of Models to Simulate Benthic-Pelagic Coupling in Florida Bay:

Examination of Ecosystem Restoration and Climate Change Effects — Christopher J. Madden1 Amanda A. McDonald1; 1Everglades Division, South Florida Water Management District, West Palm Beach, FL USA......................................................... (p. 129)

11:00am-11:20am Phosphorus Cycling in Florida Bay: A Synthesis — Marguerite S. Koch1, Ole Nielsen1, Henning S. Jensen2, Jia-Zhong Zhang3, Chris J. Madden4, Dave Rudnick4;

1Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA; 2Biology Department, University of Southern Denmark, Odense, Denmark; 3NOAA, Ocean Chemistry Division, AOML, Miami, FL, USA; 4Everglades Research Division, SFWMD, West Palm Beach, USA.................................................................................... (p. 118)

11:20am-11:40am Relative Importance of Solid-Phase Phosphorus and Iron on Sediment-Water Exchange of Phosphate in Florida Bay — Jia-Zhong Zhang1 and Xiao-Lan Huang1,2 ; 1Ocean Chemistry Division, Atlantic Oceanographic and Meteorological Laboratory; National Oceanic and Atmospheric Administration, Miami, FL, USA; 2CIMAS, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA........................................................................................................................................ (p. 164)

11:40am-12:00pm Nutrient Limitation in Benthic Microalgae in Florida Bay — Merrie Beth Neely1 and Gabriel A. Vargo1; 1University of South Florida College of Marine Science, St. Petersburg, FL, USA .......................................................................................................... (p. 142)

12:00pm-12:10pm Session Recap and Q&A with Presenters 12:10pm-1:30pm Group Luncheon ...................................................................................... [Sunset Terrace]

1:30pm-3:10pm Session VII – Water Quality/Algae Blooms (continued) MODERATOR: David Rudnick, South Florida Water Management District, West Palm Beach, FL

1:30pm-1:40pm Opening Remarks and Session Overview by Moderator 1:40pm-2:00pm In situ Measurements of Sponge Respiration, Nitrification and ANAMMOX on the

Florida Keys Reef Tract — Christopher S. Martens1, Niels Lindquist2, Patrick Gibson1, Howard Mendlovitz1, James Hench3 Brian Popp4, Richard Camilli5, Anthony Duryea6, Robert Byrne7, Lori Adornato8 and Xuewu Liu; 1Dept of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; 2Institute of Marine Sciences, UNC–Chapel Hill, Morehead City, NC; 3Dept of Civil and Environmental Engineering, Stanford University, CA; 4Dept of Geol&Geophys, University of Hawaii-Manoa, Honolulu, HI; 5Appl Ocean Phy&Eng, Woods Hole Oceanographic Institution, Woods Hole, MA; 6Monitor Instruments Company LLC, Cheswick, PA; 7College of Marine Science, University of South Florida, St Petersburg, FL; 8SRI International, St Petersburg, FL, USA ........................................................................................................... (p. 133)

2:00pm-2:20pm Dissolved Organic Material and the Adaptive Physiology of Synechococcus Help to Sustain Blooms in Florida Bay — Patricia M. Glibert1, Cynthia A. Heil2, Sue Murasko2, Jeffrey Alexander1, MerrieBeth Neely2, Christopher Madden3; 1 University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge MD, USA; 2 Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL; 3 Coastal Ecosystems Division, South Florida Water Management District, West Palm Beach, FL..................................................................... (p. 88)


xiii

Wednesday, December 10, 2008 (continued) 2:20pm-2:40pm Spatial and Temporal Shifts in Planktonic Phosphorus Limitation in Florida Bay

from 2002 to 2007 — Cynthia A. Heil1, Patricia M. Glibert2, Sue Murasko3, Jeff Alexander2, Merrie Beth Neely1, Ana Hoare3 and Chris Madden4; 1Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL; 2University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge MD, USA; 3College of Marine Science, University of South Florida, St. Petersburg, FL USA; 4Coastal Ecosystems Division, South Florida Water Management District, West Palm Beach, FL.............................................................................................(p. 96)

2:40pm-3:00pm Characterizing the Dynamics of Dissolved Organic Matter in the Florida Coastal Everglades — Rudolf Jaffé1,2, M. Chen1,2 , Y. Yamashita1,2, N. Maie1,2, K. Parish1,2, R. M. Price1,3, J. Boyer1, and L. Scinto1,4; 1 Southeast Environmental Research Center, Florida International University, Miami, FL, USA; 2 Department of Chemistry and Biochemistry, Florida International University, Miami, FL, USA; 3 Department of Earth Science, Florida International University, Miami, FL, USA; 4Department of Environmental Studies, Florida International University, Miami, FL, USA ..............(p. 102)

3:00pm-3:10pm Session Recap and Q&A with Presenters 3:10pm-3:30pm Refreshment Break and Networking

3:30pm-5:00pm Session VIII – Water Quality/Algae Blooms (continued) MODERATOR: David Rudnick, South Florida Water Management District, West Palm Beach, FL

3:30pm-3:50pm Storm Strength, Proximity, and Water Residence Time Differentially Affect the Magnitude of Impact and Recovery Time of Phytoplankton Biomass in Separate Zones of Florida Bay — Henry O. Briceño and Joseph N. Boyer, Southeast Environmental Research Center, Florida International University, Miami, FL, USA..........................................................................................................................................(p. 57)

3:50pm-4:10pm Coupled Hydrodynamic and Water Quality Modeling of Florida Bay — John M. Hamrick1 and Zhen-Gang Ji2; 1Tetra Tech, Inc., Fairfax, VA; 2Applied Environmental Engineering, LLC, Naples, FL..................................................................(p. 95)

4:10pm-4:30pm Remote Sensing of Water Quality Index in Florida Bay and Florida Keys: Current Status and Challenge — C. Hu,1 J. Cannizzaro,1 F. Muller-Karger,2 J. Hendee3, E. Johns3, L. Gramer,4 C. Kelble,4, N. Melo4; 1College of Marine Science, Univ. South Florida, St. Petersburg, FL, USA; 2School for Marine Science and Technology, Univ Massachusetts Dartmouth, New Bedford, MA, USA; 3Atlantic Oceanographic and Meteorological Lab, NOAA, Miami, FL, USA; 4Cooperative Institute for Marine and Atmospheric Studies, Univ. Miami, Miami, FL, USA.....................................................(p. 98)

4:30pm-4:50pm Marine and Estuarine Goal Setting for South Florida (MARES) — Peter B. Ortner1, Carol L. Mitchell2, Joseph N. Boyer3 and Christopher R. Kelble1;

1Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 2Southeast Environmental Research Center, Florida International University, Miami, FL, USA; 3South Florida Natural Resources Center, Everglades National Park, Homestead, FL, USA........................................................................................................................................(p. 111)

4:50pm-5:00pm Session Recap and Q&A with Presenters 5:30pm-8:30pm Networking Reception ................................................................................. [Ocean Lawn]


xiv

Thursday, December 11, 2008 7:30am-5:00pm Registration Office Open 7:30am-8:30am Early Morning Refreshments

8:30am-10:10am Session IX - Benthic Habitats MODERATOR: Brian Keller, NOAA Office of National Marine Sanctuaries, Southeast Region, St. Petersburg, FL

8:30am-8:40am Opening Remarks and Session Overview by Moderator 8:40am – 9:00am Climate Change Effects on Seagrass Multiple Stressors, Nutrient Cycling and

Reproduction: A Perfect Storm in Florida Bay? — Marguerite S. Koch, Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA................. (p. 116)

9:00am-9:20am Seagrass as Indicators of Ecosystem Change in South Florida Estuaries — M.O. Hall1, M. J. Durako2, M. Merello1, D. Berns1, J. Kunzelman1, K. Toth1 and M. Cristman3;

1Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL, USA; 2University of North Carolina at Wilmington, Wilmington, NC, USA; 3Department of Statistics, University of Florida/IFAS, Gainesville, FL, USA ........................................ (p. 91)

9:20am-9:40am Phosphorus Availability and Salinity Control Productivity and Demography of the Seagrass Thalassia testudinum in Florida Bay — Darrell A. Herbert1 and James W. Fourqurean1, 2;1Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL; 2Fairchild Tropical Botanic Garden, Coral Gables, FL ...................................................................................... (p. 97)

9:40am-10:00am Effects of Fertilization and Herbivory on Seagrass Community Structure in Florida Bay — Zayda Halun1 and James W. Fourqurean1; 1Department of Biological Sciences and Southeast Environmental Resource Center, Florida International University, Miami, FL, USA .................................................................................................................................. (p. 94)

10:00am-10:10am Session Recap and Q&A with Presenters 10:10am-10:30am Refreshment Break & Networking

10:30am-12:00pm Session X - Benthic Habitats (continued) MODERATOR: Brian Keller, NOAA Office of National Marine Sanctuaries, Southeast Region, St. Petersburg, FL

10:30am-10:50am Spatio-Temporal Dynamics of SAV Abundance in the Mangrove Lakes Region of Florida Bay: Relationships to Salinity, Phosphorus, and Water Clarity — Thomas A. Frankovich1, Douglas Morrison2, and James W. Fourqurean1; 1Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, USA; 2 Everglades National Park, Florida Bay Interagency Science Center, Key Largo, FL, USA........................................................... (p. 83)

10:50am-11:10am Multiple Lines of Evidence Suggest Long-term Eutrophication of Seagrass-dominated Nearshore Ecosystems in the Florida Keys — James W. Fourqurean, Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, USA........................................................... (p. 81)

11:10am-11:30am Déjà Vu All Over Again: The Impact of Recent Cyanobacteria Blooms on Hard-bottom Communities in Florida Bay and the Florida Keys — Mark J. Butler IV1 and Donald C. Behringer Jr.2 1 Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA; 2 Program in Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA ............................................................................................................ (p. 61)

11:30am-11:50am Monitoring Coral Bleaching as an Indicator of Climate Change Resilience for Florida’s Reefs — Chris Bergh, The Nature Conservancy, Summerland Key, FL, USA.......................................................................................................................................... (p. 50)

11:50am-12:00pm Session Recap and Q&A with Presenters


xv

Thursday, December 11, 2008 (continued) 12:00pm-1:30pm Group Luncheon.......................................................................................[Sunset Terrace]

1:30pm-3:10pm Session XI – Higher Trophic Level MODERATOR: John Lamkin, Florida Bay PMC Co-Chair, NOAA, Miami, FL

1:30pm-1:40pm Opening Remarks and Session Overview by Moderator 1:40pm-2:00pm Bottlenose Dolphin Research in both Florida and Biscayne Bays and the Use of

Dolphins as Indicators of Estuary Health — Jenny Litz1, Laura Engleby2, Joseph Contillo1, Lance Garrison1, John Kucklick3; 1NOAA, National Marine Fisheries Service, Miami, FL, USA; 2Dolphin Ecology Project, St. Petersburg, FL, USA; 3National Institute of Standards and Technology, Charleston, SC, USA .....................................................(p. 123)

2:00pm-2:20pm A Flood Tidal Transport for Pink Shrimp Larvae on the SW Florida Shelf — Maria M. Criales1, Joan A. Browder2 and Michael B. Robblee3; 1RSMAS, University of Miami, Miami, FL, USA; 2NOAA Fisheries, Miami, FL, USA; 3U.S. Geological Survey, Ft. Lauderdale, FL, USA.............................................................................................................(p. 66)

2:20pm-2:40pm Mercury Bioaccumulation in Florida Bay Fish: Why so High? — David W. Evans1 and Darren Rumbold2; 1NOAA, Center for Fisheries and Habitat Research, Beaufort, NC; 2Department of Marine and Ecological Sciences, Florida Gulf Coast University, Fort Myers, FL, USA .....................................................................................................................(p. 70)

2:40pm-3:00pm Variations in Carbon and Oxygen Stable Isotopes in the Otoliths of Four Species of Juvenile Snapper (Lutjanidae) in Florida Bay — Anne B. Morgan1, Trika L. Gerard2;

1Cooperative Institute for Marine and Atmospheric Science, Rosenstiel School of Marine and Atmospheric Science, University of Miami, FL, USA; 2NOAA-NMFS, Southeast Fisheries Science Center, Miami, FL, USA .....................................................................(p. 139)

3:00pm-3:10pm Session Recap and Q&A with Presenters 3:10pm-3:30pm Refreshment Break and Networking (Poster presenters to remove displays)

3:30pm-5:10pm Session XII – Higher Trophic Level (continued) MODERATOR: John Lamkin, Florida Bay PMC Co-Chair, NOAA, Miami, FL

3:30pm-3:50pm Concentration and Upstream Migration of Pink Shrimp Postlarvae in Northwestern Florida Bay — Maria M. Criales1, Joan A. Browder2, Michael B. Robblee3, Thomas Jackson2 and Hernando Cardenas1; 1RSMAS, University of Miami, Miami, FL; 2NOAA Fisheries, Miami, FL; 3U.S. Geological Survey, Ft. Lauderdale, FL .............................(p. 59)

3:50pm-4:10pm Contribution of Mangrove Nursery Habitats to Replenishment of Adult Reef Fish Populations in Southern Florida — David L. Jones1, John F. Walter2, and Joseph E. Serafy2; 1Cooperative Institute for Marine & Atmospheric Studies, University of Miami–Rosenstiel School, Miami, FL, USA; 2NOAA Fisheries, Miami, FL, USA ...............(p. 107)

4:10pm-4:30pm Relationship of Mesozooplankton to Water Quality in Florida Bay — Christopher R. Kelble1, Peter B. Ortner1, Gary L. Hitchcock2 and Michael J. Dagg3;

1Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 2Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 3Louisiana Universities Marine Consortium, Chauvin, LA, USA....................................................(p. 112)

4:30pm-4:50pm Monitoring Populations of Fish and Macroinvertebrates in Florida Bay — Matheson, Jr., R.E.1, K.E. Flaherty1, and R.H. McMichael, Jr.1; 1Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, St. Petersburg, FL, USA...................................................................................................................................(p. 73)

4:50pm-5:00pm Session Recap and Q&A with Presenters 5:00pm-5:10pm Closing Remarks and Conference Concludes


xvi


xvii

Poster Directory

Listing is in alphabetical order by presenting author last name. Abstract page numbers are indicated at the end of listings [example: “… (p. 2)”]

Poster No. 24..........A Review of Ruppia maritima in Relation to Salinity in Northeastern Florida Bay — Christian L.

Avila1 and Peter Frezza2; 1Miami-Dade Department of Environmental Resources Management (DERM), Miami, FL; 2Audubon of Florida, Tavernier Science Center, Tavernier, FL .............................................. (p. 45)

25..........Seagrass Communities of Biscayne Bay, 1999-2007 Miami-Dade County — Christian L. Avila, Stephen Blair, Sheri Kempinski, Santiago Acevedo and Jonathan Sidner1; 1 Ecosystem Restoration & Planning Division, Miami-Dade County Department of Environmental Resources Management. Miami, FL...... (p. 47)

27..........Effects of Light and Nutrient Supply on Stable Isotope Composition and Fractionation in N-Limited Seagrass Beds — Rebecca J Bernard1 and James W Fourqurean2; 1 Florida International University, Department of Biological Sciences, Miami, FL, USA; 2 Florida International University, Department of Biological Sciences and SERC, Miami, FL, USA........................................................................................... (p. 51)

26..........Recovery Status of Submerged Aquatic Vegetation in Manatee Bay, Barnes Sound and Northeastern Florida Bay Following Senescence of a Prolonged Algal Bloom — Stephen Blair1, David T. Rudnick2, Christian Avila1, Forrest Shaw1, Maurice Pierre1; Kathryne Wilson1 and Susan Markley1; 1 Ecosystem Restoration & Planning Division, Miami-Dade County Department of Environmental Resources Management. Miami, FL; 2 Everglades Division, South Florida Water Management District, West Palm Beach, FL............................................................................................................................................................... (p. 53)

13..........Nutrient Loading in the Coastal Creeks of Northeastern Florida Bay — Carrie Boudreau1, Mark Zucker1 and Jeff Woods1; 1U.S. Geological Survey, Florida Integrated Science Center, Ft. Lauderdale, FL, USA ........................................................................................................................................................................ (p. 55)

9............Species Composition of Cyanobacterial Blooms in Florida Bay — Joseph N. Boyer1, Makoto Ikenaga2, Amanda Dean1, and Cristina Pisani1; 1Southeast Environmental Research Center, Florida International University, Miami, FL, USA; 2Department of Life Science, Ritsumeikan University, Shiga, Japan...... (p. 56)

28..........Interspecific Variation in the Elemental and Stable Isotopic Content of Seagrass Communities in South Florida — Justin E. Campbell1, James W. Fourqurean1 ,1Florida International University, Miami FL ............................................................................................................................................................................ (p. 63)

18..........Florida Bay Salinity Extremes at Long Key — Andrew G. Crowder and Jonathan S. Fajans, SEAKEYS Monitoring Program, Florida Institute of Oceanograhpy, Long Key, FL, USA ......................................... (p. 68)

29..........Salinity, Light, and Temperature Effects on Ruppia maritima Germination in Florida Bay — Marguerite S. Koch1, Josh Filina1, Jackie Boudreau1, Stephanie Schopmeyer1, and Chris J. Madden2;

1Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA; 2South Florida Water Management District, West Palm Beach, FL, USA ........................................................................................ (p. 72)

34..........Enhancing Adaptive Management Processes through Data Integration and Visualization — Gregory Kiker1, James Hendee2, Yuncong Li3, Chuanmin Hu4, Pamela Fletcher5, Lew Gramer6; 1University of Florida, Gainesville, Florida, USA; 2NOAA/AOML, Miami, Florida, USA; 3University of Florida, Homestead, Florida, USA; 4University of South Florida, St. Petersburg, Florida USA; 5Florida Sea Grant, NOAA/AOML, Miami, Florida, USA; 6University of Miami, Miami, Florida, USA ............................... (p. 75)


xviii

Poster No. 22 ......... Halimeda Dynamics Relative to Nutrients Availability in the Florida Keys — Ligia Collado-Vides 1,2

and James W. Fourqurean1,2 ; 1Department of Biological Sciences; 2 Southeast Environmental Research Center, Florida International University, Miami, FL, USA ............................................................................(p. 77)

23 ......... Long-term Shifts in Seagrass Community Structure Follow Experimental Nutrient Enrichment in Florida Bay — Anna R. Armitage1, Thomas A. Frankovich2, and James W. Fourqurean2; 1Department of Marine Biology, Texas A&M University-Galveston, Galveston, TX, USA; 2Department of Biological Sciences and Southeastern Environmental Research Center, Florida International University, Miami, FL, USA .........................................................................................................................................................................(p. 79)

30 ......... Relationships Between Submerged Aquatic Vegetation Abundance and Salinity Variability within the Coastal Mangrove Zone of Northeastern Florida Bay — Peter Frezza and Jerome J. Lorenz, Audubon of Florida, Tavernier Science Center, Tavernier, FL......................................................................(p. 85)

1 ........... The Use of Otolith Microchemistry to Determine Sources of Lutjanid Recruits to the Dry Tortugas Ecological Reserve — T. Gerard 1 A. Wright 2 E. Malca 2, John Lamkin 1; 1National Oceanic and Atmospheric Administration (NOAA), Southeast Fisheries Science Center, Early Life History; Miami, FL; 2University of Miami, Cooperative Institute for Marine and Atmospheric Studies (CIMAS), Miami, FL.............................................................................................................................................................................(p. 86)

35 ......... Assessing Gaps in Florida’s Marine and Estuarine Conservation Network — Laura Geselbracht1 and Douglas Shaw2; 1The Nature Conservancy, Wilton Manors, FL, USA; 2The Nature Conservancy, Gainesville, FL, USA............................................................................................................................................(p. 87)

36 ......... WCA 3 Decompartmentalization and Sheetflow Enhancement Project Implications to Florida Bay — Brooke Hall1, Beth Marlowe2, Sue Wilcox2, and Tom St Clair3; 1Parsons, Everglades Partners Joint Venture, Jacksonville, Fl., USA; 2United States Army Corps of Engineers, Jacksonville, Fl., USA; 3PBS&J, Everglades Partners Joint Venture, Jacksonville, Fl., USA ............................................................................(p. 90)

19 ......... Patterns of Propeller Scarring of Seagrass in Florida Bay: Associations with Physical and Visitor Use Factors and Implications for Natural Resource Management — David E. Hallac, Jimi Sadle, Leonard Pearlstine, and Fred Herling, Everglades and Dry Tortugas National Parks, South Florida Natural Resources Center, Homestead, FL......................................................................................................................(p. 93)

37 ......... Minimum Inflow Analyses in Adjacent Systems: Why Are They Different? — Melody J. Hunt, Water Supply Department, South Florida Water Management District, West Palm Beach, FL, USA..............(p. 101)

17 ......... Biscayne Bay Salinity Monitoring Program — Sarah Bellmund1, Herve Jobert2, Greg Garis1, Steve Blair3, and Amy Renshaw4; 1Biscayne National Park, Homestead, FL, USA; 2Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA; 3Miami-Dade County Department of Environmental Resources Management, Miami, FL, USA; 4South Florida Natural Resources Center, Everglades National Park, Homestead, Fl, USA ............................................................................................(p. 103)

3 ........... Factors Affecting Seagrass and Mangrove Fauna Adjacent to the South Biscayne Bay Shoreline — Darlene R. Johnson1, Joan A. Browder2, Joseph E. Serafy2, Michael B. Robblee3, Thomas L. Jackson2, Gladys Liehr1, Eric Buck1, and Brian Teare1; 1CIMAS/RSMAS, University of Miami, Miami, FL, USA; 2Southeast Fisheries Science Center, National Marine Fisheries Service/ NOAA, Miami, FL, USA, 3United States Geological Survey, Center for Water and Restoration Studies, Everglades National Park Field Station....................................................................................................................................................................(p. 105)


xix

Poster No.

2............Juvenile Spotted Seatrout Power Analysis and Monitoring for Florida Bay — Christopher R. Kelble1, Clay E. Porch2, Allyn B. Powell3, Mike Lacroix3, Michael Greene3 and Joan Browder2; 1Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA; 2NOAA/NMFS Southeast Fisheries Science Center, Miami, FL, USA; 3NOAA Center for Coastal Fisheries and Habitat Research, Beaufort, NC USA...........................(p. 109)

11..........Interactive Effects of Eastern Florida Bay Algal Blooms and Lake Surprise Restoration: Timing is Everything — Stephen P. Kelly, Christopher J. Madden, David T. Rudnick and Kevin M. Cunniff, Everglades Division, Watershed Management Department, South Florida Water Management District, West Palm Beach, FL, USA...............................................................................................................................(p. 114)

8............Phycobilin Analysis Protocol Development for Ground-truthing Cyanobacterial Field Monitoring in Florida Bay and Adjacent Marine Systems — J. William Louda1, Stephen P. Kelly2 and Panne Mongkhonsri1; 1Organic Geochemistry Group, Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL; 2Everglades Division, South Florida Water Management District, West Palm Beach, FL..........................................................................................................................................(p. 125)

7............Pigment-based Chemotaxonomy of Florida Bay Phytoplankton and the Influences of Photic Flux — J. William Louda, Cidya S. Grant and Panne Mongkhonsri; Organic Geochemistry Group, Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL..............................................(p. 127)

21..........Florida Bay Seagrass Dynamics: A Modeling Study of Interspecific Competition, Salinity, and Nutrient Control — Amanda A. McDonald1, Christopher J. Madden1, and Marguerite S. Koch2;

1Everglades Division, South Florida Water Management District, West Palm Beach, FL, USA; 2Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA..............................................(p. 135)

14..........South Florida Coastal Oceanographic Database — Nelson Melo1, Thomas N. Lee2, Elizabeth M. Johns3, Ryan H. Smith3, Chris R. Kelble1, and Peter B. Ortner1; 1Cooperative Institute for Marine and Atmospheric Studies, U. of Miami, Miami, FL, USA; 2 Rosenstiel School of Marine and Atmospheric Science, U. of Miami, Miami, FL, USA; 3 NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, USA .......................................................................................................................................................................(p. 137)

31..........The Non-Native Red Rimmed Melania (Melanoides tuberculatus) in Biscayne Bay National Park, Florida, the Geographic Distribution and Potential for the Future — James B. Murray1, G. Lynn Wingard1, Emily Phillips1, William B. Schill2; 1U.S.Geological Survey, Reston, VA, USA; 2U.S. Geological Survey, Leetown Science Center, WV, USA ..................................................................................................(p. 140)

33..........Evaluating Alternative Plans for the Biscayne Bay Coastal Wetlands Project — Patrick Pitts1, Rick Alleman2, Mark Shafer3, Kevin Wittman3, Ernie Clarke3; 1U.S. Fish and Wildlife Service, Vero Beach, Florida, USA; 2South Florida Water Management District, West Palm Beach, Florida, USA; 3U.S. Army Corps of Engineers, Jacksonville, Florida, USA.............................................................................................(p. 143)

10..........Geochemical and Nutrient Concentrations in the Florida Bay Groundwater — René M. Price1, Jeremy C. Stalker1, Xavier Zapata-Rios1, Jean l. Jolicoeur2, David T. Rudnick3; 1 Florida International University, Department of Earth Sciences and SERC, Miami, FL, USA; 2 Broward Community College, 3 South Florida Water Management District, West Palm Beach, FL, USA...................................................(p. 145)

5............Regional Patterns of Community Composition and Abundance of Seagrass-associated Fish and Invertebrates in South Florida Estuaries — Michael B. Robblee1, Joan A. Browder2, Andre Danielś1 and Robert M. Dorazio3; 1U.S. Geological Survey, Miami, FL; 2NOAA Fisheries, Miami, FL; 3U.S, Geological Survey, Gainesville, FL..................................................................................................................(p. 147)


xx

Poster No.

6 ........... Use of Habitat Suitability Index Modeling for both Roseate Spoonbills (Ajaia ajaia) and American Crocodiles (Crocodylus acutus) in South Florida — F.J. Mazzotti1, S.S. Romanach2, J.J. Lorenz3, K.L. Chartier1, M.S. Cherkiss1, and L.A. Brandt4; 1 University of Florida, Fort Lauderdale Research and Education Center, Davie, FL, USA; 2 US Geological Survey, Davie, FL, USA; 3 Audubon of Florida, Tavernier, FL, USA; 4 US Fish and Wildlife Service, Davie, FL, USA .....................................................(p. 149)

32 ......... Benthic Habitat Mapping in Biscayne National Park — Benjamin I. Ruttenberg1, Andrea Atkinson1, Andy Estep1, Judd Patterson1, Matt Patterson1, Robert Waara1, Brian Witcher1, and Elsa Alvear2; 1U.S. National Park Service, South Florida/Caribbean Network, Palmetto Bay, FL USA; 2Biscayne National Park, Homestead, FL USA.................................................................................................................................(p. 150)

15 ......... Examining Submarine Groundwater Discharge into Florida Bay using 222Rn and Continuous Resistivity Profiling — Peter W. Swarzenski1, Chris Reich2, and David Rudnick3; 1U.S. Geological Survey, Santa Cruz, California; 2U.S. Geological Survey, St. Petersburg, FL; 3South Florida Water Management District, West Palm Beach, FL ..................................................................................................(p. 155)

20 ......... Effects of Habitat Complexity and Nutrient Enrichment on Epifauna Abundance and Diversity in a Florida Bay Seagrass System — C. A. Weaver1, A. R. Armitage1 and J. W. Fourqurean2; 1Department of Ecosystem Science and Management, Texas A&M University, College Station, TX, USA; 2Department of Biological Sciences, Florida International University, Miami, FL, USA ...................................................(p. 157)

4 ........... Understanding Ecosystem-scale Connectivity: Methods to Track Fish from Open-ocean to Nursery Habitats to Adjacent Reefs and Back Again — S. Whitcraft1, J. Lamkin2, T. Gerard2, and E. Malca1;

1Cooperative Institute for Marine & Atmospheric Science, University of Miami, Miami FL, USA .....(p. 159)

12 ......... Power Analysis of Water Quality and Seagrass Monitoring in Caloosahatchee Estuary — Deo Chimba and Jing-Yea Yang, Stanley Consultants Inc., West Palm Beach, Florida ................................................(p. 162)

16 ......... Quantity, Timing, and Distribution of Freshwater Flows into Northeastern Florida Bay, 1996-2007 — Mark Zucker1, Stephen Huddleston1, and, Jeff Woods1; 1U.S. Geological Survey, Florida Integrated Science Center, Ft. Lauderdale, FL, USA........................................................................................................(p. 166)

1

Synthesis Papers


2


3

Synthesis Papers We would like to thank the following individuals for developing synthesis papers and creating a summary presentation for the general session. Benthic Habitats

Michael Durako, University of North Carolina, Wilmington, NC...........................................5

Ecosystem History G. Lynn Wingard, US Geological Survey, Reston, VA............................................................9

Higher Trophic Levels Joan Browder, NOAA Fisheries, Miami, FL..........................................................................15

Mangrove Transition Zone Victor Rivera-Monroy, Louisiana State University, Baton Rouge, LA..................................25

Nutrient Dynamics / Algal Blooms David Rudnick, South Florida Water Management District, West Palm Beach, FL ..............29

Physical Processes Peter Ortner, NOAA/AOML, Miami, FL...............................................................................34


4


5

Rabbit Key Basin

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Mea

n Fr

eque

ncy

of O

ccur

renc

e (+

SE)

0.0

0.2

0.4

0.6

0.8

1.0

ThalassiaHaloduleSyringodium

Benthic Habitats in Florida Bay Michael J. Durako1, M. O. Hall2, M. J. Butler3 and D. C. Behringer4

1Department of Biology and Marine Biology, University of North Carolina Wilmington, Wilmington, NC, USA 2Florida Fish and Wildlife Research Institute, St. Petersburg, FL, USA 3Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA 4Program in Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA

Florida Bay is comprised of a series of shallow basins separated by a network of reticulating mudbanks and interspersed mangrove islands. Seagrass habitats of variable density and usually reduced canopy height dominate the spatially complex mudbanks. Mudbank sediments are dominated by carbonate mud, sand, or in the western portion of the Bay gravel. Sediment depth within the basins decreases across the Bay in a southwest to northeast gradient, thus hard-bottom habitat is extensive in the northeast Bay. Hard-bottom habitat is also common along the southern fringe of Florida Bay, adjacent to the Florida Keys. Hard-bottom is characterized by shallow sediments (< 5 cm) overlying Pleistocene limestone bedrock and sessile animal and plant communities of varying biodiversity that include: hard corals (e.g., Siderastrea, Porites and Solenastrea), soft corals (e.g., Pterogorgia anceps, Pseudopterogorgia spp.), sponges (> 25 species, including massive species such as the loggerhead sponge, Spheciospongia vesparium), lithophytic and calcareous green (e.g., Halimeda, Penicillus and Acetabularia) and red (e.g., Laurencia spp.) macroalgae, among other taxa. Sparse-to-dense seagrass patches occur in sediment-filled karst solution depressions in the bedrock of hard-bottom habitats. Several northern basins, adjacent to the Everglades, and deeper areas, along the western boundary of the Bay, contain areas of carbonate mud with high organic and water contents. Some of these ‘open-mud’ habitats lack vegetation or benthic fauna and they are frequently turbid due to wind, wave and current-induced resuspension. The shallow nature of Florida Bay (mean depth < 2m) generally allows for high light availability to the benthos, thus supporting extensive seagrass and macroalgae communities. Seagrass beds form the dominant and most widespread benthic habitats across the Bay, although drift red algae (Laurencia, Gracilaria, etc.) and siphonaceous (Caulerpa spp.) or calcareous (Halimeda, Penicillus, Udotea) green algae are also widespread. Of the more than 20,000 Braun-Blanquet

samples (each 0.25 m2) taken in Florida Bay from 1995-2008 by the Fisheries Habitat Assessment Program (FHAP), more than 95% contained seagrass, with Thalassia testudinum being the most dominant of the six seagrasses (Halodule wrightii, Syringodium filiforme, Ruppia maritima, Halophila engelmannii, and H. decipiens) occurring in the Bay. FHAP data also show that both Halodule and Syringodium have become more widspread and abundant, especially in the western basins

(Fig. 1), while Thalassia has declined in some central and eastern basins. Recent declines in Thalassia generally coincide with increases in Halodule indicating a shift to a more shade-adapted euryhaline seagrass community

Figure 1. Frequency of occurrence of Thalassia, Halodule, and Syringodium in Rabbit Key Basin from 1995 to 2007.


6

(Fig. 2). The observed changes are consistent with landscape-scale model predictions regarding benthic habitat distributions in response to water quality changes and increases in freshwater delivery to Florida Bay. Seagrasses account for the major portion of the Bay’s primary productivity and form the base of much of the Bay’s food web. They are also the principal habitat for the Bay’s higher trophic levels, particularly many commercially and recreationally important fish and invertebrate species. Other economically important species, including many that eventually recruit to coral reefs in the adjacent Florida Keys ecosystem (e.g., Caribbean spiny lobster, Panulirus argus; red grouper, Epinephelus morio; Nassau grouper, Epinephelus striatus) prefer Laurencia-dominated hard-bottom as nurseries. Red macroalgae and its detritus form the base of the trophic web in hard-bottom habitats, which appear to be largely independent of allochthonous seagrass production. Because of Florida Bay’s shallow depths, seagrasses are the dominant submerged physical feature in the Bay and their presence affects physical, chemical, geological and biological processes in this system (e.g., currents, nutrient cycling, sediment stabilization and enhanced biodiversity). As perennial clonal plants, seagrasses integrate net changes in water quality parameters (e.g., salinity, nutrient levels, and clarity) which tend to fluctuate widely when measured directly. Thus, changes in seagrass distribution and abundance are perceived as representative of changes in the overall health of the Florida Bay ecosystem. Widespread die-off of seagrasses, principally Thalassia, was first observed in Florida Bay in the late 1980’s, following a period of unusually high water temperatures and salinities. By 1990, 4000 ha of seagrass habitat was completely lost and 24,000 ha were affected by the die-off. This massive loss of the dominant benthic habitat in Florida Bay resulted in a cascade of ecological disturbances, including widespread and recurring phytoplankton blooms, dominated by the cyanobacteria Synechococcus, which were first observed in the fall of 1991. The Bay’s sponge communities, the majority of which lie in hard-bottom habitat, have proven to be especially sensitive to the blooms which have caused recurrent and widespread sponge die-offs. The loss of sponge habitat has in turn lead to losses of many other invertebrates, including juvenile lobsters, which depend on sponges for shelter. These ecosystem changes prompted the development of a model of Florida Bay - Florida Keys hard-bottom habitat and spiny lobster recruitment that has been used to predict their response to blooms and altered salinity. In 2002, a hard-bottom monitoring program that tracks the density and size structure of many sessile and some motile species was established by Old Dominion University and the Florida Fish and Wildlife Conservation Commission (FWCC) with sites in southern Florida Bay and the Florida Keys.

Figure 2. Braun-Blanquet abundance of Thalassia, Halodule, and Syringodium in Madeira Bay from 1995 to 2007.

M adeira Bay

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007

Mea

n B

raun

-Bla

nque

t Abu

ndan

ce (+

SE)

0

1

2

3

4ThalassiaHaloduleSyringodium


7

Phytoplankton blooms have also decreased water clarity leading to secondary mortality of seagrasses. Loss of seagrass habitat results in increased sediment resuspension producing a negative feedback loop. During the time period from 1992 to 1995, there was much speculation regarding how much benthic habitat had been lost and the reduced water clarity precluded remote sensing approaches to survey habitat distributions. Thus, FHAP was initiated by the FWCC during the spring of 1995. Benthic habitat in ten basins, representative of the varying conditions across Florida Bay has been sampled by FHAP every year since 1995. As a component of CERP’s Monitoring and Assessment Program (MAP), the geographic scope of FHAP was expanded in 2005 to include 22 sampling areas extending from Lostman’s River to northern Biscayne Bay (Fig. 3) and the program was renamed the South Florida Fish Habitat Assessment Program (FHAP-SF). FHAP-SF sampling has shown that Thalassia-dominated seagrass habitats are the most abundant benthic habitats in Florida Bay and southern Biscayne Bay. In contrast, Syringodium and Halodule are dominant in northern Biscayne Bay; the Biscayne Bay region also has widespread hard bottom habitats. Seagrass habitat is neither abundant nor widespread in the basins in the Southwest Region. Thalassia and Syringodium are almost totally absent in the southwest region;

Halodule and H. decipiens are the most common seagrasses in this region, but calcareous and coenocytic green algae are more widespread. The large green macroalgae Chara forms the most abundant habitat throughout Coot Bay and it is common in Whitewater Bay. Persistent Synechococcus blooms have been present in eastern Florida Bay and southern Biscayne Bay since 2005, following a relatively active hurricane season, and in central Florida Bay since the summer of 2007. Photophysiological data from FHAP-SF indicates that Thalassia in bloom-affected areas has exhibited significant changes in photoacclimation in the last 3 years (Fig. 4) and reduced optical water quality created by the blooms has decreased seagrass habitat in deeper portions of eastern basins. The recent blooms have also resulted in renewed mass mortality of sponge communities in the south-central Bay

Figure 3. FHAP-SF sampling polygons within three geographic regions.

Figure 4. Relationship between effective quantum yield (ΔF/Fm’, mean ± s.e.) and photosynthetically active radiation (PAR, μmoles quanta m-2 s-1) in Blackwater Sound during the 2006, 2007 and 2008 FHAP-SF spring sampling.

Blackwater Sound

PAR

0 200 400 600 800 1000 1200 1400 16000.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

2006 2006 Regr2007 2007 Regr20082008 Regr

2006y = -0.58e-4x + 0.79r2 = 0.48

2007y = -2.88e-4x + 0.82r2 = 0.61

Δ F/F

m'

2008y = -1.71e-4 + 0.72r2 = 0.43


8

and Florida Keys (Fig. 5), although other hard-bottom fauna, such as hard and soft corals and tunicates seem relatively unaffected. Juvenile lobster abundances, habitat use, and patterns of aggregation have again been impacted by the loss of sponge habitat. The recent increase in frequency of hurricanes, which may be a result of global climate change, seems to be at least partially responsible for some of the observed recent losses of benthic species. Hurricane-induced losses of benthic habitats may be direct, such as those due to wave effects, which erode sparse seagrass beds and may dislodge large sponges, or indirect, such as mortality due to reductions in salinity (physiological stress), sediment resuspension (light limitation), or nutrient increases (phytoplankton blooms leading to light limitation or sponge mortality). Anthropogenic activities that similarly affect water quality may exacerbate these indirect effects. Because of the exponential decrease in light with increasing depth, even small climate-change induced increases in sea level or anthropogenically-caused reductions in optical water quality could exacerbate benthic habitat losses in this region due primarily to light limitation because of the relatively high light requirements of seagrasses and symbiont-containing corals. Likewise, as evidenced by recent increases in coral bleaching, even small increases in water temperatures resulting from global warming may have negative effects on benthic species living near their upper thermal tolerance limits. Contact Information: Michael J. Durako, University of North Carolina Wilmington, Department of Biology and Marine Biology, Center for Marine Science, 5600 Marvin Moss Ln, Wilmington, NC 28409, USA, Phone: 910-962-2373, Fax: 910-962-2410, Email: [email protected]

Figure 5. At left, a diagram showing the locations and basic sampling framework of the pre- and post-bloom hard-bottom surveys conducted in 2007-2008. A summary of the impact of the 2007 central bay bloom on sponge communities on sites in south-central Florida Bay and adjacent Florida Keys is presented at top right. Moderate impacts or no impacts on the sponge communities were observed at sites lying nearer the periphery of the blooms (bottom right).


9

Ecosystem History of Florida Bay and the Southern Estuaries - Five-Year Update G. Lynn Wingard

U.S. Geological Survey, Reston, VA, USA Ecosystems develop over time-scales that exceed human history, so in order to restore or rehabilitate an ecosystem, it is essential to understand the long-term patterns and drivers of ecosystem change. Without this long-term perspective it would be impossible to set realistic and attainable performance measure targets required for the Everglades and adjacent ecosystems by the Comprehensive Everglades Restoration Plan (CERP). In 2003, a report was prepared for the Florida Bay Program Management Committee (later published as Wingard, 2007) that summarized the research and findings on the ecosystem history of Florida Bay. Significant progress has occurred during the last five years in our understanding and interpretation of the ecosystem history of Florida Bay, through detailed new analyses and synthesis of the initial results. In addition, the investigation has been expanded to examine a regional view of the southern estuaries, including Biscayne Bay and the southwest coastal region. The need to understand the long term patterns of change throughout south Florida has become even more evident to society at large in light of the Intergovernmental Panel on Climate Change (IPCC 2007) report, which contains forecasts of future climate change and sea level rise. South Florida has experienced repeated sea-level oscillations over the last 1.8 million years due to naturally occurring climatic cycles and these are preserved in the sedimentary record of south Florida. Information about past sea-level changes and their impacts provide valuable information about what impacts future sea-level rise may have. The primary emphasis of ecosystem history research since 2003 has been focused on addressing Question 1 of the Florida Bay Science Strategic Plan (see Hunt and Nuttle, 2007, p. 2): “How and at what rates do storms, changing freshwater flows, sea level rise, and local evaporation and precipitation influence circulation and salinity patterns within Florida Bay and exchange between the bay and adjacent waters?” In addition to paleoecological reconstructions in Florida Bay, new sediment cores have been collected and efforts have expanded into Biscayne Bay and the southwest coastal area, enabling the development of a regional picture of significant changes to the ecosystem over time. The USGS paleoecology group conducted additional research on cores discussed in the 2003 report and developed methods and analogue data sets to improve interpretations of past sea-level and environmental changes. Synthesis of Age Data for Estuaries One of the first steps in compiling and synthesizing the data was to refine the age interpretation of the cores collected between 1994 and 2003 (Wingard et al., 2007). Fifteen cores had been analyzed for reconstructing estuarine ecosystem history, but various methods and laboratories had been used for chronologic analysis. Consequently, cores were re-sampled for material for radiocarbon-14 dating, new dates were obtained, and age models were developed by integrating all age data for each core. The methodology involved a mixed effect regression model that examines the variance between samples (depth and time) and the variance within each sample (sample thickness and probable age range). The output produces an estimated age-depth curve with a 95% confidence interval (Heegaard and others, 2005).


10

For eleven of the fifteen cores, the start of 20th century deposition could be indentified with relative accuracy (+/- 5-10 cm). This time period is significant because it is generally accepted that most human alteration of the Everglades ecosystem occurred in the 20th century. The pre-20th century age models for the cores are more difficult to frame with confidence due to factors involved in dating young sediments with carbon-14 and also due to carbon reservoir effects in carbonate-rich south Florida (see Wingard et al., 2007 for detailed discussion).

Salinity Patterns in the Estuaries The revised age models were used to interpret regional temporal and spatial changes in salinity patterns within south Florida estuaries using salinity sensitive indicator species and assemblages of mollusks (USGS, unpublished results)(Figure 1). The results indicate that salinity was gradually increasing in the near-shore areas of Florida Bay, Barnes Sound, and Card Sound and in parts of Biscayne Bay prior to the beginning of the 20th century, which is consistent with estimates of relative sea level rise based on tidal gauges. Around 1900, these estuaries exhibited typical patterns of zonation, grading from polyhaline (18-30 ppt) to euhaline (30-40 ppt) salinities in the outer estuaries and oligohaline (<5 ppt) to mesohaline (5-18 ppt) in the transition zones nearshore. By the end of the 20th century, however, these typical zonations had disappeared in Florida Bay (Figure 1), and large areas in the central portion of the bay contained euryhaline faunal assemblages, generally low in diversity and containing species tolerant of wide fluctuations in salinity. Cores have been collected from eleven sites in the southwest coastal area since 2003. Eight of these cores form transects up Shark River, Harney River, and Lostmans River that have the potential to document changes in the dynamics between freshwater outflow through the Shark River Slough and marine influx. Preliminary examination of these cores, indicates that during the time of deposition, the Lostmans system was less influenced by freshwater flow and more emergent than the two systems to the south (Wingard et al., 2005 and 2006). Freshwater flow has periodically reached the mouths of the Harney and Shark River systems, but these areas have persistently been zones of mixed estuarine environments, typical of transition zones. Cores collected from the mid-point on the Harney and Shark River transects indicate a substantial change occurred in the flow regime, with a shift towards more estuarine conditions and a loss of freshwater fauna in the upper portions of the cores. New Tools for Interpreting Ecosystem History In 2005, the Southern Estuaries Sub-team of RECOVER (Restoration Coordination & Verification) expressed concerns about the disparity between salinities predicted for Florida Bay and Biscayne Bay by the Natural Systems Model (NSM) developed by South Florida Water Management District versus the paleosalinity estimates based on sediment core data. Models are valuable tools for analyzing hydrodynamic conditions within the wetlands and estuaries of south Florida and allow resource managers to look at changes on a variety of time scales – daily, monthly, seasonal and longer-term. A common criticism of models, however, is that they are not based on empirical data. Paleoecologic methods provide empirical data on salinity, but due to time-averaging, constraints of age models and other inherent problems, the paleo-record is generally limited to decadal-scale resolution of salinity patterns.


11

Outer estuarine salinity

Innerestuarine salinity

Minimumextent of

freshwater

Freshwater

A. ~ 2000 years before present B. ~1900 AD

C. 2000 AD

Figure 1. Illustration of the changing salinity patterns in Florida Bay and Biscayne Bay from ~ 2000 years before present to the present, based on faunal assemblages from cores. A. The minimum extent of freshwater ~2000 years ago extended past the current terrestrial margin. B. Around the beginning of the 20th century, the estuaries showed a typical zonation moving from more saline towards less saline approaching the nearshore transition zone. The gradual increase in salinities seen between 2000 yrbp and 1900 AD is consistent with rising sea level. C. The present day system shows a loss of the typical estuarine zonation in Florida Bay during the 20th century. Central Florida Bay and the nearshore areas are dominated by a low diversity euryhaline assemblage that can tolerate a wide range of salinities.

Outer estuarine salinity

Nearly Marine

Nearly Marine

Euryhaline

Innerestuarine salinity

Euryhaline & outer

estuarine

A collaborative effort formed to couple paleoecologic data to linear regression models and thus overcome the problems associated with both methods. The method involves three phases (see Marshall et al., this volume; Marshall et al., in review). First, paleoecologic analyses are conducted on an estuarine core to determine the salinity regime for the pre-disturbance environment (~1900 AD). A critical part of this step is to adjust the NSM to the salinity regime for the 1900 time frame in order to produce simulated daily and seasonal salinity values. In


12

phase two, linear regression equations are derived from modern empirical data in the freshwater Everglades (flow and stage) and the estuaries (salinity). These equations predict the salinity within the estuary, given a stage height (or flow) within the wetlands. The final phase couples the simulated paleo-salinity regime with the equations to produce estimates of flow, stage, and hydroperiod in the historical Everglades wetlands. The initial analysis used paleo-data from the USGS Whipray Basin core (central Florida Bay), and the results indicate that pre-disturbance flows through Shark River Slough were 2 to 3 times greater than today, and through Taylor Slough were almost 4 times greater than today (Marshall et al., in review). The largest flow deficits occurred in the dry season. Average pre-disturbance salinities were 12 to 20 ppt lower in the nearshore areas than modern salinities. These results and additional planned analyses provide a valuable tool for setting performance measures and targets for hydrodynamic conditions in the wetlands and in the estuaries. Several quantitative salinity data sets have been developed and/or refined since 2003. FIU researchers have analyzed diatom assemblages in a number of cores throughout the south Florida ecosystem. A multi-taxon diatom prediction model, using weighted averaging partial least squares regression, is used to determine ecological changes, including salinity, in sediment cores (see Wachnicka and Gaiser, this volume). USGS researchers developed the cumulative-weighted percent (CWP) salinity function based on modern-analogue molluscan data collected throughout the southern estuaries of the Everglades ecosystem (see Wingard and Hudley, this volume). The CWP method was tested on a modern data set and the results can predict average salinity at ~2-year intervals with a correlation coefficient of 0.8 to 0.9. Both of these quantitative methods (diatom and mollusk based) can be used in conjunction with the coupled linear regression models or can be used alone to interpret core results. Summary and Next Steps Significant progress has been made in our understanding of the ecosystem history of Florida Bay, Biscayne Bay and the other estuaries of south Florida since the 2003 report (Wingard, 2007). The addition of new information from Biscayne Bay and the southwest coastal region is expanding our understanding of the regional scale processes affecting the estuaries, including sea-level rise and anthropogenic alterations. The coupling of paleoecologic data with models represents an important break-through in overcoming past obstacles to understanding historical seasonal patterns, and the interaction between the wetlands and the estuaries. These advances provide the CERP teams with a realistic view of the historical greater Everglades Ecosystem, and provide the information necessary to set targets and performance measures for restoration. The next steps in ecosystem history research include the following:

1) Reevaluate existing USGS cores using cumulative weighted percent method and molluscan salinity analogue data set so smaller-scale shifts in salinity patterns over time will be revealed, and each sample will have an associated confidence level.

2) Generate additional coupled linear regression / paleoecology models for other cores from southern estuaries (Marshall in collaboration with USGS and FIU).

3) Complete detailed analyses of USGS southwestern cores.

4) Calculate recent rates of sea level rise and project rates into future based on various IPCC scenarios for the 21st century. Develop the capability to forecast what this means in terms of


13

salinity and flow and the implications for the restoration of the Everglades and Florida’s southern estuaries.

5) Compile information from Florida Bay, Biscayne Bay and the southwest coastal area to develop a regional overview of change in south Florida estuaries over the last 100-1000 years, and attempt to determine which components of change are caused by alterations of natural flow, versus large-scale factors such as sea-level rise and climate change.

Results from this proposed work would refine our models of past conditions in the estuaries, and allow us to estimate the future impacts of rising sea level in the context of restoration efforts. In addition, large scale paleoecologic, paleoclimatologic, and paleoceangraphic research going on outside the scope of CERP will provide valuable insights into past conditions and future conditions of south Florida under various IPCC (2007) scenarios for the 21st century (see discussion in Willard and Cronin, 2007). References: Heegaard, E., Birks, H.J.B. & Telford, RJ. 2005. Relationships between calibrated ages and depth in stratigraphical

sequences: an estimation procedure by mixed-effect regression. The Holocene 15: 612-618. Hunt, J.H., and Nuttle, W. 2007. Florida Bay Science Program: A Synthesis of Research on Florida Bay: Fish and

Wildlife Research Report, Technical Report 11. Intergovernmental Panel on Climate Change (IPCC). 2007. Climate change 2007; The physical science basis;

Contribution of Working Group I to the Fourth assessment report of the IPCC: New York, Cambridge University Press, 996 p., 1 CD–ROM. [Available at http://www.ipcc.ch/ipccreports/ar4-wg1.htm]

Marshall, F.E., Wingard, G.L., and Pitts, Patrick. In Review. A Simulation of Historic Hydrology and Salinity in Everglades National Park: Coupling Paleoecologic Assemblage Data with Regression Models, Manuscript submitted to Estuaries and Coasts, the Coastal and Estuarine Research Federation, 46 msp.

Marshall, F.E., Wingard, G.L., Pitts, P., Gaiser, E., and Wachnicka, A. 2008. Comparison of the Pre-drainage Everglades Hydrology and Florida Bay Salinity Based on Paleoecology from Multiple Sediment Cores Coupled With Statistical Models: Florida Bay Program and Abstracts (Proceedings) of the 2008 Florida Bay and Adjacent Marine Systems Science Conference, Dec. 8-11, 2008, Naples, Florida.

Wachnicka, A. and Gaiser, E. 2008. Diatom-Based Inferences of Environmental Change in Florida Bay and Adjacent Coastal Wetlands of South Florida: Florida Bay Program and Abstracts (Proceedings) of the 2008 Florida Bay and Adjacent Marine Systems Science Conference, Dec. 8-11, 2008, Naples, Florida.

Willard, D.A. and Cronin, T.M. 2007. Paleoecology and ecosystem restoration: Case studies from Chesapeake Bay and the Florida Everglades: Frontiers in Ecology and the Environment, v. 5, n. 9, p. 491-498.

Wingard, G.L. (with contributions by T.M. Cronin and W. Orem). 2007. Ecosystem History, Chapter 3, in Hunt, J.H., and Nuttle, W. (eds.), Florida Bay Science Program: A Synthesis of Research on Florida Bay: Fish and Wildlife Research Report, Technical Report 11, p. 9-29.

Wingard, G.L., Budet, C., Ortiz, R., Hudley, J.W., and Murray, J.B. 2006. Descriptions and Preliminary Report on Sediment Cores from the Southwest Coastal Area: Part II Collected July 2005, Everglades National Park, Florida: U.S. Geological Survey, OFR 2006-1271, 33 p. [Available at http://sofia.usgs.gov/publications/ofr/2006-1271/]

Wingard, G.L., Cronin, T.M., Holmes, C.W., Willard, D.A., Budet, C., and Ortiz, R. 2005. Descriptions and Preliminary Report on Sediment Cores from the Southwest Coastal Area, Everglades National Park, Florida: U. S. Geological Survey, Open File Report 2005-1360, 28 p. [Available at http://sofia.usgs.gov/publications/ofr/2005-1360/]

Wingard, G.L., and Hudley, J.W. 2008. Verification of a molluscan dataset for paleosalinity estimation using modern analogues: a tool for restoration of south Florida’s estuaries. Florida Bay Program and Abstracts (Proceedings) of the 2008 Florida Bay and Adjacent Marine Systems Science Conference, Dec. 8-11, 2008, Naples, Florida.


14

Wingard, G.L., Hudley, J.W., Holmes, C.W., Willard, D.A., and Marot, M. 2007. Synthesis of age data and chronology for Florida Bay and Biscayne Bay Cores collected for the Ecosystem History of South Florida’s Estuaries Projects: U. S. Geological Survey, Open File Report 2007-1203. [Available at http://sofia.usgs.gov/publications/ofr/2007-1203/index.html]

Contact Information: G. Lynn Wingard, Eastern Earth Surface Processes Team, U.S. Geological Survey, MS 926A National Center, 12201 Sunrise Valley Drive, Reston, VA, 20192, USA, Phone: 703-648-5352, Fax: 703-648-6953, Email: [email protected]


15

Update and Synthesis of Higher Trophic Levels Research in Florida Bay, 2003 to Present Joan A. Browder

NOAA, National Marine Fisheries Service, Southeast Fisheries Science Center, Miami, FL Dead seagrass and algal blooms called national attention to Florida Bay in the late 1980s and early 1990s. The existing water management system, with its canals and levees, was identified as a likely cause for damaging Florida Bay and other systems by disrupting the natural hydrologic process linking rainfall to freshwater flow to estuaries. A series of ensuing events and communications led to formation of the Intergovernmental Task Force for South Florida Ecosystem Restoration and development of the Comprehensive Everglades Restoration Plan (CERP). Concern for Florida Bay generated funding for an unprecedented concentration of scientific effort in the bay that included investigations of what has been termed the “Higher Trophic Level” (HTL) component. A Florida Bay Synthesis report released in 2007 covered Florida Bay research from the early stages of the South Florida ecosystem restoration initiative through about 2003 and included an HTL chapter. This abstract picks up the topic there and brings it forward to present. As in the previous synthesis, HTL refers to all fauna, from lowest faunal taxa to highest. Sources of Florida Bay research were found in the funding programs of most federal and state agencies partnering in the South Florida Ecosystem Restoration Initiative through the Intergovernmental Task Force and the Comprehensive Ecosystem Restoration Project (CERP) (Table 1). Scientific efforts are focused on determining the relationships between faunal populations and features and conditions of their inshore habitat that support them in order to predict how habitat and associated fauna might be affected by hydrologic changes brought about by CERP, Modified Water Deliveries, C111-Spreader Canal, and other ongoing water management projects that will affect freshwater flow to Florida Bay. CERP is intended to restore the Florida Bay ecosystem by creating a more natural quantity, quality, timing, and distribution of freshwater inflow to the Bay. Both the precise definition of restoration and the evidence that restoration has occurred lie primarily with the fauna. What scientists can learn about faunal habitat requirements in time to affect planning and how scientists evaluate the spatial and temporal patterns of abundance obtained from monitoring are of primary importance in both guiding and evaluating the restoration process. The HTL science conducted in Florida Bay since 2003 is both a continuation and expansion of previously existing projects and projects on new topics. As before, the body of HTL science is based on field studies, laboratory experiments, systematic monitoring, and modeling. The CERP Monitoring and Assessment Plan (MAP) is a major source of support for accumulating scientific information on Florida Bay higher trophic level species. RECOVER, the planning, organizing, coordinating, and communicating science body of CERP, is made up of interagency science teams that develop and implement the MAP. Guided by RECOVER, MAP presently is providing the quantitative basis for describing pre-CERP conditions while, at the same time, generating a database that, along with historic data, is being analyzed to populate and enrich the knowledge framework for evaluating monitoring results and making assessments. FIAN (Fish and Invertebrate Assessment Network) (USGS and NMFS, Robblee and Browder 2008) is a current MAP project providing a first-ever regional view of the abundance and community composition of seagrass-associated benthic epifauna across South Florida estuarine


16

environments, from Biscayne Bay, through Florida Bay to the mangrove estuaries of the southwest coast. Using the 1-m2 throw-trap across all areas, FIAN provides a broad overview of fish and invertebrate (shrimp and crabs) densities in relation to habitat features and conditions potentially influenced by CERP, such as salinity and SAV. The project links by methodology and location to historical studies dating from 1983. FIAN will quantify status and trends in the nearshore epibenthic fish and shrimp communities with in relation to CERP. Particular interest currently is focused on the pink shrimp, Farfantepenaeus duorarum. The project has found that species composition differs substantially between the southwest coast and the other two systems. Critical to CERP because the pink shrimp is a RECOVER indicator species, FIAN is quantifying for the first time the contrasting relationships of pink shrimp to salinity in two different South Florida environments, western Florida Bay (moderate-, low-variability-salinity) and Whitewater Bay (low-, highly-variable-salinity); juvenile pink shrimp are found in greatest abundance in western Florida Bay, however densities are higher in Whitewater Bay than in most other South Florida estuarine environments sampled. Findings such as these identify future research needs. The southwest coast mangrove areas downstream from Shark River Slough may be the first to experience the effects of CERP implementation, yet this area has been poorly covered by recent work. Two research efforts in this area are particularly important. Under MAP, Florida Gulf Coast University (Volety et al. 2008) is mapping and describing for the first time the living and relic oyster reefs of the Lower Southwest Coast from the Harney to Chatham Rivers and the conditions under which they thrived. The project has found substantial intertidal oyster bar development, especially in the Broad and Chatham Rivers. While the Whitewater Bay to Ponce de Leon Bay system was also a part of the project, limited living and relic oyster beds were found there in this project, perhaps because they are subtidal rather than tidal, or perhaps because of conditions at the time of year that the aerial survey was made (June instead of January). Chatham River has the most extensive oyster bar development, with locations throughout the estuary from the inner bays seaward to the mouth. In Lostmans and Broad Rivers, oyster development is primarily at the mouths. The difference in distribution is likely due to the difference in the freshwater flow regime in the three systems. An interesting project observation is that the Ten Thousand Islands geomorphology and that of the mangrove estuaries of Everglades National Park differ substantially. Oyster bar formation has led to a progradation of the Ten Thousand Islands despite the late Holocene sea-level rise, but this phenomenon is absent from Everglades National Park. The breakpoint between the two types of systems is at Chatham River, which has a geomorphology more similar to that of the Ten Thousand Islands. Two desired project outcomes are 1) a view of conditions that established and maintained oyster bars in the past, which would provide perspective on the flow regimes of the natural system, and 2) a view of the flow regimes that are maintaining oyster bars in the present system, which may provide further guidance on the flow regimes required for a restored natural ecosystem. The combined action of hurricanes, sea level rise, and changes in water management may be converting mangrove forest areas of the lower southwest Florida coast to mud flats. The purpose of a USGS study in the Big Sable Creek area of the Everglades National Park (ENP) was to determine the biological consequences of such habitat conversion (Silverman et al. 2006, Silverman 2006). The study quantified the density of fish and decapod crustaceans in the two habitat types. Block nets were placed across replicate intertidal rivulets draining both forested and mudflat sites to passively collect fish and decapods on ebbing spring tides. The research team found that when corrected for water volume, fish densities and biomass were much higher in forested wetlands compared to bare tidal flats, and community composition differed


17

significantly in the two habitats. Small schooling fish predominated on the mudflats, whereas mojarra and grass shrimp comprised 85% of organisms captured in the forest. Some work started at about the same time as the South Florida Ecosystem Restoration Initiative in the mid 1990s has continued through today. This includes the spiny lobster work by Old Dominion University (ODU)(Butler), University of Florida (Behringer), the Florida Fish and Wildlife Conservation Commission (Hunt), and others; the collaborative postlarval pink shrimp immigration work by University of Miami, NMFS, and USGS (Criales, Browder, and Robblee); and the juvenile spotted seatrout work, started by NOAA/NMFS (Powell) and continuing as a RECOVER monitoring project in collaboration of NOAA/NMFS (Browder) with the NOAA agency of Oceanic and Atmospheric Research (OAR, Kelble). Since its development in the 1990s as part of the NOAA Coastal Ocean Program, the NMFS pink shrimp simulation model (Browder et al. 1999, 2002) has had several applications to Florida Bay and other south Florida estuaries. The continuation of established projects has contributed substantially to our knowledge of Florida Bay and valuable ecological indicators. ODU has continued to sharpen the connection between lobsters and sponges and between sponge die-off and algal blooms. Butler’s investigation of the most recent phytoplankton bloom in southeastern Florida Bay strengthened the evidence of the algal bloom-sponge die-off connection. Criales et al. (2005, 2006, 2007) identified the most probable pathways of immigration of pink shrimp larvae from Tortugas spawning grounds to Florida Bay and described and quantified the potential effect of the most likely facilitating process--selective tidal stream transport (demonstrated for the first time across a broad shelf rather than at the edge of an estuary). Investigation of postlarval movement into the interior of the bay was the next phase of this project, and present work is examining postlarval settlement. Promising analyses by Powell and Lacroix (NMFS) suggest that juvenile spotted seatrout abundance in northcentral Florida Bay (i.e., Rankin Lake and Whipray Basin) is enhanced by a breakdown in the hypersaline conditions that often persist in the area (Powell 2008). A multidisciplinary collaboration of UM/RSMAS, NMFS, and ODU (Jones, Lara, Lamkin, Chen) is studying the habitat affinities of snapper species often found in estuaries during part of their life cycle. A study of gray snapper and two other lutjanid species demonstrates that otolith microchemistry has great promise in identifying the specific estuarine nursery sites that support these species (Jones et al. Submitted). Such a linkage will help scientists pinpoint the specific locations and conditions contributing most strongly to recruitment to fishable populations inshore and on the nearshore reefs. The study shows that gradients of microelements established by freshwater inflow, mixing with Gulf of Mexico and Atlantic Ocean waters, and differential use of spot locations by roosting or nesting water birds provide distinguishable signatures reflected in the otoliths of the lutjanids, although different signatures are found between two species collected from the same location (i.e., gray and schoolmaster and gray and yellowtail), possibly because of differences in microhabitat usage or food. Fishes could be assigned to originating nursery habitat with an 82% success rate (Lara et al., In prep). Another otolith study by the same group (UM/RSMAS, Wright et al. 2008) is determining the concentration of δ13C and δ18O stable isotopes in the otoliths of four snapper species found in Florida Bay. Carbon isotopes are determined by several, mostly metabolic factors, while oxygen isotopes reflect ambient water conditions. The otolith studies are among several projects by the group that apply technological advances such as microchemistry, stable isotope analysis, and tagging to relate fishery species to nursery grounds. Determining the specific conditions of salinity and other


18

variables affected by water management will help evaluate the effects of CERP on these important sites supporting fishery populations of snapper and other species. Field-based studies relating abundance and species composition to salinity and other variables have been complemented by laboratory exposure tests. Under Critical Ecosystem Studies Initiative (CESI) funding, the Florida International University Ecotoxicology Laboratory (Bachmann and Rand, in press) described the survival rates of four small fish species common to estuaries under salinity regime scenarios including abrupt change from 30-ppt salinity to target lower salinities from 15 to 0 ppt (essentially mesohaline), gradual change from 30 ppt to the same target lower salinities, and gradual change from estuarine conditions to the same target lower salinities. In 10-day survival tests, Gary Rand and staff determined that the mosquitofish (Gambusia holbrooki) (10% mortality after 10 days) had the highest tolerance to abrupt salinity change from polyhaline to mesohaline, whereas the goldspotted killifish (Floridichthys carpio) had the lowest tolerance (100% mortality after 10 days). A gradual change from 30 ppt down to target lower salinities (15 through 0 ppt) resulted in no mortality in three of the four species, but 50% mortality in 0 ppt at 72 hrs in F. carpio. A gradual change from 15 ppt to 0 ppt resulted in no mortality in 96 hrs for three of the species and 50% mortality in F. carpio. Other species studied were sheepshead minnow (Cyprinodon variegates) and sailfin molly (Poecilia latipinna). Clearly, F. carpio is the more sensitive species to either abrupt or gradual decrease in salinity, regardless of starting salinity. This study provides information that can be used to predict how these four common species of South Florida coastal wetlands and estuaries will respond to planned or proposed water management changes that will affect salinity patterns. In trials with hypersalinity to 60 ppt, the native strain of C. variegates was unaffected but growth slowed at 60 ppt in a laboratory strain of the same species. In another case in which laboratory studies complement field studies, USGS (Schofield) explored the basis of habitat partitioning by two goby species common to Florida Bay, the code goby and the clown goby, Gobiosoma robustum and Microgobius gulosa. The laboratory work suggested that both species preferred lower salinities and that the use of bare versus vegetated bottom habitat varied between species only when the amount of vegetated habitat was restricted (and only for M. gulosa in the presence of G. robustum, the competitively dominant species) (Schofield (2003a). Apparently, vegetated habitat was preferred by both species. Choice of bare or vegetated habitat had no effect on predation by the Gulf toadfish, Opsanus beta, although M. gulosa had the higher probability of being eaten, even though M. gulosa is a burrowing species, whereas G. robustum is not (Schofield 2005). Both species exhibited their highest growth rate at 5 ppt, compared to 35 ppt, in laboratory trials (Schofield 2004). Survival was 100% over 240 hours for G. robustum at 10, 15, and 30 ppt and significantly lower at 0 ppt and 60 ppt. Survival was 100% over 240 hours for M. gulosus at 5, 10, 15, and 30 ppt and significantly depressed at 0, 50, and 60 ppt (Schofield 2003b). The code and clown gobies, while not the most abundant fish in south Florida estuaries, are among the top species making up species composition in resource surveys of Florida Bay and western nearshore South Biscayne Bay. As such, they have been the topic of single-species analyses (i.e., Generalized Additive Models, Multiple Linear Regression) to determine the influence of salinity and habitat on density. Both NMFS (Browder) and ODU (Butler) previously have conducted laboratory studies to define optima and/or tolerance limits for the indicator species pink shrimp and spiny lobster. Additionally, ODU has produced salinity tolerance limits for sponges, which are essential functional components of the habitat of spiny lobster.


19

Both the ODU lobster laboratory experiments and the NMFS pink shrimp laboratory experiments have been used in setting the parameters of predictive models. The ODU model (Butler 2003, Butler et al. 2005) is an individual-based lobster model, and the NMFS pink shrimp model is a growth and survival simulation model (1999, 2002). The lobster model demonstrates the population-level consequences of large-scale processes in interaction with small-scale, spatially specific details of habitat quality. Its results argue for the use of a model, in place of intuition, to evaluate the effect of various influences, such as a change in salinity regime, on a population. The NMFS model, by means of several applications (Browder and Johnson 2008) has shown how the potential production of pink shrimp by a nursery area could vary based on salinity regime (either different regimes among areas or a change in regime within an area caused by a change in water management structure and operation, as in CERP). On the basis of the laboratory experiments, the ODU model used 35 ppt as the optimal salinity for juvenile lobster, whereas the NMFS model used 30 ppt as the optimal salinity for juvenile pink shrimp. Habitat Suitability Indices (HSI) are another type of model being developed for application to Florida Bay and are the present emphasis of the CESI Program. The Audubon of Florida Tavernier Science Center, along with Cadmus Group (Lorenz, Bartell, Nuttle) are developing an HSI model for roseate spoonbill nesting in northeastern Florida Bay and feeding in the coastal freshwater wetlands north of the bay. Basically an index of nest production, this HSI is based on three critical parameters that determine feeding patterns: prey availability, prey abundance, and distance from the colony to foraging locations. A set of wetland hydrology and estuarine salinity models were implemented to support the initial application of this HSI model. These associated models link to regional hydrologic scenarios defined by the output of the South Florida Water Management Model (SFWMM) to provide predictions of the effects of CERP on the eastern Florida Bay roseate spoonbill population. Prey abundance is based on a regression model of fish standing stock as a function of seven variables of salinity and water depth. A strong regression relationship (r2=0.32, p<0.0001) was determined from data collected by Lorenz in 19 years (1990-1998) of fish community sampling at four stations (Bartell et al. 2005). The HSI is applied to each 400 m x 400 m cell of a landscape grid. Water depth is calculated on the 400-m grid based on predictions of the hydrologic models at the Everglades National Park wells CP (Craighead Pond) and EPSW, observed fluctuations in sea level in Florida Bay, and the relation of water level at these three locations to ponding depth in each grid cell, as inferred from aerial surveys. In addition to Audubon’s long-term roseate spoonbill data, this project was founded on multi-year sampling of the fish community in the coastal freshwater marsh and mangrove forest ecotone upstream from Florida Bay and Barnes Sound, which was used by Lorenz and Serafy (2005) to define the salinity range of occurrence for many fishes of coastal wetland habitats. UM RSMAS and ENP teamed up on developing HSI models for several fishery and forage species found in Florida Bay primarily in their juvenile stage (Ault et al. 2005). The models are based on field data from Charlotte Harbor and Biscayne Bay; however, collection of new fishery-independent data from Florida Bay is a part of the study. The Charlotte Harbor data are from the Florida Fish and Wildlife Research Institute (FWRI) and have previously been applied to HSI modeling in Rookery Bay by FWRI (Rubec). Applying a delta-density approach, two models are developed for each species, a model of occurrence and a model of catch-per-unit-effort (CPUE), or density, at sites of occurrence. Results of the two models are combined to produce the predictions. Their predictions for juvenile spotted seatrout show low-density patches of juvenile density in western and eastern Florida Bay in June 2001 and high density patches of juvenile seatrout in the western, central, and eastern bay in September 2001. While the predictions for the western bay conform to Powell’s work, the patches of seatrout in the


20

eastern bay are contrary to Powell (2003), who found few seatrout postlarvae at his eastern Florida Bay stations and confined later sampling to the central and western bay. In another CESI-funded study to produce an HSI model, University of Florida (UFL) (Mazzotti) is monitoring the nesting ecology, growth, and survival of crocodiles in the northeastern part of Florida Bay to establish a baseline under current water management conditions for later comparisons after CERP implementation. Past research suggests that crocodile populations would benefit from restoring early dry season freshwater flows to Florida Bay and Biscayne Bay. The UFL researchers defined 20 ppt as the salinity threshold for juvenile crocodile survival. Several studies have examined the factors that influence immigration of larvae and the spatial distribution of settlement in inshore waters. Clemson University (Zito and Childress 2007) has documented the presence of the Allee effect in spiny lobster. Researchers have found that larval survival and population growth rate are positively related to adult density. Olfactory cues may guide lobster larvae to sites densely populated with adult lobster. This effect is thought to ensure reproductive success in sessile invertebrates, but its fitness benefits for a mobile invertebrate such as the spiny lobster is not known. The investigators speculate that it may lead to selection of high quality habitat that provides easy access to food and shelter. Butler (undated) described the nursery habitat of spiny lobster. Lobster postlarvae settle initially in structurally complex vegetation in hardbottom habitat, seagrass beds, or mangrove prop roots. Three or four months after they metamorphose, they become social and move to sponges and similar types of structure.The banks that surround most of Florida Bay restrict the ingress of lobster larvae, and juveniles are found only on the southeastern side of the bay, where channels through the Keys provide access to larvae and hardbottom habitat is conducive to survival. The lethal virus that strikes juvenile lobster is another factor that affects the spatial distribution of juvenile lobsters By means of complementary field and laboratory studies, ODU and UFL investigators ((Behringer et al. 2008) determined that infected individuals are avoided by their healthy congeners, which affects the spatial pattern of abundance. The disease, PaV1, appears to strike most severely juvenile lobsters at the stage where they are associated with structure such as sponge in hardbottom habitat (Butler et al., in press). Hardbottom provides nursery habitat not only for spiny lobster but also for other species. In a Florida Wildlife Legacy project, Tellier et al. (2008) found that the majority of sessile invertebrate structure or hardbottom habitat was composed of sponge and octocoral taxa. The abundance of decapods, including spiny lobster (Panulirus argus) and Florida stone crab (Menippe mercenaria), both valuable commercial species, was correlated with sponge abundance, whereas the abundance of other invertebrate taxa was correlated with the abundance of echinoderms and octocorals. The investigators noted that hardbottom also serves as habitat for juvenile fish. These investigators defined three distinct nearshore hardbottom communities in the Florida Keys area: Oceanside, Channels, and Inner Bay. The centrally positioned Outer Bay region was not distinguishable from any other geographic region. Based on what is known so far about its inhabitants, hardbottom communities could be detrimentally affected by water management choices that reduce salinities in hardbottom areas. These areas are removed from any direct freshwater inflow influences; however, they could be affected by change in freshwater flow of a magnitude that affects circulation patterns. Baywide models that link salinity patterns to freshwater outflows (e.g., the Environmental Fluid Dynamics Code, EFDC) could potentially show the extent of exposure to a lower salinity regime in the various hardbottom areas of the southern bay under various water management scenarios.


21

A joint study by UM/RSMAS, NMFS, and USGS (Criales et al. 2005, 2006, 2007) has identified selective tidal stream transport (STST) as the behavioral mechanism acting in concert with the tides to transport larval pink shrimp from offshore spawning grounds to inshore nursery grounds. The proposed route is from southwest to northeast across the southwest shelf into western Florida Bay. These investigators have recently addressed the question of whether the abundance of pink shrimp in Florida Bay’s interior is limited by postlarval transport or by extremes of salinity. Based on larvae collections in summer- fall of 2004 and 2005 along a six station transect, they determined that the highest concentrations of postlarvae occurred, not at the boundary of the bay, but at two mid-transect stations located about 15 km into the bay in shallow channels surrounded by dense seagrass beds and moderate tidal amplitude (15-20 cm) (Criales et al. 2008). Moving beyond these stations to the two easternmost stations, concentrations exhibited a marked decrease concurrent with a reduction of the tidal amplitude (≈1 cm) and an increase in salinity and temperature. Apparently access to the bay’s interior is restricted, and the environment found on arrival is not always hospitable to young pink shrimp ready to settle. This suggests that the salinity regime in the westernmost part of the interior bay (i.e., the water areas in the vicinity of Snake Bight, Joe Kemp, Palm, Murray, and Johnson Keys), where postlarvae are present in great numbers, may be of major importance to the shrimp population that supports the Tortugas fishing grounds because the postlarvae enter this area in great numbers. On the other hand, salinity conditions in the more eastern interior bay (i.e., from the vicinity of Buoy Key eastward) may be of less consequence to this population because transport of settlement-stage pink shrimp postlarvae into this area probably is inconsistent. Continuing and newly initiated research is sharpening our understanding of the processes that shape the ecology of Florida Bay and the influence of salinity and other aspects of habitat on the distribution and abundance of faunal species and communities of interest as indicators. Recent research has provided substantially more insight into the factors that influence abundance and distribution. This information is essential to interpreting monitoring results in CERP and making accurate assessments of CERP impacts. In terms of specific thresholds, preferences, or optima for individual species that can be directly used in evaluation of alternative CERP scenarios, only the FIU salinity tolerance experiments as yet provide new information beyond that cited in the original synthesis. Future work should focus especially on acquiring and improving specific information about the relationship of species and communities to salinity, as well as other potential influencing factors (e.g., nutrients, turbidity) on faunal species and communities that may be changed by CERP. More experiments should be conducted to define tolerances and other responses over a range of salinities, as well as to salinity fluctuations. The effect on growth and survival of the upper end of existing salinities in South Florida was considered in only one species in the FIU study, and one especially common species, Lucania parva (rainwater killifish), was not studied. More research and monitoring attention should be given to the lower southwest Florida coast, especially to those areas that will be influenced by changes in flow patterns through Shark River Slough.


22

Table 1. Funding sources and programs for Higher Trophic Level science in Florida Bay.

Agency Funding vehicle or source Florida Fish and Wildlife Conservation Commission (FFWCC) Legacy, other? National Park Service (NPS) CESI U.S. Geological Survey (USGS) CERP MAP, CESI NOAA National Marine Fisheries Service (NMFS) NOAA EFH, COP, CERP MAP NOAA Oceanic and Atmospheric Research (OAR) NOAA OAR, CERP MAP South Florida Water Management District (SFWMD) CERP MAP, FBFKFS U.S. Army Corps of Engineers (USACE) CERP MAP Old Dominion University (ODU) FFWCC University of Miami Rosenstiel School of Marine and Atmospheric Science (UMRSMAS) NOAA COP, EFH

Florida International University (FIU) NPS CESI Florida Gulf Coast University (FGCU) CERP MAP University of Florida (UFL) FFWCC, Legacy Audubon of Florida Tavernier Research Center (TRC) CERP MAP Everglades National Park (ENP) NPS CESI Clemson University FFWCC

Acronyms used and not defined above: CERP = Comprehensive Everglades Restoration Project CESI = Critical Ecosystems Initiative, EFH = Essential Fish Habitat COP = Coastal Ocean Program FBFKFS = Florida Bay-Florida Keys Feasibility Study NOAA = National Oceanic and Atmospheric Administration

Literature Cited: Ault, J. S., S. G. Smith, and W. B. Perry. 2005. NPS/CESU Technical report: Fishery rsource habitat use modeling

in Florida Bay: development and applications to Everglades restoration implementation (phase I). Final report to National Park Service on Cooperative Agreement No. H500000B494-15280040007 from the University of Miami Rosenstiel School of Marine and Atmospheric Science.

Bachmann, P. M., and G. M. Rand. In press. Effects of salinity on native estuarine fish species in South Florida. Ecotoxicology.

Bartell, S. M., J. J. Lorenz, W. K. Nuttle. 2005. Ecological models for ENP evaluation of CERP activities: roseate spponbill habitat suitability model: nesting success in Florida Bay. Report to Everglades National Park from The Cadmus Group, Inc., the National Audubon Society, and William Nuttle. 47 pp.

Behringer, D. C., M. J. Butler IV, and J. D. Shields. 2008. Ecological and physiological effects of LaV1 infection on the Caribbean spiny lobster (Panulirus argus Latreille). Journal of Experimental Marine Biology and Ecology 359:26-33.

Browder, J. A. and D. R. Johnson. 2007. Pink shrimp populations in the Florida Bay/Florida Keys regions: model of pink shrimp growth, survival, and recruitment. Report 3 to the South Florida Water Management District, West Palm Beach, FL (Agreement #4600000633), from NOAA National Marine Fisheries Service, Southeast Fisheries Science Center, Miami, FL (PRBD-07/08-08. 32 pp.

Browder, J.A., Z. Zein-Eldin, M.C. Criales, M.B. Robblee, and T.L. Jackson. 2002. Dynamics of pink shrimp recruitment in relation to Florida Bay salinity and temperature. Estuaries 25(6B):1335-1371.

Browder, J. A., V. R. Restrepo, J. Rice, M. B. Robblee, Z. Zein-Eldin. 1999. Environmental influences on potential recruitment of pink shrimp, Farfantepenaeus duorarum, from Florida Bay nursery grounds. Estuaries 22(2B):484-499.

Butler, M. J. Undated. Marine invertebrates: review for Everglades National Park. 5 pp.


23

Butler, M. J., D. C. Behringer Jr., J. D. Shields. In press. Transmission of Panulirus argus virus 1 (PaV1) and its effect on the s urvival of juvenile Caribbean spiny lobster. Journal of Aquatic Organisms.

Butler, M. J. IV, T. W. Dolan III, J. H. Hunt, K. A. Rose, and W. F. Herrnkind. 2005. Recruitment in degraded marine habitats: a spatially explicit, individual-based model for spiny lobster. Ecological Applications 19:902-918.

Butler, M. J., IV. 2003. Incorporating ecological process and environmental change into spiny lobster population models using a spatially-explicit, individual-based approach. Fisheries Research 65:63-79.

Criales, M. M., J. A. Browder, M. B. Robblee, T. Jackson, and H. Cardenas. 2008. Concentration and upstream migration of pink shrimp postlarvae in northwestern Florida Bay. Abstract. 2008 Florida Bay Conference.

Criales, M. M., J. A. Browder, C. Mooers, M. B. Robblee, and T. L. Jackson. 2007. Cross-shelf transport of pink shrimp larvae: interactions of tidal currents, larval vertical migrations, and internal tides. Marine Ecology Progress Series 345:167-184.

Criales, M. M., J. Wang, J. A. Browder, M. B. Robblee, T. L. Jackson, and C. Hittle. 2006. Cross-shelf transport of pink shrimp postlarvae into Florida Bay via the Florida shelf. Fishery Bulletin 104:60-74.

Criales, M. M., J. Wang, J. A. Browder, and M. B. Robblee. 2005. Tidal and seasonal effects on transport of pink shrimp postlarvae. Marine Ecology Progress Series 286:231-238.

Jones, D. L., M. B. Lara, Z. Chen, J. T. Lamkin, and E. Malca. Submitted. Taxonomic and spatial variation of otolith microchemistry among three species of juvenile snapper from southern Florida. NOAA National Marine Fisheries Service and UM CIMAS.

Lara, M. R., D. L. Jones, Z. Chen, J. T. Lamkin, C. M. Jones. In prep. Spatial variation of otolith elemental signatures among juvenile gray snapper (Lutjanus griseus) inhabiting southern Florida waters. NOAA National Marine Fisheries Service and UM CIMAS.

Lorenz, J. J. and J. E. Serafy. 2006. Subtropical wetland fish assemblages and changing salinity regimes: implications for everglades restoration. Hydrobiologia 569:401-421.

Powell, A. B. 2008. Spotted seatrout monitoring in Florida Bay. Year-3 Annual report to RECOVER and the U.S. Army Corps of Engineers. NOAA National Marine Fisheries Service, Southeast Fisheries Science Center, Beaufort, NC Laboratory. 32 pp.

Powell, A. B. 2003. Larval abundance, distribution, and spawning habits of spotted seatrout (Cynoscion nebulosus) in Florida Bay, Everglades National Park, Florida. Fishery Bulletin 101:704-711.

Robblee, M. B. and J. A. Browder. 2008. Year-3 Annual report of the South Florida Fish and Invertebrate Assessment Network for MAP activities 3.2.3.5 and 3.2.4.5.to RECOVER and the U.S. Army Corps of Engineers. U.S. Geological Survey Center for Water and Restoration Studies and NOAA National Marine Fisheries Service. 271 pp.

Schofield, P. J. 2003a. Habitat selection of two gobies (Microgobius gulosus, Gobiosoma robustum): influence of structural complexity, competitive interactions, and presence of a predator. Journal of Experimental Marine Biology and Ecology.

Schofield, P. J. 2003b. Salinity tolerance of two gobies (Microgobius gulosus, Gobiosoma robustum) from Florida Bay. Gulf of Mexico Science 2003:86-91.

Schofield, P. J. 2005. Predation vulnerability of two gobies (Microgobius gulosus; Gobiosoma robustum) is not related to presence of seagrass. Florida Scientist 68:25-34.

Schofield, P. J. 2004. Influence of salinity, competition and food supply on the growth of Gobiosoma robustum and Microgobius gulosus from Florida Bay, U.S.A. Journal of Fish Biology 64:82-832.

Silverman, N. 2006. Hurricane-induced conversion of mangrove forest to mudflat: impacts on nekton, Big Sable Cree, Florida, USA. MS Thesis, University of South Florida College of Marine Science. 44 pp.

Silverman, N. L, C. C. McIvor, J. M. Krebs, and V. A. Levesque. 2006. Hurricane-induced conversion of mangrove forest to mudflat: impacts on nekton, Big Sable Creek, Florida, USA. Bulletin of Marine Science 80(3):933. Abstract, 2006 Greater Everglades Ecosystem Restoration Conference.

Tellier, M. S. and R. Bertelsen. 2008. Monitoring the Flora and fauna of the nearshore hardbottom habitats of the Florida Keys. Final report to the Florida Fish and Wildlife Research Institute for Florida’s Wildlife Legacy Initiative, Florida’s State Wildlife Grants Program. FWRI File Code: P2196-05-08-P. 81 pp.


24

Wright, A., T. Gerard, E. Malca, and J. Lamkin. 2008. The use of otolith microchemistry to determine sources of Lutjanid recruits to the Dry Tortugas Ecological Reserve. Abstract. Florida Bay Conference. 1 pp.

Volety, A. M. Savarese, B. Hoye, and A. N. Loh. 2008. Landscape pattern: present and past distribution of oysters in South Florida Coastal Complex. September 29 Progress report to RECOVER and the South Florida Water Management District. Florida Gulf Coast University, Ft. Myers, FL. 17 pp.

Zito, A. N. and M. J. Childress. 2007. Testing the Allee effect recruitment hypothesis in the Caribbean spiny lobster. Manuscript for submission to New Zealand Journal of Marine and Freshwater Research. Clemson University Department of Biological Sciences, Clemson, SC. 37 pp.

Contact Information: Joan A. Browder, NOAA Fisheries, 75 Virginia Beach Drive, Miami, FL 33149, Phone: 305-361-4270, Email: [email protected]


25

Connectivity Between the Mangrove Ecotone Region and Florida Bay: Current Understanding in Carbon and Nutrient Fluxes Victor H. Rivera-Monroy1, Stephen E. Davis III2, Robert R. Twilley1, Daniel L. Childers3, Rudolf Jaffe3, Randolph Chambers4, David Rudnick5, Edward Castañeda-Moya1,Tiffany Troxler1,3, Carlos Coronado-Molina5,Gregory B. Noe6, Fred Sklar5, Ehab Meselhe7 and Beatrice Michot7

1Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA 2 Department of Wildlife & Fisheries Sciences, Texas A&M University, College Station, TX 3Southeast Environmental Research Center, Florida International University, Miami , FL 4Biology Department, College of William & Mary, Williamsburg , VA 5Everglades Division, South Florida Water Management DistrictWest Palm Beach, FL 6U.S. Geological Survey, Reston, VA 7 Center for Louisiana Inland Water Studies and Department of Civil Engineering, University of Louisiana-

Lafayette, Lafayette LA Carbon and nutrient fluxes between the mangrove ecotone and Florida Bay are strongly modulated by hydrology and hydrodynamic processes, which will be significantly modified by undergoing ecosystem restoration plans. The mangrove ecotone is a functional estuarine landscape unit that conveys freshwater flows and regulates nutrient exchange with Florida Bay and the Gulf of Mexico (Figure 1). Reduced freshwater delivery over the past 50 years combined with Everglades compartmentalization and a 10 cm rise in coastal sea level has led to the landward transgression (~1.5 km in 54 years) of the mangrove ecotone. The structural changes associated with this transgression are hypothesized to have altered the fluxes of nutrients (especially nitrogen) to Florida Bay. Previous studies have shown variation in nitrogen (N) flux within dwarf and fringe mangrove areas of Taylor River (i.e., lower Taylor Slough) and Shark River (lower Shark River Slough), while other studies have quantified N fluxes through this mangrove ecotone utilizing a hydrologic modeling approach. Recent studies using Shuttle Radar Topography Mission elevation data show that approximately 49 % of the total area of mangrove wetlands in the mangrove ecotone is covered by tree canopies with tree heights < 3m, mainly in the southeastern region along Taylor Slough. Low stature scrub mangroves are widely distributed in the southeastern Everglades region (Figure 1). Scrub mangroves are apparently the result of a combination of low soil phosphorus (<59 µg P g dw-1) in the calcareous marl substrate, particularly low inorganic P concentrations and a long hydro-period. In contrast to other subtropical and tropical costal ecosystems where the estuarine region is N-limited and the upstream freshwater areas are P-limited, the estuarine mangrove ecotone landscape and its freshwater watersheds are limited by P due to the lack of terrigenous sediment input. Thus, the primary source of P to this wetland ecosystem is the Gulf of Mexico instead of the upland watershed. This P supply from the Gulf is provided in pulses by tropical storms and hurricanes, which can deposit up to 6-63% of the TP already stored in the soil (735 µg g dw-1) in a single event--supporting high mangrove net primary productivity (1100 g C m-2 yr-1). As result of spatially variable storm deposition of P the mangrove forest show a strong productivity gradient from the western south Florida n coastline (e.g., Shark River) to Taylor River slough and Florida Bay. Standing biomass ranges from 20-130 Mg h-1 across the mangrove ecotone region (Figure 2). These values are first-rate estimates based on allometric relationships developed using field information of areas subjected to a wide range of natural disturbances (lighting, hurricanes) (Figure 3). Current estimates of annual N (0.46 g N m-2) and P (0.007 g P m-2) export from the mangrove ecotone (Taylor Slough) to adjacent coastal waters indicates the regulatory effect of land and water use upstream, which can drive major alterations in productivity and spatial distribution of wetland vegetation in the mangrove ecotone zone. Seasonal variation in


26

freshwater input strongly controls the temporal variation of N and P exports (99%) to Florida Bay. Rapid changes in nutrient availability and vegetation distribution during the last 50 years show that future land use decisions might exert, on the short term, a major influence at a scale similar to sea level rise, in regulating nutrient cycling and wetland productivity in the mangrove ecotone region.

Figure 1. Map of mangrove tree height for the Everglades National Park (from Simard et al 2006).


27

Figure 2. Map of standing biomass distribution (Mg/ha) contained in mangroves of the Eveglades National Park, south Florida. This map was computed using the mean tree height derived from SRTM elevation data (i.e.,SRTM-E) and a linear regression of biomass versus mean height (see Figure 3).


28

Figure 3. Biomass versus mean tree height as measured on the field and using allometric equations of Smith et al (2007). Contact Information: Victor H. Rivera-Monroy, Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA 70803 USA, Phone: 225-578-2745; Fax: 225-578-6423, Email: [email protected]


29

Florida Bay Biogeochemistry and Phytoplankton Dynamics: Synthesis for Ecosystem Management and Restoration David Rudnick1, Joseph Boyer2, Stephen Blair3, Patricia Glibert4, Cynthia Heil5, Rudolf Jaffé2, René Price2, Marguerite Koch6 and Christopher Madden1

1Everglades Division, Watershed Management Department, South Florida Water Management District, West Palm Beach, FL

2Southeast Environmental Research Center, Florida International University, Miami, FL 3Ecosystem Restoration & Planning Division, Miami-Dade County Department of Environmental Resources

Management, Miami, FL 4University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge MD 5Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL 6Biological Sciences Department, Florida Atlantic University, Boca Raton, FL

Understanding how Florida Bay’s ecological structure and function are affected by human activities is essential for improving management of this ecosystem, especially with regard to the large-scale restoration of the greater Everglades ecosystem. The primary functional link between the Everglades watershed and Florida Bay is the flow of fresh water, which also delivers dissolved and particulate materials to the bay. This hydrologic linkage is a focus of both ongoing efforts to improve water management operations and ecosystem restoration within the Comprehensive Everglades Restoration Plan (CERP) – improved flows and resultant salinity regimes are expected to improve the estuarine ecosystem. However, increasing or redistributing fresh water flow to Florida Bay may also change nutrient inputs, biogeochemical cycling within the bay, and water quality characteristics. To achieve management goals, especially with regard to the protection and restoration of seagrass habitat and associated fauna, it is important that phytoplankton blooms are not increased and that light availability to sustain seagrass is not decreased. Documenting the status and trends of Florida Bay water quality and increasing our understanding the functional relationship between the Everglades and the bay is essential if we are to understand and predict the effects of environmental management actions. For this purpose, coastal water quality (including chlorophyll a as an indicator of phytoplankton biomass) has been monitored since 1991 and extensive research and modeling have been undertaken since the mid 1990s. Major findings were synthesized by Boyer et al. and Hitchcock et al. in a technical report prepared for the 2005 Florida Bay and Adjacent Marine Systems Science Conference (Hunt and Nuttle, 2007). Since that time, monitoring has continued and research has focused on increasing our understanding of phytoplankton bloom dynamics. A major component of this research has been to quantify the importance of dissolved organic matter (DOM) derived from the Everglades and the bay (especially seagrass) as a nutrient sources for phytoplankton. Concurrently, modeling has proceeded with the development of a large-scale water quality model and simpler models to evaluate specific water quality questions. Several workshops and synthesis reports have been completed over the past few years, providing results and insights regarding Florida Bay water quality. They include the South Florida Water Management District’s annual South Florida Environmental Reports (e.g. Rudnick et al. 2008), RECOVER’s 2007 System Status Report on the Southern Estuaries Module, led by C. Kelble, J. Boyer, and J. Serafy (RECOVER 2007), a RECOVER workshop on dissolved organic matter fate and effects in Florida Bay (Jaffe and Boyer 2008), and an interagency workshop on Florida Bay algal blooms (Donahue and Diersing 2008). A status report on findings of the Florida Coastal Everglades – Long Term Ecological Research Program, with several papers regarding Florida Bay biogeochemistry, was published in a special issue of Hydrobiologia (Trexler et al.


30

2006). Finally, a regional estuarine water quality indicator, based on chlorophyll a, has been developed for the South Florida Ecosystem Restoration Task Force (Boyer et al. 2008). Here, we present a summary of key findings from these recent efforts, with a focus on recent nutrient changes and phytoplankton blooms in eastern Florida Bay. Monitoring in Florida Bay has documented long-term water quality changes. After the extensive phytoplankton booms of the early and mid-1990s, chlorophyll a, and nutrient concentrations (total N and P, organic C, dissolved inorganic N) and turbidity decreased for nearly a decade. This trend was interrupted by a sharp increase in most of these water quality parameters, including chlorophyll a, in the months following Hurricane Irene in 1999, but concentrations then returned to relatively low levels through 2004. However, with the onslaught of three hurricanes in the fall of 2005, phytoplankton blooms and associated nutrient concentrations increased in much of the bay. This change was most pronounced at the eastern boundary of Florida Bay, where phytoplankton blooms previously had not been observed (except for about six months following Hurricane Irene) and the long-term mean chlorophyll a concentration (1992-2005) was low, 0.5 μg/L (Figure 1). Extensive monitoring and research of this eastern phytoplankton bloom has provided insights regarding the relationships among bloom dynamics, nutrient biogeochemistry, and ecosystem structure.

Barnes Sound CHL a

012345678

D-9

0

D-9

1

D-9

2

D-9

3

D-9

4

D-9

5

D-9

6

D-9

7

D-9

8

D-9

9

D-0

0

D-0

1

D-0

2

D-0

3

D-0

4

D-0

5

D-0

6

D-0

7

D-0

8

CH

L a

(ug/

l)

Barnes Sound TP

0.00.51.01.52.02.53.03.5

D-9

0

D-9

1

D-9

2

D-9

3

D-9

4

D-9

5

D-9

6

D-9

7

D-9

8

D-9

9

D-0

0

D-0

1

D-0

2

D-0

3

D-0

4

D-0

5

D-0

6

D-0

7

D-0

8

TP (u

M)

Barnes Sound TOC

0200400600800

100012001400

D-9

0D

-91

D-9

2D

-93

D-9

4D

-95

D-9

6D

-97

D-9

8D

-99

D-0

0D

-01

D-0

2D

-03

D-0

4D

-05

D-0

6D

-07

D-0

8

TOC

(uM

)

Blackwater Sound TP

0.00.5

1.01.5

2.02.5

3.03.5

D-9

0

D-9

1

D-9

2

D-9

3

D-9

4

D-9

5

D-9

6

D-9

7

D-9

8

D-9

9

D-0

0

D-0

1

D-0

2

D-0

3

D-0

4

D-0

5

D-0

6

D-0

7

D-0

8

TP (u

M)

Blackwater Sound CHL a

012345678

D-9

0

D-9

1

D-9

2

D-9

3

D-9

4

D-9

5

D-9

6

D-9

7

D-9

8

D-9

9

D-0

0

D-0

1

D-0

2

D-0

3

D-0

4

D-0

5

D-0

6

D-0

7

D-0

8

CH

L a

(ug/

l)

Blackwater Sound TOC

0200400600

800100012001400

D-9

0

D-9

1

D-9

2

D-9

3

D-9

4

D-9

5

D-9

6

D-9

7

D-9

8

D-9

9

D-0

0

D-0

1

D-0

2

D-0

3

D-0

4

D-0

5

D-0

6

D-0

7

D-0

8

TOC

(uM

)

Figure 12-FB6. Monthly chlorophyll a, TP, and total organic carbon (TOC) concentrations at SFWMD/FIU monitoring sites in Barnes Sound and Blackwater Sound since March 1991. The sharp TP peak, associated with algal bloom initiation, occurred in October 2005.


31

The eastern phytoplankton bloom was first observed as a regional phenomenon, from Duck Key in eastern Florida Bay to Card Sound in southern Biscayne Bay, in November 2005, following the Hurricanes Katrina, Rita, and Wilma in August, September, and October. Unlike the short-term (3 to 6 month) response to Hurricane Irene, the 2005 bloom event persisted for more than two years (Figure 1). Highest chlorophyll a concentrations, above 20 μg/L, were most common in Blackwater Sound, Barnes Sound, and Lake Surprise, and the bloom appeared to be spatially centered near U.S. Highway 1. As in typical central Florida Bay blooms, the eastern bloom was largely composed of a suite of cyanobacteria, dominated by Synechococcus spp. Initiation of the eastern bloom appears to have been related to two major sources of ecosystem disturbance: the 2005 hurricanes and the widening of U.S. Highway 1 from Key Largo to the mainland. This widening, which included the clear-cutting and mulching of adjacent mangroves and mixing of the peat soil to bedrock with mangrove mulch and concrete to stabilize the road bed, began in April 2005 and proceeded adjacent to Florida Bay for more than one year. Hurricane disturbances included many factors: a large discharge of fresh water and phosphorus from the C-111 canal; abrupt salinity change and with this discharge, wetland runoff, and local rainfall; potential water column stratification caused by rainfall and runoff, with resultant hypoxia or anoxia; and the impact of high winds, waves, storm surge on plants, soils, sediments, and ground water in the region. The proximity of the bloom to both sides of U.S. Highway 1 suggests that the unique disturbance of road construction was involved as a cause of the bloom, while the timing of the bloom suggests the importance of hurricane disturbance as a cause. Interactions between these factors was also likely, with hurricane wind and waves exporting materials (organic carbon and nutrients) mobilized by road construction. The proximate trigger of this regional phytoplankton bloom appears to have been a regional increase in P availability, as evidenced by the finding of extraordinarily high TP concentrations (1μM to 3 μM) in FIU/SFWMD water quality monitoring samples in early October 2005 (Figure 1). This corresponded to roughly 19 metric tons more TP than is typically found in the water column (Rudnick et al. 2008). Much of this P likely originated from the C-111 Canal (about 3 MT) and U.S. 1 soils and mulch, but the broad geographic distribution of elevated TP concentrations and absence of clear concentration gradients from the canal, indicates the importance of additional sources affected by Hurricanes Katrina and Rita. The largest P pools reside in ground water, sediments, and benthic vegetation and hurricanes may have triggered a P release from benthic sources (especially from iron minerals) via water column stratification, followed by benthic hypoxia or anoxia. About two weeks after Hurricane Katrina, Miami-Dade DERM measured very low dissolved oxygen (< 1 mg/L) during daytime in basins adjacent to U.S. 1, as well as in Little Madeira Bay. Organic carbon derived from U.S. 1 disturbance may have increased DO demand in basins near the road. Evidence supporting this hypothesis is that elevated TOC concentrations were measured throughout the region through most of 2006 and the highest concentrations (roughly double 1991-2004 baseline concentrations) were near the road (Figure1). Once initiated, the eastern phytoplankton blooms appeared to be sustained via interactive mechanisms common to blooms elsewhere in Florida Bay, including propagation of a SAV mortality feedback cycle, decreased grazing by benthic fauna (sponges), rapid nutrient cycling with P retention, and microbial (including cyanobacterial) utilization of dissolved organic nutrients derived from internal (especially SAV) and terrestrial sources. Prolonged blooms are also a consequence of the long residence times of waters in Florida Bay’s central and eastern


32

basins. Extensive mortality of Thalassia testudinum and green algae, particularly deep portions of Blackwater Sound and Barnes Sound, occurred following the 2005 hurricanes and cyanobacterial bloom initiation. This likely provided N and P to sustain the blooms, yielding prolonged low light for SAV and further mortality. Furthermore, a mass-mortality of sponges occurred in Blackwater Sound, Barnes Sound, and Manatee Bay between July and October 2005, decreasing grazing pressure on phytoplankton. [Note that this sponge mortality occurred prior to regional bloom initiation, but may have been caused by local cyanobacterial blooms following Hurricane Katrina in August, anoxia or hypoxia in these basins, or stress from rapid salinity change.] Bioassays with bloom assemblages demonstrated nutrient limitations, including nitrogen limitation after bloom initiation, rapid growth when enriched with dissolved organic nutrients (particularly organic N), and the ability to internally store P. These findings indicate that after nutrients are mobilized from internal sources (e.g. SAV, which releases labile dissolved organic nitrogen and phosphorus) or transported from external sources (which are primarily in the form of dissolved organic matter), microorganisms can rapidly cycle and retain limiting nutrients within the water column. Biogeochemical cycling of nutrients was also likely altered by the introduction of organic matter from the road construction disturbance. Another notable phytoplankton bloom occurred during the summer of 2007 in the southern portion of the bay, centered between Twin Key Basin and Islamorada. The cause of this bloom is uncertain, but it was accompanied by a large scale, mass mortality of sponges, virtually eliminating 22 of 24 sponge species in the area (Butler et al. in Donahue and Diersing 2008). Similar sponge mortality was observed associated with the early 1990s blooms and subsequent research demonstrated the potential importance of grazing as a mechanism that can prevent or minimize phytoplankton blooms. These examples highlight the importance of understanding internal biogeochemical and biotic processes in order to understand Florida Bay phytoplankton bloom dynamics. While external nutrient loading remains an important concern, particularly with regard to future Everglades restoration efforts, the low flushing and long water residence time of eastern and central Florida Bay amplifies the importance of internal nutrient cycling and biotic interactions. Benthic nutrient fluxes from surface sediments and potentially from ground water exchange greatly exceed watershed inputs. Seagrass community dynamics, including below-ground “mining” of sedimentary P stores and incorporation into SAV biomass, rapid cycling of organic P from this tissue, and the sensitivity of seagrass communities to disturbance, appear to be key determinants of whether the bay ecosystem tips toward benthic or pelagic dominance. References: Boyer, J.N., C.R. Kelble, P.B. Ortner, and D.T. Rudnick. 2009. Phytoplankton bloom status: an indicator of water

quality condition in the southern estuaries of Florida, USA. Submitted to Ecological Indicators. Donahue, S. and N. Diersing. 2008. Synopsis, Algae Bloom Workshop. Florida Keys National Marine Sanctuary.

33pp. Hunt, J. and W. Nuttle (eds). 2007. Florida Bay Science Program: A Synthesis of Research on Florida Bay. FWRI

Technical Report TR11. Florida Fish and Wildlife Conservation Commission. 148 pp. Jaffé, R. and J. Boyer. 2008. Workshop Final Report. SFWMD. 16 pp. RECOVER 2007. System Status Report, Section 7, Southern Estuaries Module. 95 pp. [http://www.evergladesplan.org/pm/recover/recover_docs/at_ssr_2007/2007_ssr_final_sect_7_southern_est.pdf ] Rudnick, D., C. Madden, R. Bennett, A. McDonald, S. Kelly, K. Cunniff, R. Alleman, R. Chamberlain, P. Doering,

M. Gostel, D. Haunert, M. Hedgepeth, M. Hunt, B. Orlando, C. Qiu, and P. Walker. Management and Restoration of Coastal Ecosystems. Chapter 12, 2008 South Florida Environmental Report. SFWMD. 110 p.


33

[https://my.sfwmd.gov/pls/portal/docs/PAGE/PG_GRP_SFWMD_SFER/PORTLET_SFER/TAB2236041/VOLUME1/chapters/v1_ch_12.pdf]

Trexler, J., E. Gaiser, and D. Childers. 2006. Interactions of hydrology and nutrients in controlling ecosystem function in oligotrophic environments of South Florida. Hydrobiologia 569:1-2.

Contact Information: David T. Rudnick, Everglades Division, Watershed Management Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL, 33401, USA Phone: 561-753-2400 x4646, Fax: 561-791-4077, Email: [email protected]


34

Figure 1: Everglades National Park Marine Monitoring Network

Physical Processes: What Have We Learned about Florida Bay in the Past Five Years, and How Is That Useful to CERP Planning and SFER Management? Peter Ortner

NOAA/AOML, Miami, FL After the 2001 Florida Bay Science Conference a group of investigators within the Florida Bay Science Program were asked to provide a synthesis of their research results with regard to what was then called Question 1: How and at what rates do storms, changing freshwater flows, sea level rise, and local evaporation/precipitation patterns influence circulation and salinity patterns within Florida Bay and exchanges between the bay and adjacent waters? That synthesis was updated to reflect subsequent research over the next two years and then disseminated on line. Eventually this physical processes synthesis constituted one chapter in a technical report providing an overall synthesis and integration of the Science Program (Hunt and Nuttle, eds., 2007). Regarding these same issues, the question posed herein is: What have we learned since 2003, and how is that useful to CERP planning and SFER management? The answer is provided by, among other sources, the abstracts and poster contributions to the present 2008 Science Conference that relate specifically to Florida Bay. It is divided herein into two distinct but fully interdependent sub-sections (Modeling and Observations). Modeling:

In 2003 linear regression methods were just beginning to be used to relate upstream flow and stage to downstream (Florida Bay) salinity. Since then multivariate linear regression (MLR) salinity models have been developed for all of the 33 ENP Marine Monitoring Network stations in Florida Bay , on the Gulf coast, and Barnes Sound/Manatee Bay (Fig. 1) as a function of stage in the Everglades, wind, and sea surface elevation at Key West (see Marshall et al. presentation). These models have been coded by the Interagency Modeling Center and are being used for CERP alternative reviews, Interim Operating Plan analysis and performance measure evaluations by the Southern Estuaries Sub-team of RECOVER . These and other linear statistical models have been used to create historical reconstructions of paleo-salinity in Florida Bay that favorably compare with paleo-salinity regimes derived from USGS core interpretations, and have also been successfully coupled with pink shrimp growth models.

In 2003 we also called for the development of verified calibrated numerical circulation models on nested scales connecting the Bay interior to adjacent waters and to the larger circulation. Progress on an interior Bay circulation model was initially rapid as an EFDC model was


35

developed under the aegis of the Florida Bay Florida Keys Feasibility Study with funding provided by the SFWMD. It has recently lagged; however, there has been considerable progress on both upstream hydrological models and larger scale circulation models. A South Florida HYCOM model was developed by Kourafalou and co-workers, the newest version of which has four times the horizontal resolution (now at ~900 m) to better represent the topography around Florida Bay and the Florida Keys. The atmospheric forcing has also been updated to a higher resolution data set, provided by the US Navy. Improved boundary conditions obtain fields of sea surface height, temperature, salinity and currents from a data assimilative Gulf of Mexico model. Detailed model evaluations have taken place, using both moored observations and in-situ surveys. An example is given in Figures 2 and 3, where an intrusion of low salinity water that was observed in the January 2005 Florida Bay survey is simulated and explained through the HYCOM model simulation. The hyper-salinity conditions that were present before the survey (January 17) are gradually alleviated through the intrusion of low salinity waters of remote origin (January 22 and 26). Simulations of at least this degree of accuracy are required to quantitatively determine the degree to which alternative upstream scenarios of water release under what circumstances may put ENP and FKNMS marine resources at risk.

Figure 2 : Near surface salinity data from the monthly Florida Bay surveys showing intrusion of low salinity waters (darker colors) from the Southwest Florida Shelf to the western Florida Bay during the dry season (January 2005).


36

In 2003 we reported upon the recent development and application of appropriate surface – and ground-water hydrological models encompassing the linkage between Florida Bay and the Everglades. A coupled hydrodynamic surface- and ground-water model code, Flow and Transport in a Linked Overland/Aquifer Density-Dependent System (FTLOADDS), has since been used in multiple applications to represent the hydrology of southern Florida, including the coastal Florida Bay area, and to evaluate potential changes to the hydrologic system caused by climatic change or restoration alternatives (see Swain et al. presentation). The application to the Everglades National Park area is referred to as to the Tides and Inflows in the Mangroves of the Everglades (TIME) application. This model incorporates salinity transport as well as improved representations of evapotranspiration and heat transport. TIME has already been used to evaluate several CERP restoration alternatives using inputs provided by the regional South Florida Water Management Model. Computed flow rates and salinity values at the coast for the different simulated CERP scenarios are used as input to the EFDC model of Florida Bay. Wetland flows, salinity values, and hydro-periods are compared between the different scenarios. The TIME model is being combined with a FTLOADDS simulation of the Biscayne Bay coastal and inland area east of L-31N and C-111. This combined simulation, referred to as the Biscayne South East Coastal Transport (BISECT) application also simulated heat transport in order to predict effects on temperature of environmental and man-made changes. Finally, in 2003 work on box models was also well underway including work with FATHOM. However, the residence times estimated thereby had not been rigorously validated or verified with observations. Since then a higher resolution variant of the model (see Cosby et al. presentation) has proven successful in simulating long-term, Bay-wide variation in salinity in response to variations in rainfall and freshwater inputs from the Everglades, and the magnitudes of transport inferred for the central and northeast regions of the Bay are consistent with independent findings by other investigators (see Observations below).

Figure 3: Near surface model-computed salinity (high resolution HYCOM model, partial domain is presented) showing low salinity waters (darker colors) advected from the Southwest Florida shelf river dominated coastal areas to western Florida Bay during the dry season (January 2005). A detail of the domain (marked with the black box) illustrates the near surface modeled currents. including the inflow to Florida Bay and the outflow to the Florida Keys.


37

Observations:

There has been a considerable body of work published describing circulation and salinity variation within Florida Bay (see also Lee et al. and Johns et al. presentations). These papers identify and describe the important physical processes driving water exchange and salinity patterns and variations. They show that local winds are the primary mechanism in providing the weak inner basin water renewal and long residence times (on the order of one year), while ground water inputs are comparatively insignificant. The cause and persistent location of hyper-salinity is shown to result from poor flushing, shallow depths and lack of fresh water input. Important guidance to CERP implementation is given by the finding that a reduction in hyper-salinity could likely be achieved by diversion of fresh water into the north central region via McCormick Creek in the dry season. As much as 75% of the direct fresh water runoff to Florida Bay discharges into the northeast sub-region, where it is mostly trapped with little impact on dilution of hyper-salinity in the adjacent north central sub-region. Therefore, diversion of a small portion of the runoff to the hyper-salinity area in the dry season would be beneficial to the Bay as a whole with little negative impact. Detailed studies of basins in the East, North Central and, most recently and reported at this conference, Western regions of the Bay essentially verify and validate many of the inferences made by the box modeling studies discussed above.

Although true adaptive event-sampling has been comparatively limited due to funding constraints over recent years, investigators from various agencies (NOAA, USGS, SFWMD, Miami-Dade DERM) have been able to document the physical (and consequent biological) effects of tropical storm passage and the water releases made in anticipation of storm landfall and rainfall inundation. There has also been a considerable advancement of our understanding of the influence of boundary currents and their eddy perturbations on coastal water properties and larval recruitment of reef and near-shore species. These results address a physical topic not considered in the physical science section of the original synthesis document but are of considerable ecological importance. They indicate that successful recruitment of numerous offshore spawning species depends upon the complex processes of eddy formation and larval retention. This has significant implications both with regard to fisheries management and protected species, and with regard to the design and implementation of marine protected areas (MPAs) within the waters adjacent to Florida Bay. Groundwater input to the Bay was highlighted as an important topic to investigate more thoroughly. In a paper to be presented at this conference (see Swarzenski et al. presentation) it is reported that 222Rn maps provide a useful gauge of relative groundwater discharge into Florida Bay. Specifically 222Rn time-series measurements provide a reasonable estimate of site specific total (saline and fresh) groundwater discharge, and the saline nature of the shallow groundwater underneath the “representative “ study site chosen indicates that most of this discharge must be recycled sea water. This conclusion is in full agreement with the above-mentioned water balance calculations based on observational studies of basins in the interior of Florida Bay. Data Access/Presentation: In the synthesis document of 2003 we highlighted efforts to develop and provide access to a database encompassing the physical oceanographic and atmospheric data required to verify and validate the models then under development or planned. As reported at this conference (see


38

Melo et al. presentation) this work is now being continued and made available through a user-friendly website. The same investigators at an earlier conference presented a high resolution animation of sea level variability over an inter-annual cycle that integrated the data from multiple agency sources. Conclusions:

To a large degree, the direction of research since 2003 has been guided by the recommendations and priorities expressed within that original synthesis. Despite severe funding constraints considerable understanding has been gained. However, since that time one physical science topic above all others rose to the forefront of popular imagination and management concern. That topic is Climate Change: specifically, the possible implications to CERP and to the management of South Florida’s ecosystems. Hence, this conference’s opening session upon that topic. From a purely physical Florida Bay perspective there seems little doubt that regardless of what we do with respect to greenhouse gas emissions, Climate Change will alter the fundamental dynamics of Florida Bay and our expectations of restoration therein. Sea level rise is projected by both models and recent observations to be both accelerating and significantly more rapidly than previously observed bank and shoreline accretion processes in Florida Bay. This suggests a future Bay that will be much better mixed, considerably larger and, at least in some places, deeper than the present Bay. If climate modelers are to be believed, freshwater inputs are likely also to differ considerably from the recent historical record, due to changes in regional precipitation patterns and tropical storm intensity. This implies both direct and indirect changes in the salinity distribution within the Bay and in the options we have available to regulate that salinity. Biblicography: Hitchcock, G. L., T. N. Lee, P. B. Ortner, S. Cummings, C. Kelble, and E. Williams, 2005. ³ Property fields in a Tortugas Eddy in the southern straits of Florida ². Deep-Sea Research Part I-Oceanographic Research Papers 52: 2195-2213. Hunt, J.H., and W. Nuttle, eds., 2007. Florida Bay Science Program: A Synthesis of Research on Florida Bay.

Fish and Wildlife Research Institute Technical Report TR-11. iv + 148 p. Kelble, W. K. Nuttle, E. Johns, T. N. Lee, C. Hittle , R. Smith, and P. B Ortner , 2006. ³ Salinity Patterns of Florida Bay ². Estuarine, Coastal and Shelf Science 71 (2007) 318-334. Kourafalou, V.H., E. Williams and T.N. Lee, 2007. Favorite drifter trajectories deployed from the western shelf of Florida and the coastal waters of the Florida Keys. In: Lagrangian Analysis and Prediction of Coastal and Ocean Dynamics, edited by A. Griffa, A. D. Kirwan, A. J. Mariano, T…zgškmen, and T. Rossby, pp. 78-82, Amazon. Kourafalou, V.H. and G. Peng, 2007. Modeling support for the Comprehensive Everglades Restoration Project (South Florida): salinity changes under natural variability and anthropogenic influence. Proceedings of the Conference on Environmental Management, Engineering, Planning and Economics, CEMEPE07, pp. 595-600. Kourafalou, V.H., R.S. Balotro, G. Peng, T.N. Lee, E. Johns, P.B. Ortner, A. Wallcraft and T. Townsend, 2006. Seasonal variability of circulation and salinity around Florida Bay and the Florida Keys: SoFLA-HYCOM results and comparison to in-situ data. UM/RSMAS Tech. Rep. 2006/04, 102 pp. Kourafalou, V.H. and R.S. Balotro, 2006. Connecting the U.S. Florida Keys coral reef ecosystem to the hydrodynamics. Proceedings of the 10th International Coral Reef Symposium: The Physical and Hydrodynamic Environments and their influence on coral reef processes, ICRS2004, 890-895. Langevin, C.D., Swain, E.D., and Wolfert, M.A. 2005. Simulation of integrated surface-water/ ground-water flow and salinity for a coastal wetland and adjacent estuary. Journal of Hydrology 314, 212-234.


39

Lee, T. N., E. Johns, N. Melo, R. H. Smith, P. Ortner and D. Smith, 2006. On Florida Bay hypersalintiy and water exchange. Bull. Mar. Sci. 79: 301-327. Lee, T. N., N. Melo, E. Johns, C. Kelble, R. H. Smith, P. Ortner, 2008. On water renewal and salinity variability in the northeast subregion of Florida Bay. Bull. Mar. Sci. 82: 83-105. Sponaugle, S., T. N. Lee, V. Kourafalou, and D. Pinkard, 2005. " Florida Current frontal eddies and the settlement of coral reef fishes ". Limnology and Oceanography, 50(4), 1033-1048. Swain, E. D., and James, D. E. 2007. Inverse Modeling of Surface-Water Discharge to Achieve Restoration Salinity Performance Measures in Florida Bay, Florida: Journal of Hydrology, Volume 351, Pages 188-202. Swain, E. D., and Wolfert, M. A., 2007, Numerical Modeling to Determine Freshwater/Saltwater Interface Configuration in a Low-Gradient Coastal Wetland Aquifer: in a New Focus on Groundwater-Seawater Interactions: IAHS Red Book Series, IUGG General Assembly, July 2007, Perugia, Italy. Wang, J. D., E. D. Swain, M. A. Wolfert, C. D. Langevin, D. E. James, and P. A. Telis. 2007. Applications of Flow and Transport in a Linked Overland/Aquifer Density Dependent System (FTLOADDS) to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida. U.S. Geological Survey Scientific Investigations Report 2007-5010. Wolfert-Lohmann, M.A., Langevin, C.D., Jones, S.A., and others, 2008, U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida: U.S. Geological Survey Open-File Report 2007-1288, 47 p.

Contact Information: Peter Ortner, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149-1098, Phone: 305-421-4619, Fax: 305-421-4221, Email: [email protected]


40


41

Abstracts

Listed alphabetically by presenting author and abstract title.

Presenting authors appear in bold.


42


43

Characterization of Natural Stream Flow in South Florida Richard Alleman

South Florida Water Management District, West Palm Beach, FL

Many of the historical rivers and streams in southern Florida have been altered by man-made impacts thus changing hydrologic characteristics over time. The most common effects are more intense and greater peak flows following storm events, and diminished flows during dry periods as a result of reduced watershed storage. Natural habitats and ecosystems in southern Florida evolved with certain hydrologic patterns that have now changed. It has been widely recognized that one of the first measures toward restoration of impacted ecosystems in south Florida is the restoration of more natural hydrologic patterns. This is particularly true for the estuaries. In most cases, southern Florida estuaries have been heavily impacted by changes in salinity patterns caused in part by changes of watershed hydrology. Most rivers and streams are highly managed for flood protection or water supply near the coast where lands have been urbanized. In addition, some of the runoff that historically passed through rivers and streams into estuaries has been diverted for other purposes or drained off through other channels. If altered surface water courses could be hydrologically restored, then it stands to reason that dependent biological systems will respond in a way that is likely to be considered positive. Before this can happen, however, managers must have some way to compare or benchmark an appropriate hydrologic pattern for a given stream. Mean daily flow records were compiled from several streams in South Florida with long periods of record. These streams, while not entirely unaffected by anthropogenic hydrologic alteration, were located in generally rural areas where impacts have not been catastrophic. The data were sorted for each stream to create flow duration curves. The majority of daily flow rate values was very similar and did not vary greatly (normal). The more intense flows at the upper end of each stream flow rate curve represented a smaller subset (peak). Just by visual inspection of one of these curves it can be discerned that the curve shapes are quite different between the normal and peak flows (Figure 1.) Since peak flows result from a variety of very wet conditions that are infrequent, and attempting to fit the entire curve would result in polynomials of many terms, just the normal flows were analyzed. In this exercise, the lowest 80 percent of flows were tested for curve fit. Several standard curves such as linear, quadratic and cubic were fitted to the data produced by the lowest 80 percent of flows from each stream. The best fits, overall, resulted from cubic equations. R2 values ranged from 0.978 to 1.000. A standardized polynomial was constructed from the equations that generalized an ideal model. An idealized flow curve can be constructed based on the mean flow for any impacted stream or even canal discharges, and compared to actual. For example, Canal C-1 located in southern Miami-Dade County discharges to Biscayne Bay. Based on the existing flow rates, a preferred flow duration curve can be compared to the existing flow duration curve. The comparison reveals that the largest discrepancy occurs at the lower flow rates where existing flows are unnaturally low about 40 percent of the time (Figure 2). The unnaturally low flows likely impact salinity patterns in Biscayne Bay that result in higher salinity compared to what would be produced by a more natural hydrologic pattern.


44

Figure 1. Example of a flow duration curve from Arbuckle Creek. In this case, the majority of the flows vary only between 0 and 500 Cubic Feet per Second (CFS). A small upper proportion varies widely up to 7,000 CFS.

Figure 2. Observed daily flow in C-1 canal near the coast of Biscayne Bay compared to a more idealized flow based on a cubic model. Contact Information: Richard Alleman, South Florida Water Management District, MSC4420, West Palm Beach, FL, 33416-4680, USA, Phone: 561-682-6716, Email: [email protected]


45

A Review of Ruppia maritima in Relation to Salinity in Northeastern Florida Bay Christian L. Avila1 and Peter Frezza2

1Miami-Dade Department of Environmental Resources Management (DERM), Miami, FL 2Audubon of Florida, Tavernier Science Center, Tavernier, FL

In the Northeastern transitional creeks and basins of Florida Bay, Ruppia maritima has been identified as a critical component of the submerged aquatic vegetation (SAV) community and as a potential indicator species for restoration and regulatory requirements for water management scenarios (i.e., Florida Bay and Florida Keys Feasibility Study (FBFKFS); development of Minimum Flows and Levels (MFL) criteria for Florida Bay). Two independent SAV monitoring programs have been documenting SAV conditions within the northeastern transitional embayments of Florida Bay. The Miami-Dade Department of Environmental Resources Management (DERM) program has been ongoing since 1993, and the Audubon of Florida program was initiated in 1996. Collectively the two programs cover many of the key areas for Ruppia in the transitional region. Relative to this review, the Audubon of Florida program surveys 3 sites: Taylor River (TR), Joe Bay (JB) and Highway Creek (HC). Each site has 6 fixed stations along a salinity gradient and sampling is conducted every six weeks. Abundance estimates of SAV are assessed using a point intercept percent coverage method. The DERM program has fixed stations and stratified random stations in Highway Creek and Joe Bay. Monitoring at fixed stations was conducted monthly for the period assessed herein, and at four week intervals for random stations up to Sept 1999, but increasing to eight week intervals after Sept 1999. Short shoots counts were taken within quadrat subdivisions at each station. Salinity data for the Audubon sites are derived from permanent, on site dataloggers used for continuous monitoring at the furthest upstream stations. At stations where permanent dataloggers are not located, regression models were created to estimate salinity using the nearest USGS or ENP hydrostation. For the DERM data evaluations, salinity from the ENP hydrostations in HC and JB was used. This review seeks to provide insight into the period of antecedent salinity that best relates to observed Ruppia coverage and discuss the spatial-temporal relationships between those antecedent conditions and the declines in Ruppia. To assess periods of decline, data sets were selected for each station wherein Ruppia had a seasonal maximum ≥20% cover or ≥35 shoots/m2 and steadily declined to ≤5% cover or ≤10 shoots/m2. To delineate the end of the ‘decline event’, once a minimum extended beyond 2 samplings the subsequent data was not included. Each Ruppia measurement within a given decline event was run in a linear regression against the mean salinity of the 30, 60, 90, 120 and 180-day period immediately prior to the day of sampling. The strongest relationships, across stations and between datasets, for Ruppia decline were found with the 90-day and 120-day antecedent mean salinity. Results for the 90-day evaluations are presented in Table 1. Of the 21 events run 16 are considered to show moderate to strong relationships (R2 >0.70). These analyses give an indication that in areas known to have lower salinity regimes, less of a change in salinity is associated with declines in Ruppia. This can be seen in the range of points where Ruppia cover/density declines to 0 (e.g., the modeled x-intercept) these points are lowest in the Taylor River, followed by Highway Creek, and lastly Joe Bay. Additionally there appears to be a relationship across the sites in the proportionality of


46

Ruppia’s tolerance to salinity between years. The minimum and maximum “0 point” values are consistent across basins. For example, the 97-98 period is the lowest and the 04-05 period is the highest for all three sites. Additional work needs to be conducted to understand this point more completely. In summary, there are indications that Ruppia populations within northeastern Florida Bay may acclimate to salinity spatially and temporally. Ruppia’s varied response to salinity must be recognized when considering this species as an indicator species in the transitional basins of the region. Table1. Linear regression results of Ruppia decline event versus 90 day antecedent salinity mean. These results include all stations meeting the ‘event decline’ criteria.

Site Dates Station Ruppia Decline N R2 F p X int.

Taylor River Jan98-Sept98 TR5 57.1% - 0.17% 6 0.573 5.4 0.081 10.8Taylor River Apr00-Nov00 TR5 85.3% - 0.5% 4 0.430 1.5 0.345 18.6Taylor River Apr02-Jul02 TR5 43.7% - 3.3% 3 0.994 174.3 0.048 20.9Taylor River Jan03-Jun03 TR4 31.5% - 3.2% 4 0.999 1855.1 <0.001 11.9Taylor River Jan04-Sept04 TR4 28.3% - 0.0% 6 0.863 25.2 0.007 26.8Taylor River Jan04-Sept04 TR1 25.5% - 0.5% 5 0.983 169.0 <0.001 25.8

Joe Bay Jan94-Sept94 JB3D 3181shts/m2 - 0.0shts/m2 9 0.779 24.705 0.002 19.7Joe Bay Nov97-Jul98 JB3 95.5% - 0.0% 6 0.332 1.992 0.231 5.6Joe Bay Nov00-Jul01 JBrand 35.0shts/m2 - 4.0shts/m2 5 0.883 22.67 0.018 30.8Joe Bay Apr01-Sept01 JB3 37.5% - 2.7% 4 0.197 0.491 0.556 40.8Joe Bay Mar02-Jun02 JB5 25.0% - 0.7% 3 0.985 66.791 0.078 27.4Joe Bay Jan04-Sept04 JBrand 45.0shts/m2 - 0.0shts/m2 5 0.765 9.765 0.052 34.4Joe Bay Dec04-Jun05 JB2 21.5% - 0.0% 5 0.874 20.84 0.020 35.4Joe Bay Oct06-Jun07 JB2 24.7% - 1.5% 6 0.809 16.96 0.015 22.7

Highway Creek Mar96-Jun96 HCrand 290shts/m2 - 0.0shts/m2 4 0.766 6.53 0.125 23.1Highway Creek Nov97-Aug98 HCrand 138shts/m2 - 7shts/m2 10 0.731 21.786 0.002 15.6Highway Creek Apr98-Sept98 HC5 25.4% - 1.0% 4 0.996 483.764 0.002 15.8Highway Creek Jan02-Jun02 HC5 20.3% - 0.5% 4 0.952 39.897 0.024 27.6Highway Creek Sept02-May03 HCrand 50shts/m2 - 0.0shts/m2 5 0.731 8.155 0.065 17.6Highway Creek Dec04-Jul05 HC3 23.3% - 1.7% 6 0.762 12.782 0.023 39.3Highway Creek Apr07-Dec07* HC1A 31.0% - 1.2% 6 0.534 4.581 0.099 3.1

*Postive relationship. Contact Information: Christian Avila, Miami-Dade Department of Environmental Resources Management, 701 NW 1st Court, Miami, FL, 33136, USA, Phone: 305-372-6861, Email: [email protected]


47

Seagrass Communities of Biscayne Bay, 1999-2007 Miami-Dade County Christian L. Avila, Stephen Blair, Sheri Kempinski, Santiago Acevedo and Jonathan Sidner

Ecosystem Restoration & Planning Division, Miami-Dade County Department of Environmental Resources Management. Miami, FL

Miami-Dade County DERM, in partnership with the South Florida Water Management District (SFWMD), has maintained a benthic habitat monitoring program in Biscayne Bay since 1985. Initially, assessments were based on ten fixed-transect stations positioned at strategic locations between Haulover Inlet and Black Point. Three 1-m2 grids were assessed at three fixed points along a 50 meter at each station. Short shoots of each seagrass were counted in five haphazardly selected, 0.2 m2 subgrids of each 1 m2 grid (e.g., 15 counts [0.6m2] per station). Sampling periodicity has varied, but no less frequently than annually in June. In 1999, the SAV assessment was expanded to include all southern portions of the Bay (Rickenbacker basin and south to Card Sound). The Braun-Blanquet Cover Abundance (BBCA) rapid visual assessment method (Forqueran et al., 2002) was employed. A total of 101 area-equal sampling regions were identified. The size and shape boarding polygons were modified to affect a shoreline ‘buffer zone’ of 100m. Up to 18 potential sampling regions were identified in each polygon (actual number ranged between 9 and 18 due to size of ‘boarder’ polygons). Station assessment entailed BBCA assessment of each seagrass species present in four haphazardly placed 0.25m 2 grids. For the purposes of this evaluation, shoot density data from the fixed transects was used to describe SAV populations in northern Biscayne Bay, while the more spatially complete BBCA data was used for the central and southern Biscayne Bay region. Comparative assessment between ‘fixed transect’ and ‘BBCA’ assessments of SAV in south Biscayne Bay were also conducted. The mean and standard deviation in the annual BBCA scores were calculated and plotted for each three year periods as well as the 9 year period of consideration (Figure 1) to determine the variation in the spatial distribution and density of the three major SAV components: Thalassia testudinum, Syringodium filiforme, and Halodule wrightii. North Biscayne Bay (e.g., from Haulover Inlet to Rickenbacker Causeway) is boarded by a highly developed and urbanized shoreline and highly modified bay bottom associated with coastal navigation and development. The data from fixed transects in this region show Syringodium to be the dominant seagrass, with Thalassia present in low densities, and variable Halodule densities. For example, between 1997-1999 two stations; Haulover Inlet (BB06) and 79th St. Causeway (BB10), experienced a complete loss of seagrass. BB06 was likely influenced by periodic maintenance dredging of the Intercoastal Waterway proximal to the station; however no specific causative factors have been identified for the losses at BB10. Both stations currently appear to be undergoing a recovery of seagrass, with Syringodium and Halodule returning to BB06 in 2005, and in 2007 to BB10. In South Biscayne Bay (Rickenbacker basin and south to Card Sound) the mean BBCA values for the 9 year evaluation period and standard deviations (SD) indicate that Thalassia is the dominant seagrass (BBCA cover/abundance score of Thalassia ranges mainly 1 to 5 [e.g., estimated 5% to 100% cover]), with highest cover in the northwestern and central-eastern portions of the bay. Halodule is common though not as abundant within this region, with a highest coverage occurring in the northern, western and extreme southern sections. The BBCA scores were commonly 1 or less (e.g., estimated ≤5% cover), with a maximum of 3 (estimated 25 to 50% cover) in one polygon in the extreme south of the area. Syringodium has the most restricted


48

distribution in this area being found most commonly in the northern and southern most portions of this region, with a range of BBCA scores and cover equivalent to that of Halodule. Ruppia maritima was not identified within the study region (e.g., >100 m from shoreline). Evaluation of a series of 3-year mean BBCA score, and the 9-year mean and SD, indicate stable seagrass populations in large regions of the Rickenbacker-to-Card Sound potion of Biscayne Bay. The regions of greatest variability occur in the hardgrounds regions of the bay.

Figure 1. Nine-yean mean and Standard Deviations of BBCA Scores for Thalassia, Halodue and Syringodium in Biscayne Bay. Contact Information: Christian Avila, Ecosystem Restoration & Planning Division, Miami-Dade Department of Environmental Resources Management, 701 NW 1st Ct., Miami, FL, 33160, USA, Phone: 305-372-6861, Fax: 305-372-6659, Email: [email protected]


49

Effects of Groundwater on Salinity in Biscayne Bay Sarah Bellmund1, Greg Graves2, Steve Krupa2, Herve Jobert3, Greg Garis1 and Steve Blair4

1Biscayne National Park Salinity Monitoring Program, Biscayne National Park, Homestead, FL 2South Florida Water Management District, West Palm Beach, FL 3Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL 4Miami-Dade County Department of Resources Management, Miami, FL

Biscayne National Park manages an extensive salinity monitoring program in Biscayne Bay. This program is a portion of the Comprehensive Everglades Restoration Plan (CERP) Monitoring and Assessment Plan (MAP) to provide information necessary to assess the effects of the CERP program on Biscayne Bay. Historically Biscayne Bay received extensive freshwater flow as both overland and through groundwater flow. This flow has been dramatically affected by the reduction of freshwater due to development of south Florida beginning in the 1890s. Lowering groundwater for development, the construction of the central and south Florida system as well as the construction and operation of the south Dade Conveyance System have diverted or severely modified freshwater flow to Biscayne Bay. The salinity monitoring system in place in Biscayne Bay consists of 34 monitoring sites instrumented with YSI 6600 data sondes that continuously record conductivity, temperature, and depth. These instruments record every fifteen minutes and most have been in place since summer 2004. This data has allowed us to identify sites we believe are affected by groundwater flow. This data combined with seepage meter data collected in Bay is some of the most compelling evidence of the current importance of groundwater to the coastal areas of Biscayne Bay. Data supporting this includes several sites which exhibit the phenomena of “fresher on the bottom”. Seepage meter data supports this observation as does observation and measurement of fresh or lower salinity water flowing from seeps into the Bay. This data is proving extremely useful to understanding the controlling water flow features affecting the Bay. Contact Information: Sarah Bellmund, Salinity Monitoring Program, Biscayne National Park. 9700 S.W. 328th St., Homestead, FL 33033, Phone: (305) 230-1144, Email: [email protected]


50

Monitoring Coral Bleaching as an Indicator of Climate Change Resilience for Florida’s Reefs Chris Bergh

The Nature Conservancy, Summerland Key, FL, USA The Florida Reef Resilience Program (FRRP) is a collaborative effort among managers, scientists, conservation organizations and reef users to develop resilience-based management strategies for coping with climate change and other stresses on Florida’s coral reefs. With projected increases in coral bleaching due to climate change, the FRRP Disturbance Response Monitoring (DRM) was developed for monitoring shallow coral reefs from Martin County to the Dry Tortugas. The DRM consists of a probabilistic sampling design and a stony coral condition monitoring protocol implemented across 59 discrete reef zones during the annual period of peak thermal stress. Surveys were implemented during the summers of 2005-2007 by 12 teams from federal, state, and local government agencies, non-profit organizations, and universities coordinated by The Nature Conservancy. Each year, survey teams cooperated to complete approximately 160 surveys across the south Florida reef tract within a six week period. Two independent 1x10m belt transects were randomly placed within each 200x200m sampling site. Information was gathered on the coral population’s size-frequency, size structure, and bleaching prevalence. In 2005, bleaching and paling, a precursor to bleaching, was moderate overall with 21% to 50% of coral colonies paling or bleached. In 2006, bleaching and paling was mild overall with less than 20% of coral colonies paling or bleached in all but one reef zone. In 2007, bleaching and paling was intermediate in prevalence between 2005 and 2006 with a majority of zones experiencing mild paling and bleaching, seven zones moderate and one zone exhibiting severe bleaching. DRM results show spatial and temporal patterns in coral bleaching and colony size frequency distribution, indicating that some zones and coral species may be more resilient to stress than others. While the exact causes of the variability between zones and coral species are not certain, the underlying predictability of this variability itself may provide new tools for managers to cope with climate change. Contact Information: Chris Bergh, The Nature Conservancy, P.O. Box 420237, Summerland Key, FL, 33042, USA, Phone: (305) 745-8402, Fax: (305) 745-8399, Email: [email protected]


51

Effects of Light and Nutrient Supply on Stable Isotope Composition and Fractionation in N-Limited Seagrass Beds Rebecca J Bernard1 and James W Fourqurean2

1Florida International University, Department of Biological Sciences, Miami, FL, USA 2Florida International University, Department of Biological Sciences and SERC, Miami, FL, USA

INTRODUCTION Seagrasses are a critical component of the nearshore marine environment and can be described as the “canary” of the marine ecosystem because they are sensitive to both nutrient and light alteration due to anthropogenic and climate perturbations. Seagrasses are sensitive to increased nutrient loads that reduce light available for benthic plant primary production. Therefore, understanding the relationship between seagrasses and coastal eutrophication due to increased anthropogenic nutrient loading is necessary not only in the promotion of the progress of science, but also in the development of effective coastal management strategies and restorative measures to improve nearshore marine ecosystem health in the expanse of global climate change. Stable isotopes of nitrogen are a useful tool to elucidate the relationship between anthropogenic N inputs and seagrass beds. Studies have shown signals of nitrogen enriched with 15N relative to 14N in various ecosystems may be a result of anthropogenic N sources(Sweeny & Kaplan 1980, McClelland et al. 1997, Costanzo et al. 2001, Yamamuro et al. 2003, Dillon & Chanton 2008), however, seasonal spatial and temporal nitrogen isotope fractionation variation may exhibit the same pattern of enrichment and confound results interpreted as pollution-derived (Anderson & Fourqurean 2003, Vizzini et al. 2003). The goal of this project is to determine whether nitrogen isotope fractionation upon N uptake by seagrasses changes in relation to varying light regimes on a seasonal basis. It is paramount to understand the amount of natural variation in nitrogen isotope ratios from natural systems so the signal is not interpreted as pollution derived, when other factors such as seasonality or biological fractionation could be at hand. METHODS Light and nutrient availability are being experimentally altered in Florida Bay at a site near Grassy Key Bank. At the site, a 3x3 factorial grid is set up with randomized light and nitrogen fertilization treatments that contain a control (ambient light), high light treatment, low light treatment, high N fertilization, and low N fertilization. Thalassia testudinum C and N content, seagrass morphology, δ15N of seagrasses and δ15N of DIN sources (pore water and water column) are measured monthly using SCUBA from August 2008-August 2009 to detect a seasonal pattern. Nutrient and isotope parameters are determined at the Seagrass Ecosystems Research Laboratory with a Fisons Carlo Erba Elemental Analyzer and the SERC Stable Isotope Laboratory using a Finnigan MAT Delta C IRMS, respectively, at FIU. EXPECTED RESULTS Expected results for this study are a positive correlation between light availability and seagrass growth such that high light intensities produce more robust seagrass morphology compared to low light situations. Additionally, C:N ratios for seagrass are expected to be higher in high light environments. Light availability is a resource that varies seasonally for seagrasses and we expect to see enriched nitrogen isotope values in summer and deplete values in winter. The isotopic separation, Δ, between seagrass source and source N is expected to be more pronounced at low light levels. Moreover, we expect our nitrogen stable isotope values to fall within the published range of values for Florida Bay. The importance of this study will show how much natural seasonal isotope variability there is in seagrass meadows and how fractionation factors are


52

related to light regimes, especially important if global climate change and anthropogenic influences alter water clarity and chemistry. DISCUSSION Proper management of seagrass beds in South Florida requires holistic knowledge of South Florida’s entire hydroscape (Fourqurean & Zieman 2002) and the interaction of coastal marine influences with human activities. The use of N isotopes in vegetation as an indicator of anthropogenic alterations of aquatic N cycling is becoming more prevalent, therefore, it is very important to understand natural causes of spatial and temporal variation in nitrogen ratios so seasonal fluctuations are not misinterpreted as pollution loading. Since Florida’s estuarine habitats are used commercially and recreationally, it is in the best interest of the local economy to keep them healthy. The effects that human driven environmental changes have upon water clarity, chemistry and sediment N cycling processes need to be identified for better management of coastal resources and for the future of Florida’s estuarine habitats. References: Anderson WT, Fourqurean JW (2003) Intra- and interannual variability in seagrass carbon and nitrogen stable

isotopes from south Florida, a preliminary study. Organic Geochemistry 34:185-194 Costanzo SD, O'Donohue MJ, Dennison WC, Loneragan NR, Thomas M (2001) A New Approach for Detecting and

Mapping Sewage Impacts. Marine Pollution Bulletin 42:149-156 Dillon KS, Chanton JP (2008) Nitrogen stable isotopes of macrophytes assess stormwater nitrogen inputs to an

urbanized estuary. Estuaries and Coasts 31:360-370 Fourqurean JW, Zieman JC (2002) Nutrient content of the seagrass Thalassia testudinum reveals regional patterns of

relative availability of nitrogen and phosphorus in the Florida Keys USA. Biogeochemistry 61:229-245 McClelland JW, Valiela I, Michener RH (1997) Nitrogen-stable isotope signatures in estuarine food webs: A record

of increasing urbanization in coastal watersheds. Limnology and Oceanography 42:930-937 Sweeny R, Kaplan I (1980) Natural Abundances of 15N as a Source Indicator for Near-Shore Marine Sedimentary

and Dissolved Nitrogen Marine Chemistry 9:81-94 Vizzini S, Sara G, Mateo MA, Mazzola A (2003) delta C-13 and delta N-15 variability in Posidonia oceanica

associated with seasonality and plant fraction. Aquatic Botany 76:195-202 Yamamuro M, Kayanne H, Yamano H (2003) delta N-15 of seagrass leaves for monitoring anthropogenic nutrient

increases in coral reef ecosystems. Marine Pollution Bulletin 46:452-458

Contact Information: Rebecca Bernard, Dept. of Biological Sciences, ECS 114, Florida International University, 11200 SW 8th St., Miami, FL 33199, Phone: 305-348-1556, Fax: 305-348-4096, Email: [email protected]


53

Recovery Status of Submerged Aquatic Vegetation in Manatee Bay, Barnes Sound and Northeastern Florida Bay Following Senescence of a Prolonged Algal Bloom Stephen Blair1, David T. Rudnick2, Christian Avila1, Forrest Shaw1, Maurice Pierre1, Kathryne Wilson1 and Susan Markley1

1Ecosystem Restoration & Planning Division, Miami-Dade County Department of Environmental Resources Management, Miami, FL

2Everglades Division, South Florida Water Management District, West Palm Beach, FL A highly unusual algal bloom formed in eastern Florida Bay (Blackwater and Little Blackwater sounds) and southern Biscayne Bay (Manatee Bay, and Barnes Sound) in the fall of 2005. Similar algal blooms have been observed in central and western Florida Bay, but never in these regions. These concentrations greatly exceeded values recorded through the twenty year duration of coastal water quality monitoring in this region (e.g., SFWMD/DERM/FIU datasets). Peak chlorophyll concentrations occurred in the fall and early winter. Concentrations decreased in the spring of 2006, but remained above the highest values observed prior to the bloom. Resurgence of the bloom occurred during the fall of 2007 in the southern Biscayne Bay basins. Chlorophyll concentrations did not return to historical levels (equivalent to median concentrations of pre-bloom records), until spring of 2008 (Figure 1).

Figure 1. Mean shoot density and Chl-a in southern Biscayne Bay (Barnes Sound [BS], Manatee Bay [MB]) and northeastern Florida Bay (Blackwater [BW] and Little Blackwater Sound [LB]. Causative agents for the bloom are not fully resolved, however, a combination of events are believed to have established conditions favorable for the bloom. An unusually strong, two-year long hypersalinity event preceded the bloom period. This event terminated in summer-fall of 2005, with unusually heavy seasonal rains and the passage of Hurricane Katrina. Concurrent with a dramatic and sudden decrease in salinity (lowest levels recorded in 3.25 years) were record low levels of dissolved oxygen (DO), pH, and oxidation-reduction potential (ORP).


54

Nutrient loading from storm runoff (e.g., Hurricane Katrina and heavy regional rainfall events), construction practices associated with construction of US-1, release of nutrients from salinity-stressed SAV, along with high residence times of the waters, recycling of nutrients, and nutrient inputs from resuspended sediments associated with decreased submerged aquatic vegetation (SAV) coverage and biomass, have been identified as probable causes, and factors contributing to the persistence of the bloom. The Miami-Dade DERM, through agreements with SFWMD, has conducted Braun-Blanquet Cover Abundance (BBCA) assessments of SAV populations within the NE Florida Bay embayments since 1993, and throughout Biscayne Bay since 1996. BBCA estimates and shoot density counts are gathered from 10 coastal basins in NE Florida Bay, as well as Manatee Bay and southern Barnes Sound in the southern Biscayne Bay region. Information from these assessments has documented significant decreases in SAV within specific basins of this region. Thalassia testudinum and Halodule wrightii shoot density data were evaluated for Florida Bay basins and southern most Biscayne Bay associated basins where the bloom conditions were documented. Changes in density of the sea grasses were compared to environmental conditions including salinity, photosynthetically active radiation (PAR), turbidity, and Dissolved Oxygen (DO). Initial modifications appeared to be associated with a sharp, but short term (<3 month) decrease in multiple environmental parameters (salinity, DO, pH, ORP) concurrent with the sudden storm-related freshwater influx into the region in the summer of 2005. Although the environmental parameters moderated within 3 months, light levels remained depressed, and chlorophyll-a concentrations elevated in these basins (1 to 2 orders of magnitude above historic medians) (Figure 1). A combination of the initial impact on standing crop, and long term potential light limitations appear to be drivers of SAV community modifications during this period. Response of the SAV to these events was basin specific. Blackwater Sound and Barnes Sound showed the most dramatic changes. These basins are deeper and have, on average, higher and less variable salinity regimes, thus SAV in these basins acclimate to the more consistent salinity conditions. The magnitude of modifications associated with the summer 2005 freshwater influx (record low salinity, DO pH and ORP) appear to have resulted in greater modifications within these basins than others (e.g., Thalassia density declined between 70 and 90 % within these basins). Response in the shallower basins, Manatee Bay and Little Blackwater, was less dramatic. PAR measures taken during SAV assessments indicate that relative to pre-bloom levels, benthic PAR was reduced 40% - 75% between July-05 to July-07. Light intensities began increasing, and chlorophyll-a concentrations moderating during the summer-fall of 2007, concurrent with increasing densities of Halodule in northern Blackwater, southern Barnes, and Little Blackwater sounds. Thalassia densities appear to initiate recovery in early 2008, in northern Blackwater Sound; however, no consistent signal of Thalassia recovery is identifiable in the other basins. Manatee Bay was unique in that Thalassia showed a continuous decline in shoot densities throughout the period, with no specific ‘signal’ of either the ‘break’ of the hypersalinity event, or the period of the presence of the algal bloom. Contact Information: Stephen Blair, Ecosystem Restoration & Planning Division, Miami-Dade Department of Environmental Resources Management, 701 NW 1st Ct., Miami, FL, 33160, USA, Phone: 305-372-6853, Fax: 305-372-6659, Email: [email protected]


55

Nutrient Loading in the Coastal Creeks of Northeastern Florida Bay Carrie Boudreau, Mark Zucker and Jeff Woods

U.S. Geological Survey, Florida Integrated Science Center, Ft. Lauderdale, FL, USA In 2003, three continuous water quality sampling stations, West Highway Creek near Long Sound, and North River and Upstream North River near Whitewater Bay, were established as part of the first 3-year cycle of the Monitoring Assessment Plan (MAP). In the second 3-year cycle of MAP, water quality sampling at Upstream North River was discontinued and continuous sampling at North River was replaced with routine grab sampling, while water quality sampling continued at West Highway Creek. In November 2006, two additional water quality sampling stations were established, Manatee Bay Creek and Card Sound Canal near Barnes Sound. The product of 3-day net discharges and 3-day composite samples were used to compute Total Phosphorus (TP) and Total Kjeldahl Nitrogen (TKN) loads at the three continuous water quality stations. Nutrient loading, defined as nutrient concentration multiplied by discharge over time, was predominantly from the Everglades wetlands into the coastal areas. However, short-term reversals in nutrient loading were observed as a result of storm surge associated with tropical storms and hurricanes. At West Highway Creek, annual TP loads varied from 0.11 metric tons during part of 2003, to 0.64 metric tons in 2005. Annual TKN loads at West Highway Creek varied from 13.5 metric tons during part of 2003, to 67.4 metric tons in 2005. Annual TP loads at Manatee Bay Creek and Card Sound Canal during 2006- 08 varied from 0.02 and 0.04 metric tons, respectively, in part of 2006, to 0.07 and 0.32 metric tons, respectively, in 2007. At Manatee Bay Creek, annual TKN loading in 2007 was 11.4 metric tons, whereas Card Sound Canal had an annual TKN load of 21.7 metric tons. This project provides baseline data along portions of the South Florida coastline where information was not previously available. The data will allow resource managers who oversee restoration projects, such as the C-111 Spreader Canal, to more accurately detect nutrient load changes that occur as a result of restoration efforts. Results from this study can be incorporated into future system-wide assessments of nutrient loading to Florida Bay and the southwestern coast of Florida. Contact Information: Carrie Boudreau, U.S. Geological Survey, Florida Integrated Science Center, 3110 SW 9th Ave, Ft. Lauderdale, FL 33315, USA, Phone: 954-377-5970, Fax: 954-377-5901, Email: [email protected]


56

Species Composition of Cyanobacterial Blooms in Florida Bay Joseph N. Boyer1, Makoto Ikenaga2, Amanda Dean1 and Cristina Pisani1

1Southeast Environmental Research Center, Florida International University, Miami, FL, USA 2Department of Life Science, Ritsumeikan University, Shiga, Japan

Following the 2005 hurricane season, a large cyanobacterial bloom appeared in eastern Florida Bay. This bloom was triggered by a large increase in total phosphorus resulting from the combination of enhanced freshwater inputs due to flood control and disturbance from road construction along US Highway 1 between the Florida mainland and Key Largo. Low phytoplankton biomass and low productivity in eastern Florida Bay are the general rule, mainly due to the small amount of phosphorus available in the water column. At the time of the bloom, P and chlorophyll a concentrations greatly exceeded the normal values. The cyanobacterial community structure was investigated using PCR - DGGE primers specific to the 16S and ITS region, followed by sequencing. Cluster analysis confirmed distinct community types existed in different regions of the bay. The Eastern Bay community was dominated by 2 organisms from the same clade V of MC-A cluster: Synechococcus sp. WH 8101 and Synechococcus sp. CB 0201. These organisms possess high affinities for inorganic N and P, can use amino acids, possess alkaline phosphatase, produce siderphores (Fe > 10 nM), and do not contain phycoerythrin (need high light). The North Central bay community was composed of Synechococcus sp. WH 8101, Synechococcus sp. RS 9708, and Cyanobium sp. PCC 9005. South Central and Western Florida Bay community dominated by Synechococcus sp. WH 8101 and Synechococcus sp. RS 9708 (same clade as WS 8101). The sediment community was composed of Synechococcus sp. RS 9708, Synechococcus elongatus PCC 6301 (prefers nitrate), Aphanizomenon ovalisporum ILC-149 (high P requirement, N2 fixer), Acaryochloris sp. (contains CHLd, symbiotic with acidians), Arthrospira sp. PCC 7345 (Spirulina, filamentous). Cyanobacterial species common to the bloom were not found in sediments, therefore the benthos was not “seeding” the bloom. This bloom event demonstrates the extreme sensitivity of oligotrophic estuaries, like Florida Bay, to changes in nutrient loading and the resulting impacts. Contact Information: Joseph N. Boyer, Southeast Environmental Research Center, OE-148, Florida International University, Miami, FL 33199, USA, Phone: 305-348-4076, Fax: 305-348-4096, Email: [email protected]


57

Storm Strength, Proximity, and Water Residence Time Differentially Affect the Magnitude of Impact and Recovery Time of Phytoplankton Biomass in Separate Zones of Florida Bay Henry O. Briceño and Joseph N. Boyer

Southeast Environmental Research Center, Florida International University, Miami, FL, USA Tropical storms and hurricanes frequently impact Florida Bay and its watershed. High winds, abundant precipitation, storm surge, and waves modify its geomorphology, its circulation and salinity patterns, and its nutrient levels. Conditions imposed by hurricanes on the system render significant responses from planktonic organisms which are immediately reflected as sudden increases in phytoplankton biomass (chlorophyll a, CHLa) in the water column. We have explored those storm-induced changes within a temporal-spatial framework using monthly water quality data for the period 1989-2007. Factor analysis and hierarchical clustering were used to subdivide the bay into six geographically separate zones having distinct water quality (Fig. 1). This statistically-derived subdivision of the bay coincides precisely with previous a zonation based on the distribution of phytoplankton communities by Phlips et al. (1999) and the Southern Estuaries Module of RECOVER in the Comprehensive Everglade Restoration Plan http://www.evergladesplan.org/pm/recover/recover_docs/ret/pm_se_waterquality.pdf.

Figure 1. The six subdivisions of Florida Bay based on water quality similarity: Eastern Bay (FBE; stars), East-Central (FBEC; filled circles), Northern (NB; open circles), Central (FBC; triangles), Southern (FBS; rhombs) and Western (FBW; squares). The nutrient and CHLa time series data were transformed into z-scores, and cumulative summary charts (CUSUM) were constructed. The CUSUM is a sequential analysis technique typically used for detecting change in time series. We then overlaid dates of hurricane landfalls affecting Florida Bay from 1992 to 2007 onto the CUSUM time series. Impacts of hurricanes on phytoplankton biomass were not uniformly distributed across the bay but showed substantial differences among zones (see examples in Fig. 2). This was due to hurricane strength and proximity, but also to the substantial differences in water residence time among zones. Therefore, for any given zone, the impact of individual hurricanes was not always the same and neither was the time it took for individual zones to return to pre-hurricane conditions.


58

-10

0

10

20

30

Jan-

91

Jan-

93

Jan-

95

Jan-

97

Jan-

99

Jan-

01

Jan-

03

Jan-

05

Jan-

07

Jan-

09

Z-C

usum

Florida Bay Central

Aug 05Katrina

Sep 05Rita

Oct 05Wilma

Oct 99Irene

Nov 98Mitch

Sep 98Georges

Aug 92Andrew

-60

-50

-40

-30

-20

-10

0

10

Jan-

91

Jan-

93

Jan-

95

Jan-

97

Jan-

99

Jan-

01

Jan-

03

Jan-

05

Jan-

07

Jan-

09

Z-C

usum

Florida Bay East

Aug 05Katrina

Sep 05Rita

Oct 05WilmaOct 99

Irene

Nov 98Mitch

Sep 98Georges

Aug 92Andrew

Figure 2. Z score CUSUM chart for CHL-a in Central and East Florida Bay. We defined the amplitude of the disturbance observed in the CHLa CUSUM chart as a Magnitude of Impact (MI). We then used the time it took to for CHLa to return to pre-hurricane conditions as the Recovery Time (RT). The log-log linear regressions of MI and RT were highly significant and predictive (r2=0.96), meaning that the MI:RT ratio may be used to express the resilience of each of the zones to past hurricane events. Different zones had significantly different MI:RT ratios, which remained consistent over time. Further development of this model may give us a tool for predicting spatial and temporal effects of future storms on these areas and on Florida Bay as a whole. References: Phlips, E.J., S. Badylak, and T. Lynch. 1999. Blooms of the picoplanktonic cyanobacterium Synechococcus in

Florida Bay, a subtropical inner-shelf lagoon. Limnol Oceanogr 44:1166-1175.

Contact Information: Henry Briceño, Southeast Environmental Research Center, Florida International University, 11200 SW 8th St, OE#140, Miami, FL 33199, USA, Phone: 305-348-1269, Email: [email protected]


59

Concentration and Upstream Migration of Pink Shrimp Postlarvae in Northwestern Florida Bay Maria M. Criales1, Joan A. Browder2, Michael B. Robblee3, Thomas Jackson2 and Hernando Cardenas1

1RSMAS, University of Miami, Miami, FL 2NOAA Fisheries, Miami, FL 3U.S. Geological Survey, Ft. Lauderdale, FL

We are investigating transport mechanisms and recruitment variability of pink shrimp (Farfantepenaeus duorarum) in South Florida to support population models of this commercially important species and to evaluate the impact of upstream water management changes on Florida Bay. Florida Bay is a nursery ground for pink shrimp that spawn and are fished near the Dry Tortugas; however the various regions of the Bay may not be equal in their production of pink shrimp recruits to the offshore grounds. In this research we explored the hypothesis that the influx of postlarvae to Florida Bay would be greatest at the western margin of the Bay where tidal currents are greatest and that concentrations would decrease with distance into the Bay. By exploring this hypothesis, we addressed the question of whether the abundance of pink shrimp juveniles in the Bay’s interior is limited by the influx of postlarvae or by the availability of favorable habitat, as defined by bottom vegetation, temperature, and salinity. Tides facilitate postlarval movements, and tidal amplitude is greatest at the Bay’s western boundary and damped with distance into the Bay. The Bay’s interior experiences extreme conditions of salinity with long periods of hypersalinity (>45 psu) punctuated by rare periods of relatively low salinity (<20 psu); both extremes may depress juvenile pink shrimp survival, growth, and abundance. Pink shrimp postlarvae were collected monthly during two or three nights around the new moon from July through November in 2004 and from June through October in 2005 at six stations along a west-east transect from northwestern Florida Bay (Middle Ground) to interior Florida Bay (Dump Keys). Channel nets were set out around sunset and retrieved after dawn. Results were mixed relative to the null hypothesis because the concentrations were not highest at the westernmost stations. Rather postlarval concentrations were highest about 15 km into the Bay from Middle Ground at the two mid-transect stations, which were located in narrow channels where tidal amplitudes were 15-20 cm, surrounded by dense seagrass beds. Moving further into the interior to the two easternmost stations, postlarval concentrations decreased, accompanied by a substantial decrease of tidal amplitude to about 1 cm and an increase in salinity and temperature. By means of hourly sampling overnight for five nights we confirmed the assumption that pink shrimp postlarvae use a flood-tide transport (FTT) to move shoreward into Florida Bay. The number of postlarvae collected was significantly higher during the flood tide than during the ebb tide in all five cases. Most postlarvae were collected during the strong flood current when onshore transport could potentially be maximized and predation during transport minimized. Estimates of the cumulative tidal displacement with the dominant semidiurnal M2 constituent indicated that the tidal wave moved 2.5-5 km per night to a maximum of 16 km eastward overnight, a distance that corresponds to the distance into the Bay of the highest concentrations of postlarvae. Postlarval size also showed a west to east progression, reaching the maximum size at the same location where high concentrations of postlarvae were recorded. These results support an alternative hypothesis that pink shrimp postlarvae may advance progressively up-estuary with the nocturnal flood tide on successive nights as a type of saltatory upstream


60

mechanism until they reach suitable habitat. This mechanism has been described for crabs and other shrimps that use FTT but not for the pink shrimp or any penaeid species of the Gulf of Mexico. To evaluate the effect of environmental variables on postlarval concentrations, daily time series were examined in relation to seven environmental factors (wind strength, cross-shelf winds, alongshore winds, sea water level, bottom temperature, salinity, and precipitation). Results of a Generalized Linear Model (GLM) indicated that concentrations of postlarvae were significantly related to salinity, wind strength, and cross-shelf wind stress. More postlarvae were captured during periods of low salinity and at the westernmost stations where salinity was lower. During the summer of 2004 salinity at the Buoy Key station (interior portion of transect) reached 60 psu for several days in July and over 50 psu between June 1 and July 15. The correlation with wind speed suggests that strong winds may create a vertical turbulence in the shallow and non-stratified water column of Florida Bay. Postlarvae that, due to FTT behavior, would ordinarily rest near the bottom at all times except the nocturnal flood tide may have been carried up into the water column throughout the night rather than just on the flood tide by the vertical turbulence associated with strong winds. Consequently, since our channel net was fishing the water column throughout the night, both ebb and flood tide, postlarvae may actually have been caught while moving in both directions. Three postlarval peaks occurred during strong SE winds, the typical winds of the season, and peaks were correlated with the offshore wind stress. If SE winds push postlarvae west and north, postlarvae could compensate for the offshore drift by using the easterly tidal currents to move back into the western Bay, where the tidal currents are strong, but not back into the interior Bay, where tidal currents are weak to nonexistent and water movements are dominated by winds. The integrated effect of tide and wind on postlarval transport across Florida Bay should be further addressed by a study that couples a biological model containing the FTT behavior with a hydrodynamic model of Florida Bay embodying the complex topography, tides, winds, and freshwater discharges characteristic of this system. Contact Information: Maria M. Criales, Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science (RSMAS), University of Miami, 4600 Rickenbacker Causeway, Miami, Fl 33149, Phone: 305-421-4073, Fax: 305-421-4600. Email: [email protected]


61

Déjà vu All over Again: The Impact of Recent Cyanobacteria Blooms on Hard-Bottom Communities in Florida Bay and the Florida Keys Mark J. Butler IV1 and Donald C. Behringer Jr.2

1Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA 2Program in Fisheries and Aquatic Sciences, University of Florida, Gainesville, FL, USA

During the early 1990’s, in what has been described as a “cascade of disturbances” in Florida Bay, drought and water management practices on the Florida mainland are thought to have instigated the large-scale die-off of seagrasses and the development of harmful cyanobacteria blooms. Those blooms decimated sponge communities in south-central Florida Bay and adjacent regions of the Florida Keys, compromising the filtering capacity of the system and impacting species that use sponges as shelter. Periodic sponge die-offs have been recorded in south Florida since at least the mid 1800’s, but the cascade of disturbances documented in the early 1990’s highlighted the intricate and often unexpected inter-connectedness of marine ecosystems. In the summer and fall of 2007, cyanobacteria blooms returned to this region and again left their destructive aftermath in the hard-bottom communities of Florida Bay and the middle Florida Keys. Surveys of the sessile hard-bottom community at sites that we monitor annually revealed that, as before, the sponge community was particularly hard hit. At the most severely impacted sites, 22 of 24 species of sponges surveyed were killed, whereas all species remained on "control" sites beyond the reach of the blooms. Differences in species-specific survival on sites that varied in bloom exposure (see figure) suggest a gradient in sponge species tolerance that is consistent with field observations of sponge distributions after previous blooms and laboratory studies of sponge tolerance to changes in salinity.

The loss of large, structure forming sponges such as vase sponges (Ircinia campana) and loggerhead sponges (Speciospongia vesparium) was especially dramatic. On some impacted sites, very large loggerhead sponges, many approaching a meter in diameter, that had survived the 1990-91 blooms died in this most recent event. Large sponges are important filter feeders of


62

the picoplankton in these shallow waters, so their demise must certainly diminish this critical ecosystem function. Loggerhead sponges in particular also provide shelter for organisms including obligate infauna (e.g., alpheid shrimps) and other species such as juvenile spiny lobsters (Panulirus argus) that utilize sponges opportunistically. On sites where the loss of loggerhead sponges was severe, the cascading effects on the juvenile lobster population and snapping shrimp abundance was striking. Hard-bottom communities severely impacted by sponge die-off were notably quiet (as revealed by recordings of underwater sound signatures) compared to un-impacted sites, primarily due to the loss of sound produced by snapping shrimp. Juvenile lobster abundance declined on severely impacted sites, and those that remained were often highly aggregated in shelters that are not typically used. Results from preliminary studies conducted shortly after the subsidence of the cyanobacteria bloom in fall 2007, indicated that lobster nutritional condition and the prevalence of a communicable viral disease (PaV1) did not differ between impacted and un-impacted sites. We are now analyzing data on possible effects on the juvenile lobster population from a more thorough set of post-bloom studies conducted in the spring and summer 2008. Contact Information: Mark J. Butler, Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529-0266 USA, Phone: (757) 683-3609, Fax: (757) 683-5283, Email: [email protected]


63

Interspecific Variation in the Elemental and Stable Isotopic Content of Seagrass Communities in South Florida Justin E. Campbell and James W. Fourqurean

Florida International University, Miami FL The elemental and isotopic leaf content of the seagrasses Thalassia testudinum, Halodule wrightii, and Syringodium filiforme were measured across a 10,000 km2 survey of the seagrass communities of South Florida. Elemental and stable isotope contents of all three species were highly variable across the study area, and demonstrated marked interspecific variation. Across all sites, mean nitrogen: phosphorus (N:P) ratios were lowest for T.testudinum (36:1 ± 1.1) and S. filiforme (39:1 ± 1.4), and highest for H. wrightii (44:1 ± 1.8). Stable carbon isotope ratios were highest for S. filiforme (-6.18 ± .21), intermediate for T. testudinum (-8.58 ± .20), and lowest for H. wrightii (-10.57 ± .28). Stable nitrogen isotopes displayed no interspecific variation across the study area, and ranged from 0.99-1.95 for all species. Stable carbon isotope values were negatively correlated to site depth for all species, while stable nitrogen content displayed no relationship to depth. This work documents interspecific variation in the nutrient dynamics of three common seagrasses in South Florida, indicating that interpretation of elemental and stable isotope values needs to be species specific. Within species, large spatial variation in the stable carbon isotope composition may be driven by the factors that regulate seagrass productivity (light levels and elemental ratios); while amongst species, variation in stable carbon isotope values may result from physiological differences in carbon acquisition mechanisms. Amongst all species, variation in the elemental ratios across the study area reveals spatial patterns in the relative availability of nitrogen and phosphorus. Interspecific differences in elemental ratios may result from species specific rates of growth and differential resource use efficiencies. Future studies which characterize the carbon acquisition mechanisms of these seagrasses should provide the mechanistic reasoning behind interspecific variation in stable carbon isotope values. Contact Information: Justin E. Campbell, Department of Biological Sciences, Florida International University, 11200 SW 8th street , OE 148, Miami, FL, 33199, USA, Phone: 305-206-3575


64

Advection and Exchange in Florida Bay Inferred from Long-term Water Quality Data B. J. Cosby1, J. Boyer2, H. Briceno2, F. Marshall3 and W. Nuttle4

1University of Virginia, Charlottesville, VA, USA 2Florida International University, Miami, FL, USA 3Cetacean Logic Foundation, New Smyrna Beach, FL, USA 4Eco-hydrology, Ottawa, ON, Canada

Patterns of variation in water quality in Florida Bay reflect the structure and dynamics of the ecosystem and the influence of the inflow of freshwater and nutrients from the Everglades. Past efforts to articulate the pathways that link watershed inputs to changes in the ecosystem have taken a bottom up approach based on development of predictive mechanistic models. Data accumulated over fifteen years of systematic monitoring of water quality in Florida Bay offers the possibility to infer characteristics of these pathways and related processes from a diagnostic analysis of the changes that have been observed. Diagnostic analysis of water quality data relies on a framework for mass-balance accounting of water quality constituents. A recent analysis of water quality data for the Patuxent River illustrates the basic overall approach (Testa and Kemp 2008). This presentation reports the results obtained in the first steps to implement a similar analysis in Florida Bay. These are to 1) divide the bay into a set of broadly homogeneous sub-regions, and 2) estimate rates of material transport between adjacent regions through advection and dispersive exchange. The analysis to divide the bay into sub-regions follows the prior analysis by Boyer et al. (1997) that divided the bay into three “zones of similar influence.” Our reanalysis of the now longer, current water quality data set divides the bay into five sub-regions (see Figure 1). This new classification matches precisely the zones of phytoplankton communities described by Phlips et al. (1999) except that we have an extra zone (our FBE). We apply the FATHOM model, calibrated to provide the best match of salinity variations, to estimate long-term (monthly) advective and dispersive exchange fluxes among these sub-regions within the bay. The FATHOM model provides a framework for accounting for advection and exchange processes in mass budget calculations of various water quality constituents. This model has proven successful in simulating long-term, bay-wide variation in salinity in response to variations in rainfall and freshwater inputs from the Everglades (Nuttle et al. 2000, Cosby et al. 2005). The magnitude of transport inferred for the central and northeast regions of the bay are consistent with findings by others that these areas have long residence times. The calculated water fluxes can be used to constrain the transport fluxes in an accounting of nutrient dynamics in these biogeochemically significant sub-regions of Florida Bay. References: Boyer, J. N., Fourqurean, J. W. & Jones, R. D. 1997. Spatial characterization of water quality in Florida Bay and

Whitewater Bay by multivariate analyses: Zones of similar influence. Estuaries 20, 743-758. Cosby, B., W. Nuttle, and F. Marshall, 2005. FATHOM Enhancements and Implementation to Support

Development of MFL for Florida Bay. Final Report on Contract C-C-15975-WO05-05 for the South Florida Water Management District. Environmental Consulting & Technology, Inc. New Smyrna Beach, Florida.

http://www.eco-hydrology.com/final%20report%20MFL%20FATHOM%209-30-05.pdf Nuttle, W. K., J. W. Fourqurean, B. J. Cosby, J. C. Zieman and M. B. Robblee. 2000. Influence of net fresh water

supply on salinity in Florida Bay. Water Resources Research 36:1805-1822.


65

Phlips, E.J., S. Badylak, and T.C. Lynch, 1999. Blooms of the picoplankton cyanobacterium Synechococcus in Florida Bay, a subtropical inner-shelf lagoon. Limnology and Oceanography 44:1166-1175.

Testa, J.M., and W.M. Kemp, 2008. Variability of biogeochemical processes and physical transport in a partially stratified estuary: a box-modeling analysis. Marine Ecology Progress Series 356: 63–79.

Figure 1: Five regions defined by analysis of available water quality data.

Contact Information: William Nuttle, 11 Craig Street, Ottawa, ON, Canada K1S 4B6, Phone: 613-233-4544, Email: [email protected]


66

A Flood Tidal Transport for Pink Shrimp Larvae on the SW Florida Shelf Maria M. Criales1, Joan A. Browder2 and Michael B. Robblee3

1RSMAS, University of Miami, Miami, FL 2NOAA Fisheries, Miami, FL 3U.S. Geological Survey, Ft. Lauderdale, FL

The population dynamics of pink shrimp is strongly influenced by biological and physical processes that affect the different life history stages. An understanding of these processes is necessary to accurately interpret population variability and effectively manage this important fishery species and the ecosystems of south Florida where the different life stages are found. Pink shrimp spawn offshore near the Dry Tortugas and larvae migrate into the nursery grounds of Florida Bay, where they settle for several months before entering the adult population. During the first phase of this research we tested hypotheses of larval transport from spawning to nursery grounds: (1) via Florida Straits through Florida Keys into southeastern Florida Bay and (2) via the Southwestern (SW) Florida shelf into western Florida Bay. A 4-yr field study with monthly sampling near both boundaries demonstrated that the vast majority of postlarvae enter Florida Bay along its NW border, suggesting the existence of an effective transport mechanism across the SW Florida shelf. The broad and shallow SW Florida shelf is dominated by strong tidal currents and affected by freshwater sources, and planktonic pink shrimp stages may easily recognize tidal currents by means of environmental variables. To clarify transport mechanisms and larval behaviors of pink shrimp during their migration on the SW Florida shelf, biological and oceanographic data were collected from on board the NOAA RV ‘Gandy’ every 2 hours on July 2-5, 2004 at three stations along a cross-shelf transect. At the Marquesas station, midway between Dry Tortugas and Florida Bay, we detected anomalously cool water, a shallow thermocline with strong density gradients, strong current shear, and a high concentration of pink shrimp larvae at the thermocline. Winds did not explain this anomalous water. Richardson numbers were low, suggesting that the vertical shear instability may have been caused by internal tides (Criales et al. 2007). Lineal internals tides do not contribute to a cross-shelf transport but may influence the concentrations of larvae at the pycnocline depth. Analysis of vertically stratified plankton by life stages suggested that larvae perform vertical migrations and the specific behavior changes ontogenetically. At the Marquesas station the relative concentrations of protozoea in the upper, middle, and bottom layers were consistent with a diel vertical migration, whereas that of postlarvae and myses were consistent with the semidiurnal tides in phase with the flood tide. Postlarvae, the shallowest dwellers that migrate with a semidiurnal periodicity, experienced the largest net onshore flux, and concentrations were highly correlated with the cross-shelf current. A vertical migration behavior coupled to the flood tides is known as Flood-Tide Transport (FTT), a type of generalized Selective Tidal Stream Transport (STST). In FTT organisms synchronize their vertical migrations to the tidal flow to take advantage of the shoreward horizontal advection provided by currents associated with the flood tide phase. An FTT behavior has been widely recognized for penaeid postlarvae at the entrance of estuarine nursery grounds but not during the preceding offshore migration. Our results provide the first evidence of an FTT behavior for shrimp larvae migrating in shelf waters offshore, ca. 80 km from the coast and at a depth of 20 m, while approaching the coastal nursery grounds.


67

With sources from another NOAA program (Fisheries and the Environment, FATE) and as a joint effort between NOAA/NMFS and CIMAS/UM, we have begun developing a biophysical Lagrangian model for the species. The Regional Ocean Modeling System (ROMS), a coastal scale hydrodynamic model incorporating tidal flux, will be the foundation of the biophysical model and will allow us to examine the interconnections between behavior and local, meso-scale, and regional scale processes in the migration of pink shrimp from offshore spawning grounds to their inshore nursery grounds. The goal is to develop physical and biological indicators of recruitment to help assess the status of the pink shrimp stock in south Florida. The model outputs will help to determine the origin of the anomalous water near the Marquesas and whether the FTT is the dominant onshore transport mechanism of this species. Reference: Criales, M. M., J. A. Browder, C. N. K. Mooers, M.B. Robblee, H. Cardenas and T. L. Jackson. 2007. Cross-shelf

transport of pink shrimp larvae: interactions of tidal currents, larval vertical migrations and internal tides. Mar. Ecol. Prog. Ser. 345:167-184.

Contact Information: Maria M. Criales, Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science (RSMAS), University of Miami, 4600 Rickenbacker Causeway, Miami, Fl 33149, Phone: 305-421-4073, Fax: 305-421-4600. Email: [email protected]


68

Florida Bay Salinity Extremes at Long Key Andrew G. Crowder and Jonathan S. Fajans

SEAKEYS Monitoring Program, Florida Institute of Oceanograhpy, Long Key, FL, USA The SEAKEYS (Sustained Ecological Research Related to Management of the Florida Keys Seascape) Monitoring Program’s station in Florida Bay off of Long Key (NDBC/C-Man Station: LONF1) has recorded high salinity levels in the summer months over the last several years, reaching all the way into the lower forties psu. These extreme high salinities are cause for concern, because they create extra stress on nearby corals and make them more prone to bleaching and other diseases. LONF1 is located to the north of the Long Key Viaduct, which is a major channel that allows water to flow in and out of Florida Bay. Therefore, this station’s location is crucial to documenting part of the net flow of water from Florida Bay to Hawk Channel and the reefs of the middle keys in the Florida Keys National Marine Sanctuary. These reefs are a vital part of the future of the Keys, as the mid channel patch reefs have recently been highlighted as being some of the healthiest reefs left in the Sanctuary at the Reef Resilience Conference this past April. Along with the combined stress being created through global climate change, elevated salinities and temperatures could be potentially harmful to these ever increasingly important environments. In the following charts Series 1 (blue) shows temperature and Series 2 (pink) shows salinity.

LONF1 Temperature and Salinity 2004-2007

0

5

10

15

20

25

30

35

40

45

1/1/

04

4/1/

04

7/1/

04

10/1

/04

1/1/

05

4/1/

05

7/1/

05

10/1

/05

1/1/

06

4/1/

06

7/1/

06

10/1

/06

1/1/

07

4/1/

07

7/1/

07

Date

Tem

pera

ture

(C) a

nd S

alin

ity (p

su)

Series1Series2


69

LONF1 Temperature and Salinity 2008

0

5

10

15

20

25

30

35

40

45

50

1/1/

08

1/15

/08

1/29

/08

2/12

/08

2/26

/08

3/11

/08

3/25

/08

4/8/

08

4/22

/08

5/6/

08

5/20

/08

6/3/

08

6/17

/08

7/1/

08

7/15

/08

7/29

/08

8/12

/08

Date

Tem

pera

ture

(C) a

nd S

alin

ity (p

su)

Series1Series2

These charts clearly display the salinity and temperature peaks in the summer months along with the extreme high salinities that have been seen this summer. Salinity levels first went over 40 psu in May this year and then have peaked over 43 psu over the last few months. If this trend continues this hypersaline warm water could be a cause for real concern for our already fragile ecosystem. A possible cause for these elevated salinity levels in Florida Bay is likely related to the low rainfall amounts we have experienced over the last few years. It also may be directly linked to the lack of a disperse sheet flow in favor of point source outflows which can lead to widespread hypersaline water with occasional slugs of fresh water being released during times of excess precipitation, such as the hurricanes of 2004 and 2005. This could be remedied by better management of the water coming into the Bay through the Everglades. Contact Information: Andrew G. Crowder, SEAKEYS Monitoring Program, Florida Institute of Oceanograhpy, 68486 US Highway 1, Long Key, FL 33001, USA, Phone: 305-664-9101, Fax: 305-664-0850, Email: [email protected]


70

Mercury Bioaccumulation in Florida Bay Fish: Why So High? David W. Evans1 and Darren Rumbold2

1NOAA, Center for Fisheries and Habitat Research, Beaufort, NC 2Department of Marine and Ecological Sciences, Florida Gulf Coast University, Fort Myers, FL

Eastern Florida Bay is a hotspot for mercury bioaccumulation in both recreational and forage fish. The bay is under consumption advisories for this reason, with a risk to both humans and fish eating wildlife. The high mercury concentrations have persisted since sampling began in late 1995. Originally it was hypothesized that high mercury concentrations were the result of runoff to the eastern bay from the mercury-enriched Everglades watershed’s drainage through Taylor River Slough. Although mercury concentrations were confirmed to be high in the watershed, it was determined that the methylmercury bioaccumulating in fish resulted from conditions within the eastern bay. The bay produced methylmercury from inorganic mercury with high efficiency and retained the methylmercury for long periods of time because of restricted dilution and flushing. Florida Bay was included in a CERP funded project monitoring mercury bioaccumulation in sentinel fish during the years 2005-2008. The eastern bay continued to have high mercury concentrations in gray snapper and crevalle jack, the highest in any of the 13 coastal marine regions that stretched from the Indian River Lagoon on the Atlantic coast to the Caloosahatchee Estuary on the Gulf coast. Many of these regions and their estuaries shared with Florida Bay the attribute of limited flushing which was thought to contribute to the high mercury concentrations in fish from eastern Florida Bay. The mercury concentrations were lower, however, and they may have lacked other attributes that have been postulated contribute to high mercury bioaccumulation. These other attributes include carbonate sediments, relatively modest organic carbon content in sediments, low nutrient concentrations, and frequent sediment resuspension (associated with shallow depth). This last attribute prevents the sustained development of anoxic sediments and sulfide build up that would inhibit the conversion of inorganic mercury to the bioavailable and more toxic methylmercury. It can also advect newly produced methylmercury to areas of biological uptake. Extensive sampling of water, sediments, and fish during the period 2000 to 2002 in eastern Florida Bay and its watershed found higher than normal methylmercury concentrations in all three media. Although the marginal mangrove ecotone generally had the highest methylmercury levels, active mercury methylation in the open bay seemed to be the source of methylmercury that ended up in the food web and in top predator gamefish. Organic matter from mangroves, seagrass, and phytoplankton (including benthic algae) all seemed to contribute to bacterial methylation of mercury and biomass formation that allowed methylmercury to attain high levels of bioaccumulation. In the past two years, we have looked outside of south Florida, to Mobile Bay, to test if the absence of some of the hypothesized attributes favoring mercury bioaccumulation would lead to lower mercury concentrations in fish, water, and sediments. This was indeed the case. High rates of freshwater dilution and flushing, inputs of siliceous rather than carbonate sediments, and a paucity of productive habitats (e.g. seagrass, marshes, and mangroves) supplying nutrients stimulating bacterial mercury methylation are thought to explain this bay’s low mercury bioaccumulation. Sampling other coastal estuaries should allow a more robust test of our


71

hypothesis and could lead to predictive capabilities identifying locales of high mercury bioaccumulation. Contact Information: Dr. David W. Evans, NOAA, Center for Coastal Fisheries and Habitat Research, 101 Pivers Island Road, Beaufort, NC, 28516, USA, Phone: 252-728-8752, Email [email protected]


72

Salinity, Light, and Temperature Effects on Ruppia maritima Germination in Florida Bay Marguerite S. Koch1, Josh Filina1, Jackie Boudreau1, Stephanie Schopmeyer1 and Chris J. Madden2

1Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA 2South Florida Water Management District, West Palm Beach, FL, USA

Ruppia maritima is a submerged aquatic vegetation (SAV) species that provides excellent waterfowl and fisheries habitat along the freshwater Everglades-mangrove ecotone in Florida Bay. This species has been identified as a keystone indicator of seagrass community health and a target species for salinity optimization in Florida Bay with Everglades’ restoration. Although Ruppia is known to dominate in the oligo- to meso-haline region of the bay, it can survive as an adult in hypersaline conditions (>60 psu). To provide data for mechanistic models to forecast seagrass species shifts in the bay under changes in fresh water flows, and in response to climate change scenarios, we investigated salinity (0-45 psu), light (water column [~500 μmol m-2 s-1] and sediment [dark]) and temperature (25 and 31oC) effects on Ruppia germination and seedling success. We are also monitoring Ruppia reproductive potential and germination in the field, and will be implementing seed transplant experiments, in order to further our mechanistic understanding of conditions which promote Ruppia dominance in low salinity regions of the bay. In mesocosm experiments, Ruppia germination predominantly occurred in the 3 low salinity treatments (0, 5, 15 psu) with few to no germinations at upper salinities (25, 35, 45 psu). However, after 5 months at treatment salinity, salinities were lowered to ≤1 psu, at which time the highest number of germinations occurred. The majority of these subsequent germinations, however, were in tanks previously at marine and hypersaline conditions (35 and 45 psu). These data provide a mechanistic understanding of field observations that Ruppia shows greater dominance at sites with highly variable salinities. In addition, although this species is not a true seagrass with strict fidelity to the marine environment, our results provide a better understanding of the role salinity can play in the distribution of this species at marine-freshwater ecotones. These results are now being field validated using long-term data sets, new reproduction monitoring studies, and manipulation experiments in the field. Contact Information: Marguerite S. Koch, Aquatic Plant Ecology Laboratory, Biological Sciences Department, Florida Atlantic University, 777 Glades Rd. Boca Raton FL 33431, Phone: 561-297-3325, Fax: 561-297-2749, Email: [email protected]


73

Monitoring Populations of Fish and Macroinvertebrates in Florida Bay R. E. Matheson, Jr., K. E. Flaherty and R. H. McMichael, Jr.

Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, St. Petersburg, FL, USA

Florida Bay supports a rich nekton community that includes various species of direct economic value and abundant species that provide the forage base for some of the economically valuable species. Natural patterns of freshwater delivery to the Florida Bay estuary that were important to these species have been disrupted by flood-control and water-supply projects that involved the construction of extensive levees and canal systems. Efforts to restore these natural flows may affect nekton species and communities. Eleven hydrologically defined FATHOM basins in northeastern Florida Bay were chosen for seasonal (four times a year) sampling because in these areas, restoration efforts are most likely to alter salinity regimes and therefore the patterns of nekton distribution and abundance. The primary objectives of this four-year study funded by the National Park Service are to conduct fisheries-independent surveys that will support environmental impact assessments by refining statistical models of nekton habitat use and to evaluate seasonal patterns of distribution and abundance of nekton in estuarine and marine habitats in Florida Bay. Habitat variables of interest include water chemistry (e.g., salinity, temperature, and pH), water depth, tidal conditions, and substrate type (e.g., vegetation characteristics, sediment type, and benthic community characteristics). The survey design will establish a baseline for statistically valid assessments of the status of nekton communities and individual species before and after Everglades restoration projects.

We used the following gear to sample nekton communities in both shallow- and deep-water habitats: 1) 21.3-m seines, 2) 6.1-m otter trawls, and 3) 183-m haul seines. The small seine and the trawl each have minimum mesh sizes of 3.2-mm and target small-bodied nekton; the large seine has 38-mm mesh and targets large-bodied nekton. We began testing the gear in June 2006, and by October 2006 all three types of gear were in use. Because we are still in the process of analyzing data, this presentation is based on only the data collected October 2006 through October 2007. Five sampling events were completed during this period, with sample sizes (i.e., net sets) of 331 small seines, 110 trawls, and 160 large seines. This multigear sampling approach provides data on small resident fishes, such as killifish, and larger resident and transient species, such as snapper and seatrout. The nekton community sampled by using small seines and trawls was numerically dominated by small resident fish that may be useful indicators of ecosystem health because they spend their entire lives within the bay and thus their populations are not directly influenced by human harvest. The most abundant taxa collected in both of these types of gear included the goldspotted killifish (Floridichthys carpio) and mojarras (Eucinostomus spp.). Few small juveniles of recreationally or commercially important fish were collected in small seines or trawls, but pink shrimp (Farfantepenaeus duorarum) were commonly collected with the trawl. Larger, more transient fish dominated the catch in the large seine, including larger juveniles of economically important species such as barracuda, snappers, jacks, drums, and sharks. The most abundant taxa collected with the large seine included silver jenny (Eucinostomus gula) and great barracuda (Sphyraena barracuda). Economically important species such as gray snapper (Lutjanus griseus), blue crab (Callinectes sapidus), and crevalle jack (Caranx hippos) were among the species most commonly collected in this gear. Based on these observations, northeast Florida Bay does not seem to function as a typical estuarine nursery area (i.e., with large numbers of small-juvenile fish), but it does serve as an important feeding ground for larger juveniles and adults.


74

Differences in the community structure of both the small- and the large-bodied nekton were detected between seasons (wet and dry months) and basins (PRIMER [MDS ordination and ANOSIM tests]). Differences in the small-bodied nekton communities among basins were more pronounced during the dry season than during the wet season. Differences in community structure revealed that two groups of basins were similar: high-salinity basins with large areas of open water and low-salinity basins adjacent to the mainland. As the wet season continued, these two community types became less distinct, but a gradient of community similarity was apparent from basins influenced by runoff to those basins less influenced. Joe Bay, however, had a notably different community structure than other basins in both seasons for small-bodied nekton. Joe Bay is an isolated basin closely associated with the Everglades, with one small channel (Trout Creek) connecting it to the rest of Florida Bay, and the salinity in this basin during the wet season was lower than in the rest of the sampling area. Large-bodied nekton community structure was distinctly variable between basins during the dry season, with no clear groups of basins emerging as being similar. In the wet season, however, basins with more stable salinity had communities with similar structure, and basins with more variable salinity had communities with distinct structures. The community structure in Little Madeira Bay was the most distinct, and the diversity of sportfish species was greater in this area, including the largest catches of spotted seatrout (Cynoscion nebulosus), black drum (Pogonias cromis), common snook (Centropomus undecimalis), and sheepshead (Archosargus probatocephalus). The transient nature of large-bodied nekton may have influenced the larger variation in community structure during the dry season, but the similarities between basins with more stable salinity confirm the strong influence of freshwater inflow during the wet season. The changes in community structure that we observed are associated with salinity regimes within and between basins and highlight the importance of monitoring fish communities before and after alterations in freshwater inflow. Contact Information: Kerry E. Flaherty, Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, 100 8th Ave. SE, St. Petersburg, FL 33701, USA, Phone: 727-896-8626, Fax: 727-893-1271, Email: [email protected]


75

Enhancing Adaptive Management Processes through Data Integration and Visualization Gregory Kiker1, James Hendee2, Yuncong Li3, Chuanmin Hu4, Pamela Fletcher5 and Lew Gramer6

1University of Florida, Gainesville, Florida, USA 2NOAA/AOML, Miami, Florida, USA 3University of Florida, Homestead, Florida, USA 4University of South Florida, St. Petersburg, Florida USA 5Florida Sea Grant, NOAA/AOML, Miami, Florida, USA 6University of Miami, Miami, Florida, USA

In 2002, the Florida Keys National Marine Sanctuary (FKNMS) established a conceptual model and science plan to identify major information gaps and to formulate adequate management responses to external stresses of their ecosystems. While model results and monitoring data have proliferated, greater understanding of the integration of scientific knowledge and management implementation has not kept pace. More recently, decision support activities have expanded to include both computational and social components to aid stakeholders in evaluating uncertain information at varying scales (time, space and discipline). An interdisciplinary team comprised of modelers, biophysical researchers and extension/outreach professionals are developing a decision support system (DSS) highlighting water quality and climate data in south Florida. This pilot study integrates and tests ecosystem scenario models linked with real-time data from NOAA’s Atlantic Oceanographic and Meteorological Laboratory’s Integrated Coral Observing Network (ICON), the University of South Florida’s Institute for Marine Remote Sensing and short-term forecast datasets from the Southeast Climate Consortium (SECC) within an interactive DSS. The purpose of the pilot project is to develop tools for adaptively managing ecosystem risks and vulnerabilities in South Florida. The project products are presented to target audiences in a facilitated ‘gaming styled’ DecisionPlaceTM session that is intended to enhance the understanding of the south Florida ecosystem and contribute to adaptively managing Everglades restoration efforts. The DSS provides educational information on climate products, ecosystem monitoring and forecasts, extreme events, and the connectivity of marine and coastal environments related to the Comprehensive Everglades Restoration Project. The DecisionPlaceTM integrates outputs from several ongoing research efforts to formulate a novel system for adaptive exploration of complex environmental challenges:

(1) data integration - climatic and ecosystem data from the ICON and SECC projects,

(2) data calculations - software development including scenario and game-style modeling,

(3) data visualization and interactions - electronic group participation aids for ease in interpreting datasets for decision-making.

Our approach is to engage and provide meaningful tools to managers and stakeholders. It uses Questions and Decisions (QnD), an innovative scenario modeling technology for developing a DSS tool with which stakeholders can explore and visualize potential management options. The QnD model links the spatial components within geographic information system (GIS) files to the abiotic, biotic and human interactions that exist in an environmental system. Iterative discussions aid in identifying and addressing the ongoing questions, risk and uncertainty that supports


76

adaptive and transparent ecosystem management decisions. This is the first DecisionPlaceTM presentation that provides background information on the process and pilot project outputs. It is intended to foster a discussion of the utility of DecisionPlace™ tools and format for adaptive management in dynamic systems. Contact Information: Pamela Fletcher, Florida Sea Grant, NOAA/AOML 4301 Rickenbacker Causeway, Miami, Florida, 33149, USA, Phone: 305-361-4335, Fax: 305-361-4447, Email: [email protected]


77

Halimeda Dynamics Relative to Nutrients Availability in the Florida Keys Ligia Collado-Vides 1,2 and James W. Fourqurean1,2

1Department of Biological Sciences, Florida International University, Miami, FL, USA 2Southeast Environmental Research Center, Florida International University, Miami, FL, USA

Coastal tropical communities are expected to shift from seagrass into macroalgae dominated communities as a response to nutrients increase and herbivory decrease (Orht et al. 2006). The Florida Keys National Marine Sanctuary (FKNMS) are carpeted by seagrass communities of varying density and species composition strongly controlled by nutrient availability (Fourqurean et al., 1995; Ferdie and Fourqurean, 2004). Different analysis of the seagrass monitoring program conducted in the FKNMS show that macraolgae and particularly Halimeda spp. are increasing in several sites (Collado-Vides et al 2005, 2007). In order to understand the dynamics of these changes we explored the spatial and temporal distribution of Halimeda spp. and the relationship between nutrients and Halimeda morphometric variables. We expected to find higher abundance, density and morphometric parameters in areas with higher nutrient concentrations. Halimeda specimens were sampled quarterly in 30 sites during 2006 using 2 (50 x 50 cm) quadrats. Species ID, frequency, density and abundance, were obtained for each quadrat, and dry weight, organic biomass, length, width, and order of branching, were measured at each thallus (>2500 thalli measured). Data from SERC-FIU data-base on water quality of the FKNMS were obtained, and correlations with TN and TP values were conducted to detect any relationship between nutrients and Halimeda variability. Nine Halimeda species were found along the FKNMS with H. incrassata and H. monile as dominant. Halimeda species were present in all 30 sites, but only H. incrassata was present in all sites. Sites closer to land had higher number of plants and biomass, but longer plants were found on sites far from land (Fig. 1 A and B). No spatial differences were found with plant order of branching or width. Seasonal changes were found with higher number of plants during summer however, an unexpected increase of abundance was detected in winter 2006 where a large number of small plants were recorded (Fig 1. C). Average number of plants/m2 was 19.92 (s.e. 3.17, s.d. 16.8), with a maximum of 67 and a minimum of 0 plants/m2.

5-9 9-120-5

Distance from shore in km

-3

11

25

39

53

67

81

# of

pla

nts/

m2

0

5

10

15

20

25

30

35

WI 05 SP 05 SU 05 FA 05 WI 06

Dry

wei

ght i

n g

Mass/m2# Plants/m2

Fig. 1 A) Density as a function of distance from shore. B) Plants length as a function of distance from shore C) Halimeda incrassata number of plants, and mass/m2 temporal variation. A positive correlation was found between biomass and TN (p< 0.05), and TP (p< 0.03) but no correlation was found with number, width or length of plants.

0.50 1.50 2.50 3.50

Distance from shore in Km

8

10

12

14

16

Thal

lus

leng

th in

cm

0-5 5-9 9-12

A B

C


78

Our results show that the steady increase of calcareous green macroalgae is dominated by H. incrassta and H. monile, not all species present are increasing in abundance, consequently a potential loose of Halimeda species could be happening in the long term. A seasonal pattern was found, however the unexpected winter 2006 pick could be a response to a high hurricane season in 2005. It is well known that Halimeda species can reproduce by fragmentation of their segments or branches; strong water action could break several Halimeda plants increasing the number of small plants, but not the amount of biomass. The average amount of plants/m2 is lower compared with other reports in the region (Davis and Fourqurean 2001), this can be explained by the fact that our data include all seasons and all kinds of environments including those where these species are not well represented. The significant positive correlation found between TN, TP and mass/m2 is consistent with previous monitoring (Collado-Vides et al 2005, 2007) and nutrient enrichment experimental results (Davis and Fourqurean 2001, Armitage et al. 2005). Experimental nutrient enrichment increases growth rates in Halimeda; and in Florida Bay did not stimulated algal growth to the level of overgrow seagrasses, but increases in calcareous green were detected. This is occurring on sites closer to land where nutrients are high, including increase in density and biomass. We need to explore deeply the competitive interactions among Halimeda species and evaluate the role of nutrients as a potential source for biodiversity loose at the intra-genus level and among all the seagrass bed community species. We also need to compare productivity budgets between calcareous green macroalgae and seagrasses as a way to detect a real shift in dominance from seagrass to calcareous green macroalgae. References: Armitage, A., Frankovich T, Heck, K. Jr. & Fourqurean J.W. 2005. Experimental nutrient enrichment causes

complex changes in seagrass, microalgae, and macroalgae community structure in Florida Bay. Estuaries 28, 422–434.

Collado-Vides, L., L.M Rutten,. and J. W. Fourqurean, (2005) Spatiotemporal variation of the abundance of calcareous green macroalgae in the Florida Keys: A study of synchrony within a macroalgal functional-form group. Journal of Phycology 41, 742-752

Collado-Vides, L., Caccia, V., Boyer, J.N. and Fourqurean, J.W. (2007) Spatiotemporal distribution of macroalgal groups in relation to water quality in the Florida Keys National Marine Sanctuary. Estuarine, Coastal and Shelf Sciences. 73: 680-694.

Davis B.C and Fourqurean J.W. 2001 Competition between the tropical alga, Halimedaincrassata, and the seagrass, Thalassia testudinum. Aquatic Botany 71: 217-232.

Ferdie, M. & J. W Fourqurean,. 2004. Responses of seagrass communities to fertilization along a gradient of relative availability of nitrogen and phosphorus in a carbonate environment. Limnology and Oceanography 49, 2082–2094.

Fourqurean, J. W., G.V.N. Powell, W.J. Kenworthy and J.C. Zieman. 1995. The effects of long-term manipulation of nutrient supply on competition between the seagrasses Thalassia testudinum and Halodule wrightii in Florida Bay. Oikos 72:349-358.

Orth, R. J., T. J. B. Carruthers, W. C. Dennison, C. M. Duarte, J. W. Fourqurean, K. L. Heck, A. R. Hughes, G. A. Kendrick, W. J. Kenworthy, S. Olyarnik, F. T. Short, M. Waycott, and S. L. Williams. 2006. A global crisis for seagrass ecosystems. BioScience. 56(12):987-996.

Contact Information: James W. Fourqurean, Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, 33199, USA, Phone: 305-348-4084, Fax: 305-348-4096, Email: [email protected]


79

Long-term Shifts in Seagrass Community Structure Follow Experimental Nutrient Enrichment in Florida Bay Anna R. Armitage1, Thomas A. Frankovich2 and James W. Fourqurean2

1Department of Marine Biology, Texas A&M University-Galveston, Galveston, TX, USA 2Department of Biological Sciences and Southeastern Environmental Research Center, Florida International

University, Miami, FL, USA Restoration of the greater Everglades ecosystem may increase freshwater input to Florida Bay. Increased freshwater flow, as envisioned by the Comprehensive Everglades Restoration Plan, may increase loadings of both nitrogen and phosphorus into the Bay. Over the last six years, we have been investigating the regional and temporal effects of these increased loadings on benthic communities. Community responses to anthropogenic nutrient enrichment are often evaluated with short-term experimental manipulations, but real-world effects of enrichment usually occur over long time scales. We used a multi-year experimental approach to assess the long-term (six years) effects of nutrient enrichment on the benthic community in Florida Bay. We examined the spatial extent and temporal patterns of nitrogen (N) and phosphorus (P) limitation of each of the major benthic primary producer groups in Florida Bay: seagrass, epiphytes, macroalgae, and benthic microalgae, and characterized the shifts in primary producer community composition following nutrient enrichment. We also evaluated epifaunal assemblage responses to nutrient enrichment. We established study plots at each of six sites across Florida Bay and added N and P to the sediments in a factorial design for six years. Tissue nutrient content of the turtlegrass Thalassia testudinum revealed a spatial pattern in P limitation, from severe limitation in the eastern bay (N:P > 96:1), moderate limitation at two intermediate sites (~63:1), and balanced with N availability in the western bay (~31:1). Florida Bay is primarily phosphorus-limited; nitrogen addition did not consistently affect any benthic primary producers. After three years of phosphorus addition, shoalgrass (Halodule wrightii) began a gradual replacement of the dominant turtlegrass (Thalassia). After six years of

enrichment, Halodule had colonized most P-addition plots in four of the six sites (Fig. 1). In the western bay (e.g., Sprigger Bank), where ambient Thalassia tissue N:P ratios indicated that N and P availability was balanced (~31:1), seagrass was not affected by nutrient addition but was strongly influenced by disturbance (currents, erosion). Macroalgal and epiphytic and benthic microalgal biomass were variable between sites and treatments. In general, there was no algal overgrowth of the seagrass in enriched conditions, possibly due to temporal stochasticity or regulation by grazers. However, within the epiphytic microalgal community, encrusting green and red algae increased following P addition at most sites (Fig. 2), whereas diatom biomass, though highly variable among sites, did not respond to nutrient treatments. N addition had little

effect on any benthic primary producers throughout the bay. There was no evidence of more than ephemeral algal overgrowth in enriched plots; epiphytes and macroalgae may have been seasonal or controlled by higher grazer densities in those treatments.

N02 F0

3M

03 A03

N03 F0

4M

04 A04

N04 F0

5M

05 A05

N05 F0

6M

06 A06

N06 F0

7M

07 A07

N07 F0

8M

08

Hal

odul

e w

right

ii BB

Sco

re

0

1

2

3

4CNPNP

Figure 1: Nitrogen and phosphorus enrichment effects on Halodule wrightii cover (represented by Braun-Blanquet score) at Duck Key in eastern Florida Bay.


80

In the severely P-limited eastern bay, densities of caridean shrimp, grazing isopods, and gammarid amphipods were higher in enriched than in unenriched plots. In the less P-limited western bay, epifaunal density was not affected by nutrient addition. At both sites, some variation in epifaunal density was explained by features of the macrophyte canopy, such as Thalassia and Halodule percent cover, suggesting that enrichment may change the refuge value of the macrophyte canopy for epifauna. Additional variation in epifaunal density was explained by epiphyte pigment concentrations, suggesting that enrichment may change microalgal food resources. Stable isotopic signatures (δ15N) revealed increased importance of Halodule in the diet of benthic consumers, primarily benthic grazing snails at the P-limited site. The diet of epiphyte grazers did not change in enriched plots, but increased density suggests that grazers may be able to control epiphytic algal proliferation following moderate nutrient input to Florida Bay. Our ongoing studies are providing increasingly in-depth perspectives into how nutrient input will affect the Florida Bay ecosystem at the organismal and community levels. In particular, we have demonstrated that increased nutrient input to Florida Bay will cause long-term shifts in benthic primary producer assemblages, and these shifts may occur over decadal time scales. These changes in primary producers will lead to rapid alterations of epifaunal assemblages and may continue to modify animal communities over longer time periods. Changes in herbivorous epifauna may influence epiphytic growth on seagrasses and modify support for higher trophic levels in the bay. Contact Information: Anna R. Armitage, Department of Marine Biology, Texas A&M University at Galveston, 5007 Avenue U, Galveston, TX 77062, USA, Phone: 409-740-4842, Fax: 409-740-5002, Email: [email protected]

Figure 2: Nitrogen and phosphorus effects on chlorophyll b biomass in Thalassia epiphytes at six sites in Florida Bay with varying background phosphorus levels.

Phosphorus limitation

Duc

k

S N

est

Bob

Alle

n

Rab

bit

9Mile

Sprig

ger

Chl

orop

hyll

b (u

g cm

-2)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16C N P NP

High Low


81

Multiple Lines of Evidence Suggest Long-Term Eutrophication of Seagrass-Dominated Nearshore Ecosystems in the Florida Keys James W. Fourqurean

Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, USA

Since 1995, monitoring of the species composition, relative abundance, elemental content and stable isotopic composition of seagrasses has been assessed quarterly at 35 sites in Florida Bay and the Florida Keys National Marine Sanctuary. Many of these sites are exhibiting long-term changes consistent with our models of the effect of increased nutrient availability in tropical seagrass beds. In general, nutrient addition to aquatic environments shifts the competitive balance to faster-growing primary producers. The consequences of this generality in seagrass-dominated environments is that seagrasses are the dominant primary producers in oligotrophic conditions. As nutrient availability increases, there is an increase in the importance of macroalgae, both free-living and epiphytic, with a concomitant decrease in seagrasses because of competition for light. Macroalgae lose out to even faster-growing microalgae as nutrient availability continues to increase: first, epiphytic microalgae replace epiphytic macroalgae on seagrasses; then planktonic microalgae bloom and deprive all benthic plants of light under the most eutrophic conditions. Each species in the species dominance-eutrophication gradient model can potentially dominate over a range of nutrient availability and the model predicts a change in species dominance as nutrient availability changes. These changes are not instantaneous, however. Field evidence suggests that species replacements may take place on a time scale of a decade or more. It is desirable that we be able to predict the tendency of the system to undergo these changes in species dominance before they occur, so that management actions can be taken. Tissue nutrient concentrations can be monitored to assess the relative availability of nutrients to the plants. For phytoplankton communities, this idea is captured in the interpretation of elemental ratios compared to the familiar ‘Redfield ratio’ of 106C:16N:P. For the seagrass T. testudinum, the critical ratio of N:P in green leaves that indicates a balance in the availability of N and P is ca. 30:1, and monitoring deviations from this ratio can be used to infer whether N or P availabilities are limiting this species’ growth. Hence, T. testudinum is likely to be replaced by faster-growing competitors if nutrient availability is such that the N:P of its leaves is ca. 30:1. A change in the N:P in time to a value closer to 30:1 is indicative of eutrophication. In addition to species composition and elemental content, the stable isotopic composition of plant tissues change as environmental conditions change. As light availability to the seagrasses is reduced, as occurs when nutrient availability increases and faster growing taxa proliferate, the stable carbon isotopic composition shifts towards values more depleted in the heavier stable C isotope, 13C. Hence, long-term changes in del13C values of seagrasses can serve as an indicator of changing light environment. Nitrogen stable isotopic composition can also indicate change in nutrient status; however this indicator is much more complicated to interpret. Sewage-derived nitrogen tends to be enriched in the heavier stable isotope, 15N, while fertilizer-derived nitrogen is depleted of this heavier isotope. Additionally, changes in the availability of light may affect plant stable N contents in a manner similar to the stable carbon isotopic content. While interpretation of patterns in stable N isotope composition are not straightforward, changes in the del15N of seagrass tissues does indicate a change in the nutrient environment of those plants.


82

Our monitoring data indicates a large spatial gradient in the N:P ratios of Thalassia testudinum across the sanctuary, with N:P ratios predicting nitrogen limitation in the offshore parts of the sanctuary and predicting phosphorus limitation in the nearshore areas. Nearshore seagrass beds do not respond strongly to fertilization, but seagrass beds near the reef and within Florida Bay respond strongly to N (reef) or P (Florida Bay) addition. Top down controls are also important in controlling species composition and biomass of the seagrass beds adjacent to coral reefs in the FKNMS, and we have found that herbivorous fish can exert a greater control than nutrient availability in controlling seagrass community composition along the reef tract of the FKNMS. At 13 of the 35 monitoring sites in the Florida Keys, there have been changes in the relative abundance of seagrasses and macroalgae over the period 1995 - 2007 that are consistent with increased nutrient availability. At none of these has there yet been a decrease in seagrass abundance, but our conceptual model predicts that increases in fast-growing macroalgae should precede decreases in seagrass abundance. In addition to these sites where relative abundance of primary producers has changed, at 5 of the sites there have been long-term shifts in the ratio of nitrogen to phosphorus in seagrass leaves that are consistent with increases in nutrient availability. Two sites that were heavily effected by the passage of hurricanes displayed trends in N:P away from Redfield over the monitoring period, suggesting that nutrient availability has decreased at these sites over the monitoring period. Multiple sites also show significant trends in decreasing del13C ratios of seagrass leaves, consistent with decreased light availability. Further, complicated changes in the nitrogen isotope ratios indicate changes in the supply of N to seagrasses in parts of the study area. While the trends in indicators we present are consistent with model predictions of nutrient-induced changes of these systems, there may be reasons for these observations that are unrelated to man's activities in the region. However, the spatial pattern of changes and the agreement of the changes with models of the system suggest that there is regional-scale change in nutrient availability that is causing changes in seagrass beds over a wide portion of the Florida Keys. Contact Information: James W. Fourqurean, Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, 33199, USA, Phone: 305-348-4084, Fax: 305-348-4096, Email: [email protected]


83

Spatio-Temporal Dynamics of SAV Abundance in the Mangrove Lakes Region of Florida Bay: Relationships to Salinity, Phosphorus, and Water Clarity Thomas A. Frankovich1, Douglas Morrison2 and James W. Fourqurean1

1Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL, USA

2Everglades National Park, Florida Bay Interagency Science Center, Key Largo, FL, USA The Florida Bay coastal embayments from Terrapin Bay to Garfield Bight and the mangrove zone lakes hydrologically connected to these embayments (e.g., Seven Palm Lake, West Lake, and The Lungs) are a focus of the Comprehensive Everglades Restoration Plan (CERP) activities (CERP 2002). This area, including the mangrove dominated wetlands, is important nursery habitat for recreational and commercially valuable fishery species (Tilmant 1989; Ley and McIvor 2002); designated critical for the endangered American crocodile (Mazzotti 1989); and, is important foraging and nesting habitat for wading birds, including the endangered wood stork and the roseate spoonbill (state species of special concern), and waterfowl (Kushlan et al 1982; Ogden 1994). These species and others depend on oligohaline to mesohaline spatial and temporal salinity patterns CERP 2004a). Altered freshwater inflow patterns (quantity, duration, and distribution) from water management practices have increased salinities and likely had adverse ecological effects in this area (McIvor et al 1994; CERP 2004a). Historically, under oligohaline to mesohaline conditions, these coastal lakes and embayments had extensive benthic macrophyte or submerged aquatic vegetation (SAV) beds. These macrophytes supported fishery species and waterfowl and helped maintain good water quality (Tabb and Manning 1961; Tabb et al 1962; Kushlan et al 1982; Tilmant 1989; CERP 2004a). Due to a lack of significant tidal flushing, these SAV communities experience more direct and rapid effects of changes in freshwater inputs than those in Florida Bay proper. It is hypothesized that prolonged periods of elevated salinity in the coastal lakes and basins, caused by diminished freshwater inflow volume and duration due to water management practices, have reduced the seasonal duration and spatial extent of benthic macrophytes (CERP 2004a). The decline in waterfowl abundance in the mangrove zone lakes is thought to be at least partially due to this reduction in SAV (CERP 2004a). During recent high rainfall years, and thus increased freshwater inputs, macrophyte and waterfowl abundances increased in the mangrove zone lakes (Morrison and Bean 1997; Montague et al 1998; CERP 2004a). Restoring more natural freshwater water inflow and salinity patterns in this area should have diverse ecological benefits, affecting benthic macrophytes, fishery species, waterfowl, water quality, the American crocodile, resident small fishes, and wading birds (CERP 2004a). The objectives of the present investigation are to describe the spatial and seasonal dynamics of SAV abundance and water quality in the Mangrove Lakes and to identify possible relationships between water quality and SAV abundance and community structure. From April 2006 to August 2008, water temperature, water clarity (Secchi depth), salinity, nutrients (total nitrogen and total phosphorus), and phytoplankton density (chlorophyll-a) were measured during monthly water quality surveys at 41 sites in the 7 Palm Lake system (7 Palm Lake, Middle Lake, Monroe Lake and Terrapin Bay) and the West Lake system (West Lake, Long Lake, The Lungs, and Garfield Bight). SAV species composition and percent cover were also measured on a quarterly basis during this period. Univariate and multivariate analyses were employed to detect spatial and


84

seasonal patterns and to describe relationships between water quality parameters and SAV community structure. Key findings: 1) SAV flora in the Mangrove Lakes is relatively species-poor (13 spp. observed). Chara hornemannii, Halodule wrightii, Batophora oerstedii, and Ruppia maritima constitute >99% of relative species abundance. Chara and Halodule were most abundant constituting approximately 90% of species relative abundance. 2) Spatial SAV distribution patterns are consistent with mean salinities, with Chara occupying the upstream "lakes" and Halodule occupying the more marine coastal embayments. Batophora and Ruppia occurred throughout the system but in much lower relative abundances. 3) Seasonal abundance patterns differ between Chara and Halodule, with Chara following salinity patterns and Halodule following temperature. Chara achieved greatest bottom coverages in spring months and then declined during the latter half of the dry seasons. Halodule achieved greatest bottom coverages during summer and declined to minimum coverages during winter. 4) Water quality and SAV abundance differed greatly between the upstream "lakes" of the 7 Palm Lake system and those of the West Lake system. Total phosphorus concentrations are ≈3X greater in the West Lake system than in the 7 Palm Lake system fueling ≈6X greater phytoplankton densities. Increased water clarities in the 7 Palm Lake System coincide with ≈5X greater Chara abundances. Contact Information: Tom Frankovich, Florida Bay Interagency Science Center, 98630 Overseas Highway, Key Largo, FL 33037 USA, Phone: 305-393-4636, Email: [email protected]


85

Relationships Between Submerged Aquatic Vegetation Abundance and Salinity Variability within the Coastal Mangrove Zone of Northeastern Florida Bay Peter Frezza and Jerome J. Lorenz

Audubon of Florida, Tavernier Science Center, Tavernier, FL Since 1996 we have been conducting a routine submerged aquatic vegetation (SAV) monitoring project within the coastal mangrove zone of northeastern Florida Bay. A purpose of this project was to determine the relationships between salinity and salinity variability and abundance and speciation of the SAV community within this estuary. SAV surveying was conducted every six weeks along 4 distinct salinity gradients, each beginning in an upstream, interior dwarf mangrove zone and ending in Florida Bay. Salinity and other hydrologic variables were continuously monitored at each surveying location using on-site dataloggers. Seasonal and annual salinity variability were examined for our period of record (1996-present) to determine the relationships with the SAV community. Major SAV species encountered at these sampling locations are Ruppia maritima, Halodule wrightii, Chara hornemanii, Utricularia spp. and Najas marina. A principal component analysis was run on 45 hydrologic variables encompassing a wide range of antecedent time periods for salinity level, salinity variance, water temperature and water level prior to day of SAV survey. The PCA generated 8 composite variables that were significant enough to be retained and used in a stepwise multiple regression with Total SAV percent cover as the dependent variable. The regression indicated that antecedent short term salinity level and short term standard deviation of salinity were the 2 variables that were explaining most of the variance in SAV coverage. Antecedent short term conditions were defined as the 30 to 90 days prior to day of SAV survey. As composite variables, salinity and salinity variability together explained 43% of the variance in SAV coverage. Hydrologic conditions on the day of SAV survey and conditions beyond the 90 day period prior to day of survey did not correlate well with total SAV coverage. To determine independent relationships between salinity and salinity variability on the SAV community, two separate piecewise linear regressions were run using total SAV cover as the dependent variable against salinity level and standard deviation of salinity respectively. Both regressions indicated significant (p<0.0001) negative relationships with SAV coverage: 60 day mean salinity prior to day of survey R2= .66; 60 day standard deviation of salinity prior to day of survey R2= .63. An analysis of annual mean salinity in comparison with annual SAV coverage also indicated significant negative relationships between the two. High total SAV coverage occurred when annual mean salinity was low. During our period of record, there were two years that experienced prolonged hypersaline conditions in the coastal mangrove zone of northeastern Florida Bay (2000-01 and 2004-05). These two years of elevated, highly variable salinity conditions corresponded to the two years when major die-off events occurred in the SAV population in this region. Contact Information: Peter Frezza, Audubon of Florida, 115 Indian Mound Trail, Tavernier, FL, 33070, Phone: 305-852-5318, Email: [email protected]


86

The Use of Otolith Microchemistry to Determine Sources of Lutjanid Recruits to the Dry Tortugas Ecological Reserve T. Gerard1, A. Wright2, E. Malca2 and John Lamkin1

1National Oceanic and Atmospheric Administration (NOAA), Southeast Fisheries Science Center, Early Life History; Miami, FL

2University of Miami, Cooperative Institute for Marine and Atmospheric Studies (CIMAS), Miami, FL In the coastal waters of southern Florida, economically and ecologically important reef fishes such as Lutjanidae (snapper) spawn offshore in association with reef habitats of the Florida Keys and the Dry Tortugas (Smith, 1997 and Richards, 2006). Numerous reef species are known to recruit to nursery habitats in Florida Bay during their early life history before migrating to the reef as adults. Much of the population dynamics of Lutjanidae is unclear, particularly the question as to whether juvenile populations in the Dry Tortugas are open or closed. Otolith microchemistry that uses stable isotopes of carbon (13 C) and oxygen (18 O) is used to delineate stocks in different water masses and to indicate changes in environmental conditions (Gerard, in review). Variations in 13 C and 18 O in the otoliths can reveal whether recruitment of newly settled juveniles originate in single or multiple habitat sources and/or locations along the reefs. This study will analyze the otoliths of two Lutjanidae species (Lutjanus griseus and Ocyurus chrysurus) from the Dry Tortugas Ecological Reserve and investigates variations in stable isotope signals of carbon and oxygen. Results will provide valuable recruitment data concerning these populations for improved fisheries management in Florida Bay and adjacent marine ecosystems. Contact Information: Trika L. Gerard, National Oceanic and Atmospheric Administration (NOAA), Southeast Fisheries Science Center, Early Life History; 75 Virginia Beach Drive, Miami, FL 33149, Phone: 305-361-4493, Fax: 305361-4478, Email: [email protected]


87

Assessing Gaps in Florida’s Marine and Estuarine Conservation Network Laura Geselbracht1 and Douglas Shaw2

1The Nature Conservancy, Wilton Manors, FL, USA 2The Nature Conservancy, Gainesville, FL, USA

The continued decline of nearshore marine and estuarine systems across the United States and abroad indicates that existing management regimes are insufficiently protecting the long-term health of these systems. One necessary approach for rectifying this situation is to designate a network of biogeographically representative sites with explicit quantitative measures that adequately protect system resources. To assess the adequacy of current site-based protection of Florida (USA) marine and estuarine systems, we conducted the first spatially and quantitatively explicit gap assessment of these systems in state territory. Numerous federal, state and local managed areas representing a variety of protection regimes are present in the marine and estuarine systems of Florida. We developed a scheme for rating the level of protection (i.e., gap status) offered by these various management regimes based on a similar process followed for terrestrial gap analyses. By overlaying the spatial distribution of managed areas with their associated gap status on a map of marine and estuarine habitat biodiversity elements, we quantified the current protection status of these biodiversity elements by biogeographic region. While scientists continue to debate how much area of each biodiversity element is needed to confer long-term health to marine and estuarine systems, our analysis shows that site-based management in Florida is spatially extensive, but at a very low level of protection. With global climate change impacts increasingly adding to the arsenal of threats already impacting Florida’s marine and estuarine systems, the lack of a sufficiently representative, systematic and quantitative approach to protecting Florida’s marine and estuarine resources greatly impedes the state’s ability to protect these resources into the future. The existing spatially extensive system of marine and estuarine managed areas perhaps offers the most expedient solution to achieving an adequately protected network of representative sites as official designations, staff and budgets are in place. Contact Information: Laura Geselbracht, 2408 NE 19 Avenue, Wilton Manors, FL 33305, USA, Phone: 954-383-3085, Email: [email protected]


88

Dissolved Organic Material and the Adaptive Physiology of Synechococcus Help to Sustain Blooms in Florida Bay Patricia M. Glibert1, Cynthia A. Heil2, Sue Murasko2, Jeffrey Alexander1, MerrieBeth Neely2 and Christopher Madden3

1University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge MD 2Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL 3Coastal Ecosystems Division, South Florida Water Management District, West Palm Beach, FL

Beginning in September of 2005, a large phytoplankton bloom appeared in the historically clear waters of northeastern Florida Bay. The dominant species were the same as those prevalent in the central bay blooms that have developed with some frequency over the past decades: a suite of picocyanobacteria dominated by Synechococcus spp. Peak concentrations exceeded 30 μg L-1. The initiation of these blooms was coincident with two major system perturbations. First, in 2005, Florida Bay was impacted by a series of hurricanes (Katrina, Rita, Wilma), which resulted in Canal C111 discharges, and thus large increases in freshwater and nutrient inputs, especially of dissolved phosphorus, to Manatee Bay and Barnes Sound. Second, in the same year, construction began on the expansion of an 18-mile causeway connecting the mainland and the Keys, resulting in the clear-cutting and mulching of acres of mangroves and extensive soil excavation and tilling. The input of organic matter to the eastern bay from this construction is unknown and unquantifiable, but the proximity of the blooms to the region of the construction implicates this as a contributing factor. Understanding the role of organic nutrients in these blooms has been the focus of NOAA-CSCOR supported research. Indeed, nutrient preferences based on short-term 15N uptake experiments with natural Synechococcus populations show that it preferentially responds to organic nitrogen forms compared with inorganic forms. Longer-term bioassay experiments, in which biomass responses to a range of both organic and inorganic nitrogen and phosphorus substrates, alone and in combination, have been assessed, reveal that organic forms of N and P also stimulate Synechococcus response. Mean biomass increases typically did not exceed 1 doubling in 48 hours. In fact, the highest biomass increases were in response to a combination of organic N and P substrates, indicating that addition of a single limiting nutrient alone is not enough for a bloom to occur. Even the addition of complex forms of organic material, such as humic acids, yielded significant increases in Synechococcus, on occasion equavalent to 3 doublings in 48 hours. The response to humic material mirrored the response to additions of phosphate, and suggested that humic material acted as a geochemical proxy for phosphate. The natural phosphorus content of the humics was very low so it was not a direct phosphate source. The change in enzyme activities after 48 hour exposure to various substrates indicate that the cells are poised to exploit either dissolved organic nitrogen or dissolved organic phosphorus, but are typically not able to exploit both simultaneously. Thus, the enhanced biomass accumulation when both nutrients are supplied represents a rapid shift-up and/or shift-down of enzymes and their associate pathways. While this recent bloom may have been triggered by the events of 2005, as light penetration to the benthos is reduced, more seagrasses are lost, in turn leading to increased nutrient availability and release from the sediment, fueling more blooms, and thus the blooms have been sustained. Production has appeared to have moved from the benthos to the pelagic, stabilizing at higher levels than in previous decades. The longevity of the blooms thus appears to be due to a


89

combination of initial nutrient supply (possibly from hurricane discharge and/or road material deposition) and autochthonous organic sources combined with restricted flushing and circulation in the central and eastern basins. Indications are that the bloom began to decline in early 2008. Contact Information: Patricia M. Glibert, University of Maryland Center for Environmental Science, Horn Point Laboratory, PO Box 775, Cambridge MD 21613, USA, Phone: 410-221-8422, Email: [email protected]


90

WCA 3 Decompartmentalization and Sheetflow Enhancement Project Implications to Florida Bay Brooke Hall1, Beth Marlowe2, Sue Wilcox2 and Tom St. Clair3

1Parsons, Everglades Partners Joint Venture, Jacksonville, FL, USA 2United States Army Corps of Engineers, Jacksonville, FL, USA 3PBS&J, Everglades Partners Joint Venture, Jacksonville, FL, USA

The Water Conservation Area 3 (WCA 3) Decompartmentalization and Sheetflow Enhancement Project (“Decomp”) is an essential project for the overall success of the Comprehensive Everglades Restoration Plan (CERP). Decomp is widely viewed as the ‘heart’ of Everglades restoration. The purpose of the Decomp project is to restore the ridge and slough habitat within WCA 3 allowing for a more natural sheetflow of freshwater into Everglades National Park (ENP), thus restoring the southern mangrove ecotone and the eastern/central Florida Bay. The Decomp project will be achieved through phased implementation. Initial phases of Decomp will backfill the Miami Canal, provide any necessary conveyance in the North New River, and build upon the Modified Water Deliveries Project (MWD), providing ecological and hydrological connectivity between WCA 3 and ENP. Once the connection to ENP has been restored Decomp will modify the eastern section of Tamiami Trail in concert with degrading the L-29 levee and canal, and additional S-345s to increase the discharge capacity on the L-67 A. Subsequent phases of Decomp will address the features to complete the removal of impediments to flow within WCA 3. This poster will discuss the Decomp project goals and objectives, project components, the phased implementation approach, project schedule milestones, and the proposed adaptive management plan for project implementation. Additionally, the anticipated benefits to Florida Bay recovery and sustainability will be highlighted. Contact Information: Brooke Hall, Parsons, Everglades Partners Joint Venture, 701 San Marco Blvd Suite 1201, Jacksonville, Fl 32207, USA, Phone: 904-232-3443, Fax: 904-232-1056, Email: [email protected]


91

Seagrass as Indicators of Ecosystem Change in South Florida Estuaries M. O. Hall1, M. J. Durako2, M. Merello1, D. Berns1, J. Kunzelman1, K. Toth1 and M. Cristman3

1Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL, USA 2University of North Carolina at Wilmington, Wilmington, NC, USA 3Department of Statistics, University of Florida/IFAS, Gainesville, FL, USA

Introduction - Seagrasses are characteristic of shallow coastal waters worldwide, however, few areas contain meadows as extensive as those found in the south Florida region. Seagrass communities provide key ecological services, including organic carbon production, nutrient cycling, sediment stabilization, and enhanced biodiversity. They are not only a highly productive base of the food web, but are also a principal habitat for higher trophic levels. Because seagrasses are perennial organisms living in close proximity to the land/sea interface, they effectively integrate net changes in water quality parameters (e.g. salinity, light availability, nutrient levels) that often exhibit rapid and wide fluctuations when measured directly. For these reasons, changes in seagrass community structure will be used as a central performance measure for assessing the effects of the Comprehensive Everglades Restoration Program (CERP) in the Southern Estuaries Module. The Florida Bay Fisheries Habitat Assessment Program has provided detailed information on Florida Bay seagrass and macroalgal communities since 1995. However, to assess macrophyte changes that may occur in response to CERP implementation, a more spatially comprehensive monitoring program was required. The South Florida Fisheries Habitat Assessment Program (FHAP-SF) was initiated in spring 2005, increasing the geographic scope of FHAP from ten sampling locations in Florida Bay to a total of twenty-two locations extending from the Lostman’s River to Biscayne Bay (Figure 1). The goal of FHAP-SF is to provide information for the spatial assessment and resolution of inter-annual variability in seagrass communities, and to establish a baseline to monitor responses of seagrass communities to water-management alterations associated with CERP activities. FHAP-SF is documenting the status and trends of seagrass distribution, abundance, and reproduction (ecoindicators), as well as providing process-oriented data such as photosynthetic quantum yields and epiphyte loads. Resource managers will be able to use these data to address ecosystem-response issues on a real-time basis, and to weigh alternative restoration options.

Study Design - Regional FHAP-SF sampling is conducted once per year, at the end of the dry season (May-June). Salinity stress on seagrasses is generally highest at this time, and this is the period when the dominant seagrass of the region, Thalassia testudinum exhibits maximum leaf biomass, increasing our ability to detect changes in cover. Stations are determined using a systematic-random sampling design, and the abundance of seagrass and macroalgal species is visually estimated at approximately 660 stations (30 stations/location) using a modified Braun-Blanquet procedure. At sites where

Rankin Lake

Figure 1. FHAP-SF sampling polygons. Locations monitored since 1995 are labeled in black; Locations monitored since 2005 are labeled in red. Permanent transect locations are indicated by the red dots.

Lostman’s River

Oyster Bay Whitewater Bay

North Biscayne Bay

Port of Miami

North Black Point

Turkey Point

Card Sound

Barnes Sound Manatee Bay

Duck Key Blackwater Sound

Coot Bay

Eagle Key Basin

Crane Key Basin

Calusa Key Basin

Rabbit Key Basin

Johnson Key Basin

Twin Key Basin

Whipray Basin

Madeira Bay

Florida Mainland

Atlantic Ocean

Gulf of Mexico

Florida Bay


92

T. testudinum is present, short-shoots are collected to determine leaf epiphyte biomass, and seagrass morphometric data. Quantum yields and photosynthetic efficiencies are also measured for T. testudinum using pulse-amplitude modulated (PAM) fluorescence. In addition to the annual regional sampling, a more intensive sampling effort is undertaken twice a year (May and October) at 15 permanent transects within Florida Bay (Figure 1). These transects are located adjacent to long-term Southeast Environmental Research Center water quality monitoring stations. Seagrass cover/abundance is assessed using Braun-Blanquet analysis and short-shoot counts. In addition, cores are collected to determine seagrass standing crop and below-ground biomass. Besides increasing our ability to statistically assess seagrass change with respect to CERP implementation, quantitative seagrass biomass data (rather than indirect estimates from regression relationships based on limited data) at specific locations is needed for seagrass model refinement. Results - There was little change in macrophyte distribution and abundance within the twenty-two FHAP-SF sampling locations between 2005 and 2007, however there were substantial changes between 1995 and 2007 within several of the ten, long-term Florida Bay sampling locations (e.g. Johnson Key Basin; Figure 2). These changes were most apparent in western Florida Bay, which was affected by the widespread die-off of Thalassia testudinum in the late 1980’s, and persistent turbidity from algal blooms and sediment resuspension in the early to mid -1990’s. Spatial and temporal patterns of change in western Florida Bay seagrass communities corresponded to changing water quality conditions during the same period (Figure 3).

Lessons Learned - The ability to statistically detect change from baseline conditions is a crucial component of the CERP Monitoring and Assessment Plan. Results to date suggest that changes in seagrass species composition, distribution, and abundance in the Southern Estuaries can be determined using monitoring data collected by FHAP-SF, and that these trends are consistent with available water quality information. However, the extensive variation in seagrass community structure observed from 1995-2007 in Florida Bay reveals that a decade or more of monitoring will be required to obtain an adequate amount of data to detect and interpret ecosystem change related to CERP activities. Contact Information: Penny Hall, Florida Fish and Wildlife Conservation Commission, Florida Fish and Wildlife Research Institute, St. Petersburg, FL 33701, Phone: 727-896-8626, Email: [email protected]

Johnson Key Basin

Jan-

95

Jan-

96

Jan-

97

Jan-

98

Jan-

99

Jan-

00

Jan-

01

Jan-

02

Jan-

03

Jan-

04

Jan-

05

Jan-

06

Jan-

07

Turb

idity

(NTU

)

0

25

50

75

100

125

Figure 2. Braun-Blanquet Abundance of Thalassia, Halodule, and Syringodium in Johnson Key Basin from 1995 to 2007.

Figure 3. Turbidity levels measured in Johnson Key Basin from 1995 to 2007. Data provided by FIU/SERC Water Quality Monitoring Program.

Johnson Key Basin

19951996

19971998

19992000

20012002

20032004

20052006

2007

Mea

n B

raun

-Bla

nque

t Abu

ndan

ce

0

1

2

3

4ThalassiaHaloduleSyringodium


93

Patterns of Propeller Scarring of Seagrass in Florida Bay: Associations with Physical and Visitor Use Factors and Implications for Natural Resource Management David E. Hallac, Jimi Sadle, Leonard Pearlstine and Fred Herling

Everglades and Dry Tortugas National Parks, South Florida Natural Resources Center, Homestead, FL Everglades National Park (ENP) encompasses approximately 607,000 ha at the southern tip of peninsular Florida. Included within the park boundary are over 200,000 ha of marine environments, including most of Florida Bay. The ENP portion of Florida Bay was designated as submerged wilderness in 1978. Much of Florida Bay supports submerged aquatic vegetation comprised of seagrasses and marine algae of various species. Florida Bay is heavily used by recreational boaters, primarily for recreational fishing. While the primary stressors in Florida Bay are related to watershed management, recreational boat use has also resulted in damage to benthic resources. Identification of propeller scarred seagrass beds has been a critical data need by park managers and the public in the development of the park’s General Management Plan (GMP) and for natural resource management in Florida Bay, ENP. To integrate information on propeller scarred seagrass in the development of the GMP, we analyzed 1:24,000 scale aerial photography of Florida Bay. Analyses resulted in detection of 11,751 individual scars ranging in length from 2.1m to 1,680m and totaling 524,978 m. Higher resolution photography at select locations resulted in substantially more scars being detected; thus, suggesting that results provided a minimum estimate of scarring. Grid-based analysis indicated that scarring densities range from 0.0 to 0.25 m/m2. Analysis of 1999, 2004, and 2006 photography suggests that scarring at three locations in Florida Bay has not fully recovered and has increased in all of the mapped sites since 1999. Analysis of aerial photography indicates that loss of seagrass from a propeller dredged channel has also increased steadily from 1995 to 1999 to 2004. To determine if the GMP could identify management measures that would reduce seagrass scarring, allow for seagrass recovery, and prevent seagrass scarring in relatively pristine areas, we analyzed scarring presence and density with physical and visitor use factors. Management options should focus on the most densely scarred areas in Florida Bay; therefore, the top 10% of scarred areas was used for logistic regression analysis with proximity to physical and visitor use factors. Specifically, we performed regressions of scar density versus water depth, proximity to shorelines, marked and unmarked navigational channels, boating activity, and marine facilities in Flamingo and the Florida Keys. In addition, significant factors were used to model potential for prop scarring throughout Florida Bay. Physical and visitor use factors, as associated with propeller scarring density, are discussed in the context of management strategies that may be considered to meet natural resource management objectives. Contact Information: David E. Hallac, Everglades and Dry Tortugas National Parks, South Florida Natural Resources Center, 950 N. Krome Avenue, Homestead, FL 33030, Phone: 305-224-4239, Fax: 305-224-4147, Email: [email protected]


94

Effects of Fertilization and Herbivory on Seagrass Community Structure in Florida Bay Zayda Halun and James W. Fourqurean

Department of Biological Sciences and Southeast Environmental Resource Center, Florida International University, Miami, FL

The importance of resource supply and disturbance in driving competitive interactions among species has been an important but contentious issue within ecology. These variables exhibit different effects on species competition when manipulated in isolation but interact when manipulated together. We tested the effects of nutrient addition and simulated grazing on the competitive performance of primary producers in a seagrass bed in South Florida. One square meter experimental plots were established in a mixed seagrass meadow in August 2007. The experiment is a 3 x 3 factorial experiment: 3 fertility treatments (control, med NP (0.39 g N m-2 day-1, 0.06 g P m-2 day-1) and high NP(0.77 g N m-2 day-1, 0.12 g P m-2 day-1) x 3 herbivory levels (0, 25% and 50 % biomass removal (SH)) x 3 replicates for each treatment = 45 plots). Nutrient additions and simulated grazing were done every two months. The percent cover of all primary producers per square meter was measured using a modified Braun-Blanquet method. Seagrass shoots were collected and analyzed for CNP content. Initial results suggest that a) nutrient enrichment enhanced the growth of Thalassia testudinum and Syringodium filiforme, b) grazing reduced the cover of T. testudinum and S. filiforme but increased the cover of Halodule wrightii and c) the combination of enrichment and grazing increased S. filiforme and H. wrightti cover. Contact Information: Zayda Halun, Department of Biological Sciences, Florida International University, Miami, Fl 33199, USA, Phone: 305-348-1556, Fax: 305-348-1986, Email: [email protected]


95

Coupled Hydrodynamic and Water Quality Modeling of Florida Bay John M. Hamrick1 and Zhen-Gang Ji2

1Tetra Tech, Inc., Fairfax, VA 2Applied Environmental Engineering, LLC, Naples, FL

This presentation summarizes the current status in development of a coupled hydrodynamic and water quality model of Florida Bay focusing on the water quality model component. The overall EFDC based modeling framework and results of the hydrodynamic model component calibration (Tetra Tech, 2006) are reviewed. The formulation and configuration of the water quality model for a seven year calibration simulation period spanning 1996-2002, are discussed including selection of model state variables, development of boundary conditions and land based nutrient loads, and preliminary estimation of model reaction parameters. The embedded sea grass sub-model is also discussed. Results of the seven year water quality model simulation are presented for specific regions of the bay and compared with previous modeling efforts. Water quality reaction parameter adjustments leading these results are discussed. Quantitative measures for evaluation of model performance are reviewed. Performance measures are presented and compared with those for other major water quality modeling studies. Future directions for improving model performance are suggested. Reference: Tetra Tech, 2006. Development of a Florida Bay and Florida Keys hydrodynamic and water quality model:

Hydrodynamic model calibration. a report to: South Florida Water Management District, 128 pp.

Contact Information: John M. Hamrick, Tetra Tech, Inc., 10306 Eaton Place, Fairfax, VA 22030, Phone: 703-385-6000, Fax: 703-385-6007, Email: [email protected]


96

Spatial and Temporal Shifts in Planktonic Phosphorus Limitation in Florida Bay from 2002 to 2007 Cynthia A. Heil1, Patricia M. Glibert2, Sue Murasko3, Jeff Alexander2, Merrie Beth Neely2, Ana Hoare3 and Chris Madden4

1Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, St. Petersburg, FL 2University of Maryland Center for Environmental Science, Horn Point Laboratory, Cambridge MD 3College of Marine Science, University of South Florida, St. Petersburg, FL 4Coastal Ecosystems Division, South Florida Water Management District, West Palm Beach, FL

Within Florida Bay, both nitrogen and phosphorus play an important role in plankton dynamics, and the generalization that N limitation occurs in the western Bay and P limitation of biomass in the eastern Bay has been widely accepted. We examined how both inorganic and organic phosphorus (P) regulates phytoplankton communities in Florida Bay from 2002-2007. Strong P limitation, as evident from changes in chlorophyll a biomass in 48 hr nutrient enrichment assays and by the presence of both detectable and inducible alkaline phosphatase activity (APA), was present not only in eastern Bay stations from 2002-2006 but at ~50% of assays with Little Madiera Bay and Rankin Bight populations and at least once in western Bay populations between 2002 and 2007. All Bay algal populations were able to store P within 24 hrs of additions of either 2.0 uM PO4 or DOP (as glycerol-phosphate), however, eastern and northern Bay populations achieved higher P: Chl ratios (~20) than did western Bay populations (~8). Eastern Bay populations utilized this stored P and depleted it within 48 hrs, suggesting that a gradation in severity of P limitation exists. The presence of significant APA activity in the eastern Bay, with activity in the dissolved (<0.2 μm) fraction often equal or greater than particle associated activity, as well as a significant correlation between response (as increases in chlorophyll a) with humic acid and P additions in the eastern Bay also suggests that abiotic and/or geochemical regulation of P supply to algae is more significant in the eastern Bay. The occurrence of a large, persistent Synechococcus spp. bloom in the northeastern Bay in fall of 2005 shifted the pattern of response in enrichment bioassays from P dominated (both inorganic and organic P) to a combined DON plus DOP enhancement, suggesting that this abiotic control of nutrient limitation had shifted to a biotic control, with a dominant bloom organism capable of utilizing both inorganic and organic N and P forms exploiting a different nutrient niche than previously present in the eastern Bay. Contact Information: Cynthia Heil, Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, 100 Eighth Ave. S., St. Petersburg, FL 33701, Phone: 727-896-8626 x 1524, Fax: 727-550-4222, Email: [email protected]


97

Phosphorus Availability and Salinity Control Productivity and Demography of the Seagrass Thalassia testudinum in Florida Bay Darrell A. Herbert1 and James W. Fourqurean1, 2

1Department of Biological Sciences and Southeast Environmental Research Center, Florida International University, Miami, FL

2Fairchild Tropical Botanic Garden, Coral Gables, FL Biomass, net primary productivity (NPP), foliar elemental content, and demography of Thalassia testudinum was monitored in populations from five sites across Florida Bay beginning in January 2001. Sites were selected to represent a gradient of phosphorus (P) availability and salinity variability across the bay. Aboveground biomass and NPP of T. testudinum were determined 5 - 6 times annually. Shoot demography, belowground biomass, and belowground NPP were assessed from a single destructive harvest at each site and shoot cohorts were estimated from leaf scars counts, multiplied by site-specific leaf production rates (leaves shoot-1 year-1). Biomass, relative growth rate (RGR), and NPP were positively correlated with P availability (Figure 1). Additionally, a positive correlation between P availability and the ratio of photosynthetic to non-photosynthetic biomass suggests that T. testudinum increases allocations to aboveground biomass as P availability increases. Population turnover rates increased with P availability, evident in positive correlations of recruitment and mortality rates with P availability and areal leaf mass (Figure 2). Departures from seasonally modeled estimates of RGR were found to be influenced by salinity, which depressed RGR when below 20 psu (Figure 3). Freshwater management in the headwaters of Florida Bay will alter salinity and nutrient climates. It is becoming clear that such changes will affect T. testudinum, with likely feedbacks on ecosystem structure, function, and habitat quality.

Contact Information: Darrell Herbert, Florida International University, Southeast Environmental Research Center and Biology, 12000 SW 8th Street, Miami, FL 33199, Phone: 305-348-7317, Email: [email protected]

Cur

rent

yea

rre

crui

tmen

t (yr

-1)

0.2

0.4

0.6

0.8

1.0

1.2

r2 = 0.93p < 0.01

Leaf mass (g m-2)

10 20 30 40 50

Mor

talit

y (y

r-1)

0.2

0.4

0.6

0.8

1.0

r2 = 0.75p = 0.06

Salinity (psu)< 20 25 35 >40

Res

idua

l Rel

ativ

e G

row

thR

ate

(mg

g-1da

y-1)

-6

-4

-2

0

2

4

6

a a

bab

14 3

1115

Foliar P concentration (%)

0.05 0.10 0.15

RG

R (m

g g-1

day-1

)

2

4

6

8

NP

P (g

m-2da

y-1)

0.3

0.6

0.9

1.2

r2 = 0.91p = 0.01

r2 = 0.94p < 0.01

Figure 1. Foliar P versus net primary productivity, and relative growth rate (including belowground components).

Figure 2. Mortality and recruitment versus leaf mass. Whiskers represent 95% confidence intervals

Figure 3. The residual difference between measured aboveground RGR and predicted aboveground RGR at sites where salinity fluctuated widely. Bars below the zero reference indicate depressed RGR. Whiskers represent standard error. Letters indicate Duncan-Waller groupings. Values represent the sample size.


98

Remote Sensing Of Water Quality Index in Florida Bay and Florida Keys: Current Status and Challenge C. Hu,1 J. Cannizzaro,1 F. Muller-Karger,2 J. Hendee3, E. Johns3, L. Gramer,4 C. Kelble,4 and N. Melo4

1College of Marine Science, Univ. South Florida, St. Petersburg, FL, USA 2School for Marine Science and Technology, Univ Massachusetts Dartmouth, New Bedford, MA 3Atlantic Oceanographic and Meteorological Lab, NOAA, Miami, FL, USA 4Cooperative Institute for Marine and Atmospheric Studies, Univ. Miami, Miami, FL, USA

Satellite remote sensing provides the only means to synoptically and frequently assess the environmental health in Florida Bay and its adjacent water environment. Here we present a current update on the recent progress and challenge in deriving several key water quality parameters to help understand the environmental changes and ecosystem connectivity. These water quality parameters include mainly sea surface temperature (SST) and those derived from satellite ocean color measurements. SST is an important indicator for potential coral bleaching (Goreau and Hayes 1994, Brown 1997). Based on the AVHRR satellite data, NOAA’s Coral Reef Watch (CRW) team developed global HotSpot and Degree Heating Week (DHW) products to monitor potentially massive bleaching events (Strong et al., 2004, www.osdpd.noaa.gov/PSB/EPS/SST/climohot.html). However, these products are designed for the global ocean, and the coarse spatial resolution (50 km per image pixel) makes it difficult to apply to the heterogeneous coastal waters such as Florida Bay and Florida Keys. Based on the statistics of cloud cover and seasonal patterns from the AVHRR and MODIS satellite instruments, we have developed SST anomaly and DHW data products at 1-km resolution (Hu et al., in press), with real-time data integrated in NOAA’s Integrated Coral Observing Network (ICON, Hendee et al., in press). Validation results using concurrent (±0.5 hour) data from the SEAKEYS in situ stations showed near-zero bias errors (<0.05oC) in the weekly SST anomaly data between -3 and 3oC, with standard deviations <0.5oC. Because corals can also be under stress or even bleached in unusually cold waters (Saxby et al., 2003), these high-resolution, weekly updated SST products provide valuable information in monitoring and studying this ecologically important variable (imars.usf.edu/merged). For example, using the validated high-resolution SST products, Soto (2006) found that reefs associated with higher SST variability tended to be healthier and more resilient to environmental changes. While satellite SST is a robust data product, deriving ocean color data products has been problematic due to a number of reasons. Fig. 1 shows that chlorophyll-a concentrations derived from satellites deviate from those obtained in situ, especially for Florida Bay. The deviation becomes larger at lower concentrations, mainly due to the interference of the shallow bottom. However, the data products can be used in two ways at present. First, they serve as color tracers to document water movement and connectivity (Fig. 2a, also see Hu and Muller-Karger, 2008). Then, because MODIS fluorescence line height (FLH, mW cm-2 m-1 sr-1) is nearly immune to the interference of other color constituents, FLH serves as a reliable indicator of phytoplankton bloom (Hu et al., 2005). Fig. 2b shows an episodic bloom north of the lower Keys, after which macro algae were found on the benthos. The bloom apparently initiated from Florida Bay, according to time series of satellite imagery. Similar time-series analysis at a given location can also be used to indicate extreme conditions, for example black water or white water events.


99

Fig. 1. Comparison between chlorophyll-a concentrations determined from in situ measurements (bimonthly cruises from NOAA/AOML South Florida Program 2002-2006, and monthly to bimonthly cruises from NOAA/AOML FL Bay Program 2002 – 2008. Note the poor performance of MODIS/Aqua for the Florida Bay (right panel).

Fig. 2. Examples of satellite imagery showing connectivity between Florida Bay and Florida Keys, and the potential effect of such connectivity. (a) MODIS Chl image (11/23/2005) showing several eddies and the bay water intrusion through the channels to FKNMS. (b) MODIS FLH image showing an episodic bloom in “Rock Pile” (black cross).

An effort is underway to correct the artifacts in the satellite ocean color data products, and an automatic system for color anomaly detection and its integration with ICON, similar to that for SST anomaly, is also being developed under the support of the US NOAA and NASA. References Brown, B.E. (1997). Coral bleaching: causes and consequences. Coral Reefs 16:S129-S138. Goreau, T.J. and R.L. Hayes (1994). Coral bleaching and ocean ‘hot spots’. Am Bio 23: 176-180. Hendee J. C. et al. (2007) The Integrated Coral Observing Network: Sensor solutions for sensitive sites. Third Intl

Conf on Intelligent Sensors, Sensor Networks and Information, 669-673.. Hu, C., et al. (2005). Red tide detection and tracing using MODIS fluorescence data: A regional example in SW

Florida coastal waters. Remote Sens. Environ., 97:311-321. Hu, C., and F. E. Muller-Karger (2008). On the connectivity and “black water” phenomena near the FKNMS: A

remote sensing perspective. In: Connectivity – Science, People and Policy in the FKNMS (B. D. Keller and F. C. Wilmot eds, 263pp). 47-55.


100

Hu et al. (in press). Building an automated integrated observing system to detect sea surface temperature anomaly events in the Florida Keys. IEEE TGRS.

Saxby, T., et al. (2003). Photosynthetic responses of the coral Montipora digitata to cold temperature stress. Mar. Ecol.-Prog. Ser., 248:85-97.

Soto, I. (2006). Environmental variability in the Florida Keys: Impacts on coral reef health. M.S. thesis, USF, 2006. Strong, A. E., et al. (2004). Coral reef watch 2002. Bulletin of Marine Science, 75:259-268.

Contact Information: Chuanmin Hu, University of South Florida, College of Marine Science, 140 Seventh Avenue, South, St. Petersburg, FL 33701, Phone: 727-553-3987, Fax: 727-553-1103, Email: [email protected]


101

Minimum Inflow Analyses in Adjacent Systems: Why Are They Different? Melody J. Hunt

Water Supply Department, South Florida Water Management District, West Palm Beach, FL, USA The importance of establishing minimum inflow criteria for coastal areas is becoming recognized world-wide. The majority of coastal inflow criteria that have been developed to date are for riverine systems. In south Florida, most criteria have been based on the presence of an oligohaline reach or freshwater floodplain, where a salinity sensitive species or community is established. Application of inflow criteria is very limited in non- riverine wetland- dominated systems such as Florida Bay and Biscayne Bay, with diffusely distributed inflow sources. In 2006 a minimum flow and level was established for northeastern Florida Bay. This inflow criteria applied a resource-based approach using the SAV indicator species Ruppia maritima (widgeon grass) located in ponds within the Everglades/Florida Bay transition zone, which remains a relatively natural area. Similar to previous efforts in riverine systems, impacts to this resource are defined in terms of a freshwater inflow regime and corresponding salinity levels required for survival of the freshwater habitat. During periods that illustrate impacts in the transition zone, resulting salinity conditions in northeastern Florida Bay were evaluated. The inferred effects on the seagrass community and its inhabitants are described under these low flow conditions to assess the impacts on the downstream Florida Bay ecosystem. Although adjacent and sharing common physical-biological attributes, the Biscayne Bay ecosystem differs from Florida Bay because the adjacent transition zone has been highly altered. The once wetland dominated watershed of Biscayne Bay now includes: the City of Miami and surrounding urban areas; agricultural areas; mining; a nuclear power facility; and other modified land uses. The overland flow component from natural wetlands, that once connected the natural tidal creeks to regional freshwater sources, no longer exists for Biscayne Bay due to development in the watershed. Although inflow criteria have been established in modified riverine systems in South Florida, and adjacent Florida Bay, this land–based difference makes it difficult to apply previously used approaches in Biscayne Bay. Contact Information: Melody J. Hunt, MC 4350,Water Supply Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL, 33406, Phone: 561-682-2736, Email: [email protected]


102

Characterizing the Dynamics of Dissolved Organic Matter in the Florida Coastal Everglades Rudolf Jaffé1,2, M. Chen1,2 , Y. Yamashita1,2, N. Maie1,2, K. Parish1,2, R. M. Price1,3, J. Boyer1 and L. Scinto1,4

1Southeast Environmental Research Center, Florida International University, Miami, FL, USA 2Department of Chemistry and Biochemistry, Florida International University, Miami, FL, USA 3Department of Earth Science, Florida International University, Miami, FL, USA 4Department of Environmental Studies, Florida International University, Miami, FL, USA

Dissolved organic matter (DOM) dynamics in wetlands and estuaries are complex and often difficult to assess using traditional geochemical approaches. It has become clear that quantitative measurements (DOC) alone do not properly allow for assessing the multitude of sources (e.g. emergent and submerged vegetations, soil/sediments, groundwater, and rainwater) and the various diagenetic processes (e.g. photodegradation, biodegradation) that can alter the DOM characteristics in aquatic ecosystems. In this study, we incorporate bulk DOC measurement with several spectroscopic techniques, including UV-Vis and fluorescence to characterize the sources and distribution of DOM across the greater Everglades landscape. Specifically, Emission Excitation Matrices fluorescence (EEM) coupled with Parallel Factor Analysis (PARAFAC) were used successfully to understand the dynamics of DOM in the Everglades landscape ranging from the Water Conservation Areas, through Everglades National Park, to Florida Bay and the Florida Keys. Additionally, DOM in surface and groundwater, dominant vegetation leachates (including periphyton, seagrass, and senescent leaves of sawgrass, spikerush and mangroves) and soil leachates were characterized using EEM-PARAFAC and potential degradation processes were assessed through bio-and photo-degradation studies. Fluorescence based EEM-PARAFAC analyses revealed DOM compositional differences both on spatial and temporal scales. As such increased microbial source loadings in some estuarine areas and Florida Bay during the wet season and during high primary productivity were observed. A clear trend from soil dominated to microbially enhanced DOM sources was observed along a sampling grid ranging from the northern to the southern Everglades. Compositional differences between waters from the peat based Shark River Slough and the marl-based Taylor Slough as well as clear differences between surface and ground water DOM were also observed. Florida Bay could be subdivided into four distinct zones based on DOM composition, and seasonal variations were controlled by primary productivity patterns and hydrologically controlled discharge from the Everglades. For the Florida Keys region, DOM changes with distance from shore were observed as was the influence of Florida Bay waters in the Keys. Differences between surface waters DOM and that in groundwater from both the Everglades and Florida Bay were also observed applying EEM-PARAFAC. Photo- and bio-degradation of plant leachates readily showed that the combination of both processes was most effective in promoting DOM compositions similar to those in natural surface water of the Florida Coastal Everglades. The data generated in this study will make a significant contribution to a better understanding of subtropical wetland and estuarine DOM characterization and its environmental dynamics, biogeochemical carbon cycling processes, and potential relationships to environmental restoration and global climate change issues. Contact Information: Dr. Rudolf Jaffé, Southeast Environmental Research Center, Florida International University, Miami, FL. 33199, USA, Phone: 305-348-2456, Fax: 305-348-4096, E-mail: [email protected]


103

Biscayne Bay Salinity Monitoring Program Sarah Bellmund1, Herve Jobert2, Greg Garis1, Steve Blair3 and Amy Renshaw4

1Biscayne National Park, Homestead, FL. USA 2Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Miami, FL, USA 3Miami-Dade County Department of Environmental Resources Management, Miami, FL, USA 4South Florida Natural Resources Center, Everglades National Park, Homestead, FL, USA

Biscayne National Park administers the Biscayne Bay salinity monitoring program in conjunction with Miami-Dade County Department of Resources Management (DERM). This is a portion of the Comprehensive Everglades Restoration Plan (CERP) Monitoring and Assessment Plan (MAP) to provide information necessary to assess the effects of the CERP program on Biscayne Bay. This program was developed with the United States Army Corp of Engineers (USACE), the South Florida Water Management District (SFWMD), Miami-Dade County, National Marine Fisheries Service (NMFS), and Everglades National Park. The goal of this program is to better understand Hydrodynamic patterns in Biscayne Bay and the salinity regime as it relates to organisms. It is important to understand how the bay responds to natural and human induced operations. This will aid in understanding the Bay’s response to CERP. There are 34 monitoring sites instrumented with YSI 6600 data sondes that continuously monitor temperature, depth, and conductivity. Sites were chosen by taking into consideration the contributions of navigational channels, canals, inlets, and freshwater inflow. Ten of these sites have been equipped with buoys that allow meters to take data immediately below the waters surface, while at the same site a meter is logging data on the bottom. The northernmost site of the Biscayne National Park network is located south of Snapper Creek canal and sites are located as far south as Barnes Sound and Manatee Bay. Especially important, are the near-shore areas on the west side of the bay that have highly altered canal inflows which experiences hyper-salinity alternating with extreme pulses of freshwater canal inflow. These operations result in conditions in the bay that are detrimental to the fragile ecosystems of Biscayne Bay.

2007 Biscayne Bay dry season vs. wet season. Contact Information: Herve Jobert, Biscayne National Park. 9700 S.W. 328th St., Homestead, Florida. 33033, Phone: (305) 230-1144, Email: [email protected]


104

Surface Salinity Variability of South Florida Coastal and Estuarine Waters from Gridded Shipboard Observations, 1995 - 2008 Elizabeth M. Johns1, Thomas N. Lee3, Christopher R. Kelble2, Ryan H. Smith1, Nelson Melo2, Peter B. Ortner2 and Vassiliki H. Kourafalou3

1Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL, USA

2Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL, USA 3Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA

The coastal ecosystems of south Florida are under the influence of physical forcing processes including currents and tides, wind forcing, precipitation/evaporation patterns, and direct freshwater inputs from surface run-off, on a wide range of spatial and temporal scales. Superimposed on this highly variable and dynamic coastal marine system are the past and present effects of water management practices in south Florida as well as the future changes in fresh water deliveries to the estuaries and coastal marine waters which are to be expected as a result of the Comprehensive Everglades Restoration Plan (CERP). Each of these natural and anthropogenic physical forcing processes is manifested in some way in the surface salinity field, which can be used to examine the mechanisms by which the physical forcing processes act on the system and to assess the degree of connectivity between coastal and estuarine ecosystems. Ultimately, understanding how the system behaves under the spatially and temporally varying physical forcing to which it is subjected will aid in the development of improved numerical models and better predictive capabilities for science-based resource management. The surface salinity data used in this study were obtained from a series of cruises conducted collaboratively between NOAA's Atlantic Oceanographic and Meteorological Laboratory and the University of Miami's Rosenstiel School of Marine and Atmospheric Science, from 1995 to the present. Thermosalinograph data from cruises to the larger coastal region were combined with similar data from shallow water cruises to Florida Bay and Biscayne Bay conducted as closely in time as logistically possible, often concurrently. Salinity data were objectively gridded using krigging methodology to a .02 degree latitude/longitude grid for the Bays, and a .05 degree latitude/longitude grid for the larger scale coastal surveys. The gridded data were used to generate an overall mean salinity field, and annual means, seasonal means, anomaly maps, and time series for particular locations and/or regions. Quantitative statistical methods were used to analyze the complex spatial and temporal patterns observed in the gridded data. The results of this analysis are used herein to identify key locations exhibiting relatively high variability, key time periods such as low (high) salinity events related to El Nino (La Nina) patterns, and episodic events causing sudden extrema in the precipitation/evaporation balance such as the passage of tropical cyclones. The transient presence in the study area of waters from remote sources such as the Mississippi River outflow is also examined in the surface salinity record. Comparisons with satellite remote sensing data and numerical model results are shown for selected case studies. Satellite-tracked surface drifter trajectories, and wind and current data from fixed moored instruments, are also used to aid in the analysis of the surface salinity data and to demonstrate the varying circulation patterns and the degree of connectivity between the sub-regional ecosystems of south Florida. Contact Information: Elizabeth M. Johns, Physical Oceanography Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, 4301 Rickenbacker Causeway, Miami, FL, 33146, USA, Phone: 305-361-4360, Fax: 305-361-4412, Email: [email protected]


105

Factors Affecting Seagrass and Mangrove Fauna Adjacent to the South Biscayne Bay Shoreline Darlene R. Johnson1, Joan A. Browder2, Joseph E. Serafy2, Michael B. Robblee3, Thomas L. Jackson2, Gladys Liehr1, Eric Buck1 and Brian Teare1

1CIMAS/RSMAS, University of Miami, Miami, FL, USA 2Southeast Fisheries Science Center, National Marine Fisheries Service/ NOAA, Miami, FL, USA 3United States Geological Survey, Center for Water and Restoration Studies, Everglades National Park Field

Station The mangrove fringe habitat (principally red mangrove, Rhizophora mangle), harbors many fishes that feed on the epifauna occupying seagrass, macroalgae, sponge, and other habitats of adjacent shallow-water flats. The research objectives of the present study were to: (1) develop a baseline characterization of the epifauna of the very shallow open-water area immediately adjacent to the South Biscayne Bay mangrove-covered shoreline, including community composition and species density; (2) relate community metrics and species density to salinity regime; (3) relate species occurrence, concentration, and density to habitat characteristics measured in association with faunal sampling, and (4) examine potential functional relationships between open-water seagrass epifauna and shoreline mangrove fishes such as gray snapper, schoolmaster snapper, and great barracuda, and the possible influence of salinity regime on these relationships. The focus of this project was to develop information on interrelationships as a foundation for detecting early ecological changes brought about by changes in hydrology. Examining potential relationships between predator and prey and between epibenthic prey and benthic habitat may be the key to understanding ecological relationships with salinity for both faunal groups. This project was started in 2006 as part of the Minimum Flows and Levels Program of the South Florida Water Management District (SFWMD). Work in subsequent years, 2007 and 2008, was part of RECOVER’s Monitoring and Assessment Plan of the Comprehensive Everglades Restoration Project (CERP). CERP and other water management actions will alter salinity patterns first and most profoundly in the very shallow water in close proximity to shore. While water depths in this area are similar, the bottom cover varies from relatively dense Thalassia to scattered attached algae and sponges, and salinities range from near zero to greater than 40 psu, providing the opportunity to explore variation in epifaunal diversity and abundance in relation to habitat and salinity variation. Multi-regression models were developed for seagrass and mangrove fauna adjacent to the South Biscayne Bay shoreline. Data were collected using throw-trap (seagrass habitat) and visual census (mangrove habitat) methods. Sampling sites of the two habitats were located in close proximity, and sampling was conducted at the same time of year by the two methods in order to better explore the relationship between the two habitats. Model variables included physical factors such as salinity, temperature, depth, and dissolved oxygen and biological factors such submergent vegetation, predators, and prey. Wet and dry seasons are being analyzed separately. Model results will be presented. Fourteen significant dry season models were developed. These were for the following species: Callinectes sapidus, Carideans, Farfantepenaeus duorarum, Floridichthys carpio, Gobiosoma robustum, Lucania parva, Microgobius gulosus, and Opsanus beta from the seagrass habitat, and


106

Floridichthys carpio, Gerres cinereus, Eucinostomus spp., Lutjanus griseus, Sphyraena barracuda, and Sphoerodes testudineus from the mangrove habitat. Wet season seagrass models were developed for the same group of species as the dry season. The mangrove models included the above species plus six additional species: Lutjanus apodus, Haemulon sciurus, Haemulon parra, Lagodon rhomboides, Abudefduf saxalis, and Strongylura notata. Proposed response webs for the dry and wet seasons, as derived from our statistical models are presented. Contact Information: Darlene Johnson, SEFRC/NMFS, 75 Virginia Beach Drive, Miami, Florida 33149, USA, Phone: 305-361-4490, Email: [email protected]


107

Contribution of Mangrove Nursery Habitats to Replenishment of Adult Reef Fish Populations in Southern Florida David. L. Jones1, John F. Walter2 and Joseph E. Serafy2

1Cooperative Institute for Marine & Atmospheric Studies, University of Miami–Rosenstiel School, Miami, FL, USA

2NOAA Fisheries, Miami, FL, USA Connectivity between mangrove forests and coral reefs, mediated by ontogenetic migrations of reef fishes that use mangroves for juvenile nursery habitat, may be crucial for the replenishment of adult populations on the reef. However, direct evidence of this linkage and an understanding of the influence variability of juveniles within mangrove nurseries has on the dynamics of nearby adult reef fish populations is lacking for many species. Our goal is to establish the nature and extent of the linkage between mangrove and reef habitats by synthesizing two long-term, visual survey-based monitoring efforts of southern Florida populations of fishes from: 1) the inshore mangrove nursery habitats in Biscayne Bay (J. Serafy, Univ. of Miami/NOAA Fisheries) and 2) the adjacent Florida Keys reef tract (J. Bohnsack, NOAA Fisheries). This involves construction of predictive models of recruitment dynamics that incorporate ontogenetic habitat shifts (i.e., mangrove to reef), account for environmental variation, and allow estimation of adult reef fish stock size. Development of an annual, abundance-based index of recruitment, based on the juvenile survey data, will allow identification of essential fish habitat and provide information necessary for adequate stock assessment and proper management of the fishery. Based on their presence and abundance in both the mangrove and reef surveys, ten target species from seven families were identified as having potential to exhibit ontogenetic shifts between the two habitats (i.e., Abudefduf saxatilis, Gerres cinereus, Haemulon flavolineatum, H. parra, H. sciurus, Lagodon rhomboides, Lutjanus apodus, L. griseus, Scarus guacamaia, Sphyraena barracuda). Length and abundance data for these species collected during 981 mangrove survey transects conducted in Biscayne Bay over nearly a decade (1999–2007) form the basis of the present work. These data were partitioned according to spatial (habitat, lat/long) and temporal (year, season) treatments and redundancy analysis (RDA) was used to establish the influence of these along with several other environmental variables (i.e., salinity, temperature, depth, dissolved oxygen, freshwater discharge) on the distribution and abundance of juvenile mangrove fishes. Habitat had the greatest influence on the distribution and abundance of these fishes. Most (80%) of the target species showed an affinity for Leeward Key sites, which were farther from the influence of freshwater canal discharge than sites along the Mainland and closer to offshore waters where the adults reside and larval input originates. Large-scale spatial trends in utilization of mangrove nursery sites within Biscayne Bay further highlight the importance of Leeward Key mangroves in providing essential nursery habitat as 90% of the target species immature stages were significantly more abundant here than along the Mainland. Juveniles and/or subadults of all target species showed greatest abundances in the mangroves during the wet season, ostensibly coincident with seasonal peaks in reproduction and the subsequent timing of habitat shifts made by early juveniles that initially settled in seagrass beds. Life history stage data provide evidence suggesting habitat shifts from the mangroves occur between the juvenile and adult stages in nine of the 10 species examined. Patterns of habitat utilization among closely related species indicate alternative life history strategies exist to minimize competition. For example, French grunt (H. flavolineatum) and schoolmaster snapper (L. apodus) inhabit the mangroves at earlier stages and


108

for shorter durations than their generic counterparts, bluestriped grunt (H. sciurus) and gray snapper (L. griseus). Contact Information: David L. Jones, Cooperative Institute for Marine and Atmospheric Studies, University of Miami - Rosenstiel School, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA, Phone: 786-374-5295, Email: [email protected]


109

Juvenile Spotted Seatrout Power Analysis and Monitoring for Florida Bay Christopher R. Kelble1, Clay E. Porch2, Allyn B. Powell3, Mike Lacroix3, Michael Greene3 and Joan Browder2

1Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA

2NOAA/NMFS Southeast Fisheries Science Center, Miami, FL, USA 3NOAA Center for Coastal Fisheries and Habitat Research, Beaufort, NC USA

Spotted seatrout, Cynoscion nebulosus, are an indicator of the overall health of Florida Bay, in part because they spend their entire life history within the Bay and their abundance varies in response to ecological changes. Specifically, the distribution of juvenile spotted seatrout has been observed to vary in response to salinity conditions (Thayer et al., 1999), making them an ideal indicator to assess the Bay’s response to water management changes in the Comprehensive Everglades Restoration Plan (CERP). In the 1980's when hypersaline conditions were persistent in north-central Florida Bay, seatrout distributions were mainly limited to the western Bay. During 1994-2001, when hypersaline conditions in the north-central Bay occurred only seasonally, the distribution of spotted seatrout juveniles expanded into this part of the Bay. In the future as restoration proceeds, salinity patterns of Florida Bay are expected to change in response to changes in the quantity, quality, timing, and distribution of freshwater runoff. Salinity changes have the potential to both positively and negatively affect the abundance of juvenile spotted seatrout. Increased freshwater flows can alleviate hypersaline conditions that could result in an expansion of the spatial distribution of juvenile spotted seatrout. However, when salinities become too low the planktonic eggs of spotted seatrout sink to the bottom and are not viable. This RECOVER Monitoring and Assessment (MAP) project began with a power analysis to guide development of the sampling regime. The power analysis was conducted to ensure that monitoring activities were capable of detecting changes in the seatrout population by optimizing the number and distribution of sampling stations. A total of 112 stations distributed in a stratified manner between four sub-regions (Crocodile Dragover, Rankin, Whipray and West) form the basis for the sampling regime. Based on the original power analysis, 60 of these stations are selected randomly for sampling each month during the peak times of juvenile spotted seatrout abundance (June through November) for a total of 360 samples per year. The highest densities of juvenile spotted seatrout have been observed in the West sub-region (2.03 m-3), followed by Whipray (1.79 m-3), Rankin (0.98 m-3), and Crocodile Dragover (0.20 m-

3). There is significant interannual variability in these densities, and variability differs between sub-regions, indicating the importance of sub-regional scale processes in determining the abundance of juvenile spotted seatrout. However, a significant increase of juvenile spotted seatrout was observed in Rankin, Whipray, and Crocodile Dragover following the passage of three hurricanes in 2005, signifying that larger scale forcing events may also influence the distribution. An obvious effect of the hurricanes was a breakdown in the hypersaline conditions previously persisting in the north-central bay.


110

Understanding and quantifying the relationship between salinity and juvenile spotted seatrout is necessary to develop quantifiable, testable hypotheses regarding the effect of CERP. In all sub-regions except the west, the data show a significant decline in the mean annual frequency of occurrence of juvenile spotted seatrout with increasing mean annual salinity (Fig. 1). The lack of a response in the west is likely due to its relatively stable salinity regime. Interestingly, there was no consistent relationship between mean annual salinity and mean annual concentration.

Figure 1. The relationship between the frequency of occurrence of spotted seatrout juveniles and salinity by sub-region in Florida Bay. The original power analysis was parameterized with data collected prior to this MAP project. The prior data had been collected sporadically, and the sampling distribution was not systematically designed to capture sub-regional variability. A sampling design that is continuous and systematically distributed across sub-regions was established based on that original power analysis. Now, the power analysis has been updated with 4 years of the new systematic data. Results were used to optimize the sampling protocol in terms of both the spatial distribution of samples and the total number of samples collected. Hypotheses about changes in juvenile spotted seatrout abundance in response to future CERP implementation and other factors will be formed from the optimized sampling scheme, juvenile spotted seatrout population dynamics, and a general linear model. Contact Information: Christopher R. Kelble, Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA, Phone: 305-361-4330, Fax: 305-361-4447, Email: [email protected]


111

Marine and Estuarine Goal Setting for South Florida (MARES) Peter B. Ortner1, Carol L. Mitchell2, Joseph N. Boyer3 and Christopher R. Kelble1


2Southeast Environmental Research Center, Florida International University, Miami, FL, USA 3South Florida Natural Resources Center, Everglades National Park, Homestead, FL, USA

Within South Florida’s coastal marine ecosystem there are major geographical domains with distinct environmental threats and inherent tradeoffs that, for a variety of reasons, have received insufficient attention within the Comprehensive Everglades Restoration Plan (CERP) and South Florida Ecosystem Restoration (SFER). To reach a much needed consensus with respect to quantitative goals for a sustainable and healthy regional marine ecosystem, we will be holding a series of workshops to bring together a broad range of interested individuals, agencies and institutions. This presentation represents the first official announcement of our intention and solicitation of community interest in participation. Two types of workshops will be held for each of the four domains of interest. The task of the first type will be to produce Conceptual Ecological Models (CEMs) with supporting text and explicit qualitative goals, while that of the second workshop type will be to develop Quantitative Ecosystem Indicators (QEIs). Indicator workshop results will be disseminated and additional input acquired by conducting targeted briefings for resource managers and planners as well as facilitated workshops specifically for stakeholder groups. These facilitated workshops will rely upon a DecisionPlace® suite of tools. This interactive ‘gaming style’ interaction was piloted at the recent Greater Everglades Ecosystem Restoration (GEER) conference and proved useful in engaging audiences as it provides fun and useful interaction to help improve the understanding of the biophysical, social and institutional knowledge. Subsequent, iterative discussions aid in identifying and addressing the ongoing questions, risk and uncertainty that supports truly adaptive and transparent ecosystem management decisions. Indicators and goals will then be further refined as result of the input obtained at these additional briefings and workshops. As technical questions emerge (and they undoubtedly will), smaller non-facilitated meetings will be held to produce supplementary white papers and topical reports. Where possible, follow-up meetings and document production will be conducted “virtually”, via SharePoint®, through the project website and server. The project website would also be used for outreach and education purposes. At the conclusion of the project, both specific recommendations and an overall South Florida coastal ecosystem Report Card will be delivered to the funding agency (NOAA) and the participating Federal and State agencies and non-governmental organizations (NGOs). Contact Information: Christopher R. Kelble, Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA, Phone: 305-361-4330, Fax: 305-361-4447, Email: [email protected]


112

Relationship of Mesozooplankton to Water Quality in Florida Bay Christopher R. Kelble1, Peter B. Ortner1, Gary L. Hitchcock2 and Michael J. Dagg3


2Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA 3Louisiana Universities Marine Consortium, Chauvin, LA, USA

Mesozooplankton occupy a vital link in the pelagic trophic network, providing an energy pathway between primary producers and upper trophic levels and mesozooplankton have been observed to correlate significantly with water quality. Florida Bay has a large degree of spatial and temporal variability in water quality, which is the result of heterogeneity in freshwater sources, minimal exchange between the four major sub-regions, seasonal cycles of rainfall, runoff, and evaporation, and the influence of large-scale phenomena (i.e. tropical cyclones and El Nino). It is against this large degree of variability that changes due to CERP activities must be detected and quantified, especially for salinity which is likely to be the environmental parameter most directly affected by CERP activities. Understanding the relationship between mesozooplankton communities and water quality, particularly salinity, is necessary to formulate quantitative, testable hypotheses as to the potential effect of CERP projects on mesozooplankton community structure and abundance. There is an ongoing long-term research program to study mesozooplankton communities in Florida Bay. Mesozooplankton were collected approximately bi-monthly at 10 stations in Florida Bay from September 1994 to September 2004. Of these 10 stations, a subset of 4 stations with one representative from each of the four Florida Bay sub-regions (west, north-central, northeast, and south) was identified and counted to plankton functional type for the period of record. This data was then analyzed in conjunction with coincidentally collected water quality data to quantify and examine the relationship between mesozooplankton and water quality in Florida Bay. The mesozooplankton communities showed significant differences between sub-regions in all 7 of the dominant plankton functional types (nauplii, Bivalvia, Gastropoda, Oithona, Acartia, Paracalanus, and Harpacticoida). There were also significant differences in the water quality variables which correlated with the mesozooplankton community between sub-regions. For example, in the northeast 5 of the 7 dominant mesozooplankton functional types displayed differences related to TP, but in the north-central TP did not have a relationship with any of the functional types. These differences highlight the influence of small scale processes in structuring the mesozooplankton community. However, all sub-regions had much lower abundances of mesozooplankton in 1996 and 1996 and Tropical Storm Irene that made landfall adjacent to Florida Bay resulted in a unique mesozooplankton community assemblage. This indicates that larger scale, bay-wide processes are also important in structuring the mesozooplankton community. The water quality parameter which showed the highest correlation with mesozooplankton community structure was salinity which was correlated with 6 of the 7 dominant mesozooplankton functional types. This is further evidenced via a principal components analysis where 5 of the 7 mesozooplankton functional types displayed similar trajectories to salinity when plotted as supplemental variables. Moreover, a significant relationship with salinity was observed to varying degrees in all four sub-regions. The abundance of the dominant mesozooplankton functional types increased with increasing salinity reaching peak abundances


113

when hypersaline conditions were present. This may be due in large part to the effect of salinity on mesozooplankton predators, such that in hypersaline waters there are few predators allowing for high mesozooplankton abundance. Interestingly, the number of plankton functional types observed increased with increasing salinity even after hypersaline conditions were achieved. Therefore, if Everglades Restoration results in decreased salinities for Florida Bay the abundance of mesozooplankton may decrease; however, this may not be ecologically detrimental, because it could indicate an increase in the predator population. Of greater concern is the potential for decreased salinities to decrease the diversity of mesozooplankton and thus result in a less resilient mesozooplankton community. An important caveat is that the diversity was calculated not from species richness, but from functional types; thus, species which occupy the same ecological niche are likely not represented in the diversity calculation and resilience may not be adequately captured.

Figure 1. The relationship between mesozooplankton abundance and diversity with salinity indicates that mesozooplankton abundance and diversity increase with increasing salinity. Analyses will be presented which focus on determining if salinity and other environmental parameters are related to the observed temporal and spatial variability in mesozooplankton communities and if high or low salinity extremes have distinct mesozooplankton communities. From these results, hypotheses will be constructed regarding the potential effect of CERP on mesozooplankton in Florida Bay. Contact Information: Christopher R. Kelble, Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA, Phone: 305-361-4330, Fax: 305-361-4447, Email: [email protected]


114

Interactive Effects of Eastern Florida Bay Algal Blooms and Lake Surprise Restoration: Timing Is Everything Stephen P. Kelly, Christopher J. Madden, David T. Rudnick and Kevin M. Cunniff

Everglades Division, Watershed Management Department, South Florida Water Management District, West Palm Beach, FL, USA

An unprecedented, regional phytoplankton bloom (indicated by chlorophyll a concentrations and dominated by Synechococcus spp.) in the eastern boundary waters of Florida Bay and southern Biscayne Bay appeared in late 2005 and has persisted for nearly three years. Lake Surprise (Key Largo, Florida) has been at the center of this bloom (marked by the red area in the left two panels in Figure 1) in part due to its shallow depth and low flushing (long residence time). Results from high resolution water quality mapping documented the development and recent decline of this prolonged algal bloom (Figure 1a-d). Figure 1a shows the averaged results of ten transects conducted during calendar years 2006 and 2007; mean chlorophyll a levels exceeded 10 µg L-1 in much of the area over this time period. Figure 1b-d shows results from transects conducted in 2008, demonstrating progressively declining concentrations, region-wide. While the magnitude and spatial extent of the bloom has greatly decreased, chlorophyll a concentrations in Barnes Sound and Blackwater Sound remain above long-term, pre-bloom (1992-2005) means. In Lake Surprise, concentrations have also decreased in 2008 (from a high of 28 μg L-1 in March 2006), but remain high (5 μg L-1) relative to the surrounding area. Figure 1a-d. Results from high resolution water quality mapping, documenting the recent decline of a prolonged algal bloom in eastern Florida Bay and southern Biscayne Bay. Lake Surprise is a saline lake that has been bisected since 1906 by a causeway built as part of the Key West Extension of the Florida East Coast Railway. The causeway later became the roadbed for the Florida Keys Overseas Highway (U.S. 1). As part of the current U.S. 1 widening project, the causeway is scheduled for removal and will reunite the two isolated halves of the lake for the first time in a century. This restoration effort will reestablish hydrologic connections, improve conditions for the endangered American Crocodile (Crocodylus acutus) and other fauna, and increase access for public recreation. However, causeway excavation activities have the potential to negatively affect water quality in the lake and adjacent waters via increased sediment suspension (turbidity) and nutrient (N and P) loading directly derived from roadbed material or secondarily associated with any subsequent loss of submersed aquatic vegetation (SAV).

Chlorophyll a (μg/l) Aug 26-28, 2008

Barnes Sound

Lake Surprise

Blackwater Sound

1a 1b 1c 1d


115

Lake Surprise currently supports a lush seagrass community dominated by turtle grass (Thalassia testudinum). The condition of the SAV community may determine the success of restoration, as rooted vegetation stabilizes sediments and sequesters nutrients. The timing of causeway removal may be critical to the survival of the lake’s SAV and avoidance of further algal blooms as the vitality of SAV can be negatively affected by higher light attenuation (from increased turbidity) and low dissolved oxygen (DO). In order to determine the status of water column oxygen levels, we initiated baseline (pre-causeway removal) measurements of DO at four sites in Lake Surprise on May 31, 2008. Data showed nighttime DO generally approaching hypoxic levels (2 mg L-1), likely due to high biological oxygen demand (BOD) from nighttime respiration of the water column and benthic communities. Following a heavy rain event on June 18-19, we documented an occurrence of nighttime DO levels near zero (anoxia). Nearly four inches of rain likely stratified the water column and isolated bottom waters from the atmosphere for an extended period, allowing the depletion of DO. During summer and early fall, high water column temperature reduces DO capacity (saturation concentrations), and high nighttime BOD can draw down DO concentrations to low levels. Late summer is also the peak of hurricane season in south Florida. Impact by tropical weather systems may increase turbidity, and rain events can lead to water column stratification and low bottom water DO levels. Decreasing photoperiods, coincident with high temperatures and high BOD in late summer and early fall, also increase the likelihood of low nighttime DO. These multiple factors – temperature, light availability, and stratification – can strongly influence DO concentrations, which can affect the viability of SAV. Maintenance of SAV beds is critical in order to maintain habitat function and minimize the stimulation of further algal blooms. The occurrence of a SAV mortality event could release benthic nutrients and increase turbidity from destabilized sediments, initiating a cycle of phytoplankton growth, low light, and additional SAV loss. If summer causeway excavation were to contribute to a SAV mortality event in Lake Surprise, increased water exchange with adjacent basins may also increase sediment and nutrient export to the wider bay, potentially exacerbating the regional bloom. The potential for anoxia in the late summer and early fall due to high water temperature, high SAV respiration, declining day length, and frequent heavy rain events argues for postponing causeway removal until cooler temperatures prevail. At that time, the risk of negative ecosystem effects would be reduced due to lower water temperature, decreased SAV metabolism, and a decreased threat of severe weather events. Contact Information: Stephen P Kelly, Everglades Division, Watershed Management Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL, 33401, USA, Phone: 561-753-2400 x4646, Fax: 561-791-4077, Email: [email protected]


116

Climate Change Effects on Seagrass Multiple Stressors, Nutrient Cycling and Reproduction: A Perfect Storm in Florida Bay? Marguerite S. Koch

Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA The 2007 Intergovernmental Panel on Climate Change (IPCC) 4th assessment report predicts that by 2100 mean global temperatures will increase by 2-4oC and atmospheric CO2 will reach 560-800 ppm and sea level rise may approach 1 m or more, depending on the tipping points and feedbacks influencing the stability of the Greenland and Antarctic ice sheets. These global changes will lead to higher ocean temperatures, a pH change in the oceans of 0.2-0.5 log units, and shift shorelines and circulation patterns. Shallow marine ecosystems, such as Florida Bay and the Florida Reef Tract already experience temperature and salinity extremes at the upper tolerance levels of their respective foundation species, seagrass, algae and corals. While temperature effects on corals are a focus of current marine research, thermal tolerance of macroalgae and seagrass are only now being examined at the same level. Temperature effects on these species will probably not be straight forward, as temperature affects both plant physiology and ecosystem-level processes in shallow semi-enclosed systems like Florida Bay. Based on experimental and field studies, temperature extremes are primarily affecting bay seagrass community stability indirectly through O2 demand, although the dominant species (Thalassia testudinum) is experiencing temperatures close to its thermal limits (36 oC). While some macroalgal species appear to be highly temperature tolerant, others appear more susceptible to high temperature. In a preliminary study, we found crustose coralline algae to be the most temperature tolerant, but recent evidence shows this group to be highly dependent on a high carbonate saturation state, which is lowered under high pCO2 and a concomitant decline in pH. Carbonate sediments, which store the majority of nutrients in Florida Bay, may also be influenced by a lowering of seawater pH via carbonate dissolution. However, it is more likely that increasing temperature will stimulate microbial activity and sulfate reduction rates, and lead to enhanced carbonate sediment dissolution. Sediment dissolution experiments have been conducted by the authors in Florida Bay, and indicate a relationship between sediment dissolution and P flux from the sediments. This propensity for P to be mobilized with a lower pH is site specific, greatest in western versus eastern bay sites. In addition to biogeochemical considerations, seagrass reproduction may also be influenced by high temperature and salinity by reducing energy reserves for flowering, fruit production and asexual growth via rhizome extension. An important seagrass species at the Everglades-Florida Bay transition zone, Ruppia maritima, may also be limited in its distribution and expansion under a warmer climate with greater heat loads, if increasing fresh water flows from Everglades’s restoration are not adequate to significantly reduce salinity and hypersaline events. Field studies indicate that this species’ reproductive potential and fecundity is arrested during hypersaline and high temperature events in the bay. Further, seed germination of R. maritima is optimal at salinities less than 25 psu. In this talk, a conceptual model will be put forth that outlines the complex changes that may occur in Florida Bay under various scenarios of climate change. While average changes in temperature and ocean acidity predicted in the IPCC report are cause for alarm in ocean and


117

coastal ecosystems, Florida Bay frequently encounters variance in these parameters within the ranges reported for oceans under climate change through the 21st century. However, local climate change effects on estuarine systems in the subtropics are still undetermined. Florida Bay will probably be more at risk from extreme events of high temperature and salinity that would push the resilience of biotic communities in the bay beyond thresholds of tolerance, and initiate a cascade of changes that could lead to an altered ecosystem state. Accelerating slow nutrient regeneration processes may also destabilize this oligotrophic ecosystem. Of course, rapid changes in sea level rise would significantly influence water quality in Florida Bay, compromise the entire benthic community and significantly affect the Reef Tract. A clear focus for research should be on understanding thresholds of benthic community stress at the extremes, along with chronic stress, and how processes in the water column and sediments that shift with a changing climate may synergistically affect the overall stability of Florida Bay as a benthic seagrass–dominated estuary. Contact Information: Marguerite S. Koch, Biological Sciences Department, Florida Atlantic University, 777 Glades Rd. Boca Raton FL 33431, Phone: 561-297-3325, Fax: 561-297-2749, Email: [email protected]


118

Phosphorus Cycling in Florida Bay: A Synthesis Marguerite S. Koch1, Ole Nielsen1, Henning S. Jensen2, Jia-Zhong Zhang3, Chris J. Madden4 and Dave Rudnick4

1Biological Sciences Department, Florida Atlantic University, Boca Raton, FL, USA 2Biology Department, University of Southern Denmark, Odense, Denmark 3NOAA, Ocean Chemistry Division, AOML, Miami, FL, USA 4Everglades Research Division, SFWMD, West Palm Beach, USA

Tropical and subtropical estuaries dominated by fine carbonate particles that efficiently sequester soluble inorganic phosphorus and have low terrestrial P loads can lead to P limitation of primary producers, including both phytoplankton and seagrass. While P limitation is recognized in these marine ecosystems, including Florida Bay at the southern terminus of the south Florida peninsula, P biogeochemical cycling, and the factors controlling recurrent cyanobacterial algal blooms in these systems, is not well understood. Over the last few years, the authors, independently and in collaboration, have significantly increased our understanding of P cycling in Florida Bay through various research endeavors. In this paper, these studies are coalesced and synthesized to provide a more holistic understanding of P-cycling in the bay. We have determined Pi uptake kinetics of seagrass, sediment and the water column across an established nutrient gradient in Florida Bay. We have also quantified the potential for organic P sequestration by water column biota and seagrass via surface cell enzyme hydrolysis. Further, organic matter recycling has been examined by determining the decomposition rates of seagrass tissues and total organic mineralization rates through sulfate reduction. We have estimated the rates of P release to porewaters through carbonate dissolution driven by sulfate reduction, and re-sorption potential. The spatial distribution of P pools in Florida Bay’s fine sediment fraction and kinetics of P adsorption and exchange with respect to the distribution of iron oxides has also provided bay-wide articulation of sediment P-cycling processes. Results of these studies are incorporated into a conceptual model which defines our current understanding of P cycling in Florida Bay, and contributes to a better understanding of the mechanisms that could shift Florida Bay from a benthic to water column dominated estuary. Contact Information: Marguerite S. Koch, Biological Sciences Department, Florida Atlantic University, 777 Glades Rd. Boca Raton FL 33431, phone: 561-297-3325, fax: 561-297-2749, email: [email protected]


119

Interdisciplinary Modeling Support to CERP: Toward Environmental Prediction with the South Florida HYCOM System Villy H. Kourafalou1, HeeSook Kang1, Claire Paris1, Chuanmin Hu2, Peter J. Hogan3 and Ole Martin Smedstad4

1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA 2Institute for Marine Remote Sensing, University of South Florida, St. Petersburg, FL, USA 3Naval Research Lab, Stennis Space Center, MS, USA 4QinetiQ North America, Technology Solutions Group – PSI, Stennis Space Center, MS, USA

The coastal seas around Florida Bay and the Florida Keys Reef Tract exhibit complex dynamics resulting from the connectivity among the surrounding coastal and shelf environments and the interaction with offshore flows, namely the Loop Current/Florida Current system. A nested modeling approach has been employed to ensure the proper representation of such interactions. The modeling system (http://coastalmodeling.rsmas.miami.edu) has adopted the community-based, comprehensive, three-dimensional HYbrid Coordinate Ocean Model (http://hycom.rsmas.miami.edu), a state-of-the-art hydrodynamic model which has been the code source for a recently released real-time global prediction system (http://www7320.nrlssc.navy.mil/GLBhycom1-12/skill.html). Our objective is to dynamically downscale from global (GLB-HYCOM) to basin-wide (Atlantic Ocean, ATL-HYCOM), to intermediate (Gulf of Mexico, GoM-HYCOM), regional (South Florida, SoFLA-HYCOM) and finally coastal (FKEYS-HYCOM) models. This procedure will lead to reliable forecasts in the areas impacted by CERP and will allow even finer scale local models to be embedded, according to specific scientific and management needs. The regional model of the South Florida coastal seas (SoFLA-HYCOM) was initially developed in the framework of CERP; the horizontal grid resolution is ~3.6 km. The high resolution (~900m) FKEYS-HYCOM model has been recently developed, focusing on circulation patterns and coral reef fish recruitment pathways around the Florida Keys. The SoFLA-HYCOM model has been upgraded with boundary conditions from data assimilative simulations of the Gulf of Mexico intermediate model. Improvements in the prediction of currents on the Southwest Florida Shelf are evaluated by comparisons with data. The model has performed simulations with all available regional river inputs provided by the USGS hydrological TIME model. Major freshwater input sources from Shark River to Caloosahatchee River are found to play a significant role in alleviating Florida Bay hypersalinity conditions through intrusions of low salinity waters in the west Florida Bay basin, in support of data findings from salinity surveys. SoFLA-HYCOM outputs have been made available to the South Florida Water Management District to support the EFDC model simulations. The interconnected model domains are displayed in Figure 1. The high resolution FKEYS-HYCOM hydrodynamic model is coupled with the ecological population connectivity BOLTS model (BiOphysical Larval Tracking System). This coupling enables simulations of larval transport, taking into account not only the dispersion of active physical larvae, but also the interaction of factors influencing larval survival, habitat selection and condition at settlement. The biophysical model allows the study of CERP induced impacts of changes in habitat characteristics on coral fish recruitment.


120

The high resolution biophysical simulations allow, for the first time, the modeling of both mescoscale and sub-mesoscale eddy passages during a targeted 2-year simulation period (2004-2005), forced with high resolution/high frequency atmospheric forcing. Eddies enable upwelling of cooler, nutrient-rich waters in the vicinity of the Reef Tract and they influence transport and recruitment pathways for coral fish larvae, as they carry waters of different properties (such as river-borne low-salinity/nutrient-rich waters from as far as the Mississippi River) and waters containing larvae from upstream sources, or entrained from nearby spawning grounds. Moreover, the proximity of the Loop Current/Florida Current front and associated eddies influence sea level changes in the vicinity of Florida Bay with possible implications on current and future flushing patterns. The results are validated with high resolution analysis of satellite data and they reveal the ability of the South Florida HYCOM modeling system to predict eddy evolution along the narrow Florida Keys Atlantic Shelf, with implications for changes in water properties and nutrient concentrations in Florida Bay.

Figure 1: The South Florida modeling system: regional hydrodynamic SoFLA-HYCOM model and coastal biophysical FKEYS-HYCOM model. The interconnected USGS TIME model and SFWMD EFDC model are also shown. Contact Information: Villy H. Kourafalou, University of Miami, Rosenstiel School of Marine and Atmospheric Science, Division of Meteorology and Physical Oceanography, 4600 Rickenbacker Causeway, Miami, FL, 33149, USA, Phone: 305-421-4905, Fax: 305-421-4696, Email: [email protected]


121

On Florida Bay Circulation and Water Exchange with Focus on the Western Subregion Thomas N. Lee1, Nelson Melo2, Ned Smith3, Elizabeth M. Johns4, Ryan H. Smith4, Christopher R. Kelble2 and Peter B. Ortner2

1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA 2Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL, USA 3Harbor Branch Oceanographic Laboratory, Ft Pierce, FL, USA 4Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration,

Miami, FL, USA

The interaction and exchange of Florida Bay waters with coastal waters of the southwest Florida shelf must first occur through the western subregion of the bay, followed by subsequent exchange with more isolated central and northeastern subregions. The initial intrusions of coastal waters takes place through a series of well-defined tidal channels and over broad stretches of shallow, grass covered mud banks. The complexity of the bank-basin physical setting presents formidable obstacles to direct measurement and modeling of interior circulation and water exchange between subregions. We have conducted a series of studies during dry and wet seasons to measure volume transports between subregions, along with salinity patterns and variability that were analyzed with available wind, runoff, precipitation and evaporation data to identify the important physical processes regulating water renewal and estimate residence times. This effort began with the north central subregion in Whipray Basin characterized by its isolation and persistent hypersalinity. We found the high salinities due to poor water exchange, with resulting residence times on the order of a year, lack of river discharge and shallow depths (Lee et al., 2006). The weak exchange rates are clearly associated with the large discontinuity in salinity across the bank separating Whipray from the northeast subregion, which receives around 75% of the fresh water runoff to Florida Bay and maintains estuarine level salinity throughout the year. Weak water renewal rates essentially traps the Everglades discharge in the northeast subregion where residence times are also estimated to be one year (Lee et., 2008). A diversion of a portion of this Everglades discharge to Whipray would therefore be beneficial to the central subregion without negative impacts in the northeast subregion. Our most recent results from the western subregion of Florida Bay show a consistent pattern of local wind forcing generating net basin through-flows that are the primary mechanism for basin water renewal and residence times. The focus of the study was Rabbit Basin and Twin Key Basin during the wet season of 2004 and dry season of 2005. Measurement strategy is shown in Fig. 1 and combines the resources and expertise of UM/RSMAS, HBOI and NOAA/AOML to make time series measurements of currents, temperature and salinity in channels connecting these basins to adjacent waters of the southwest Florida shelf as well as the southeast and north central subregions. Salinity surveys of the western region were made every 2 weeks and of the entire Florida Bay every month. Sea level was measured continuously at stations north and south of 9-Mile Bank to determine the cross-bank sea level slope. Channel current measurements were converted to volume transports using shipboard ADCP transports to calibrate the channels (Lee et al., 2006). The data are rich in results on time scales varying from tidal to seasonal and including extreme hurricane events as well as, El Nino. Seasonal salinity changes in the western basins tend to be the smallest for all Florida Bay, indicating increased exchange with adjacent coastal waters that moderates the seasonal cycle. Active exchange with coastal waters was also indicated by large intrusions of lower salinity waters from the southwest shelf into the western basins during the El


122

Nino influenced dry season of 2005. These intrusions were part of a low-salinity coastal band advected southward around Cape Sable to western Florida Bay. To quantify the magnitude of western basin exchange we use sea level time series from Rabbit Basin with surface area to compute volume anomaly time series and compare to our total channel flow to estimate net flows over the shallow banks. The results show a seasonally averaged basin through-flow forced by the prevailing westward winds with net inflows over the banks and net outflows through the channels of nearly 60 m3/s during the wet season when water levels are higher and about 13 m3/s during the dry season. These significant mean flows produce residence time estimates for Rabbit Basin of 0.5 months for the wet season and 2.2 months for the dry season, which are considerably shorter than the previous estimates for the isolated subregions in the north-central and northeast where flushing times were estimated to be on the order of a year. Transport pathways for waters entering the bay along the western boundary will be discussed.

Figure 1. Location of Rabbit Key and Twin Key basins within the western sub-region of Florida Bay. Current and salinity time series were made during wet (Jun to Nov 2004) and dry (Dec 2004 to Jun 2005) seasons in channels connecting the basins to surrounding regions. Mooring locations are shown with solid triangles and squares. Shown with solid line is the vessel track of the bi-weekly salinity surveys.

References: Lee, T. N., E. Johns, N. Melo, R. H. Smith, P. Ortner and D. Smith, 2006. On Florida Bay hypersalintiy and water

exchange. Bull. Mar. Sci. 79: 301-327. Lee, T. N., N. Melo, E. Johns, C. Kelble, R. H. Smith, P. Ortner, 2008. On water renewal and salinity variability in

the northeast subregion of Florida Bay. Bull. Mar. Sci. 82: 83-105.

Contact Information: Thomas N. Lee, Division of Meteorology and Physical Oceanography, Rosenstiel School of Marine and Atmospheric Research, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA, Email: [email protected]


123

Bottlenose Dolphin Research in Both Florida and Biscayne Bays and the Use of Dolphins as Indicators of Estuary Health Jenny Litz1, Laura Engleby2, Joseph Contillo1, Lance Garrison1 and John Kucklick3

1NOAA, National Marine Fisheries Service, Miami, FL, USA 2Dolphin Ecology Project, St. Petersburg, FL, USA 3National Institute of Standards and Technology, Charleston, SC, USA

Bottlenose dolphins are long-lived, apex predators and their exposure routes to many pollutants and pathogens are the same as humans. Because of these traits, dolphins have been identified as indicators of the health of their habitat and important sentinels for ocean health (Bossart 2007; Hansen et al. 2004; Wells et al. 2004). Photo-identification (photo-ID) techniques using dorsal fin markings have been used to study bottlenose dolphin populations in both Florida Bay and Biscayne Bay. The Dolphin Ecology Project has supported research efforts in Florida Bay since 1999 and presently has over 500 individual dolphins in their photo-ID catalog. The study area includes portions of both the Everglades National Park and the Florida Keys National Marine Sanctuary and encompasses 2,200km². Based on recent summer photographic mark-recapture surveys, estimates of bottlenose dolphin abundance indicate there are approximately 514 dolphins that utilize Florida Bay in May (Read et al., in review). Many animals appear to have strong site fidelity in different zones throughout Florida Bay. The Biscayne Bay research, conducted by the National Marine Fisheries Service, began in 1990 and the historic study area extends from Haulover Inlet in the north to Card Sound Bridge in the south including the Biscayne Bay Aquatic Preserve and portions of Biscayne National Park. This year, the study area has been expanded to include Barnes Sound to the south and areas along the coast just outside of Biscayne Bay. There are more than 200 individual dolphins in the catalog and many of them appear to be year-round residents. The Biscayne Bay community is divided into at least two social groups with overlapping home ranges. The northern social group, sighted primarily in the northern, metropolitan half of the Bay, and the southern group, sighted primarily in the southern, less developed half of the Bay (Litz 2007).

Although bottlenose dolphins are capable of moving large distances daily, they can show a high degree of site fidelity. Significant genetic structure was found between 78 Biscayne Bay and 53 Florida Bay dolphins using mitochondrial DNA and 10 nuclear microsatellite markers (FST = 0.14, p<0.01 and FST = 0.04, p<0.01 respectively) (Litz 2007). The genetic differentiation found between Florida Bay and Biscayne Bay dolphins in both maternally-inherited mtDNA and biparentally inherited nuclear markers indicates little genetic mixing between the two dolphin populations, and provides evidence for both male and female site-fidelity to their respective Bays.

Blubber samples from 46 Biscayne Bay dolphins were analyzed for persistent organic pollutants (POPs) including, 73 polychlorinated biphenyl (PCB) congeners, 6 polybrominated diphenyl ether (PBDE) congeners, and pesticides including DDT and metabolites, chlordanes, and dieldrin. Total PCBs (Σ73PCBs) were present in the highest concentrations and were 5 times higher in males with sighting histories in the northern, metropolitan area of Biscayne Bay than males with sighting histories in the southern area [GM: 43.3 (95% CI: 28.0 – 66.9) vs. 8.6 (6.3 - 11.9) μg/g wet mass respectively] (Litz et al. 2007). All compound classes examined had higher concentrations in northern animals than southern. The POP concentrations, particularly PCBs in northern Biscayne Bay dolphins, are high compared to other studies of estuarine dolphins, including Florida Bay. The high concentrations found suggest that the northern Biscayne Bay


124

dolphins may be at risk of reproductive failure and decreased immune function. The geographic trend of POP concentrations in dolphins matches the trend found in Biscayne Bay sediments, with high levels of PCBs in northern sediments compared to southern sediments (Cantillo et al. 1999). This confirms that the dolphin POP profiles are reflective of differences in the bioavailable organic pollutants in the habitat. The high concentrations found raise concerns about the levels of bioavailable POPs in the Biscayne Bay food chain including fish species that may also be consumed by humans. Future work will include investigating POP concentrations in Biscayne Bay fish.

Both Photo-Id and genetic techniques support the presence of distinct communities of dolphins in each of Florida and Biscayne Bays. The high-level of site fidelity and long-term residency patterns make them ideal candidates for sentinels of ecosystem health in their respective estuaries. This study has shown that dolphins can reflect the patterns of organic pollutants in the ecosystem on a very small geographic scale. Understanding the ranging patterns and habitat use of these animals is critical to interpreting data on environmental stressors. Health and exposure research on both of these dolphin populations should be continued and may prove useful when investigating changes over time. References: Bossart GD. 2007. Emerging diseases in marine mammals: from dolphins to manatees. Microbe 2(11):544-549. Cantillo AY, Laurenstein GG, O'Conner TP, Johnson WE. 1999. Status and trends of contaminant levels in biota

and sediments of South Florida. National Status and Trends Program, Regional Reports Series 2 http://www.ccma.nos.noaa.gov/publications/southflorida.pdf. 40 p.

Hansen L, Schwacke L, Mitchum GB, Hohn AA, Wells RS, Zolman E, Fair P. 2004. Geographic variation in Polychlorinated Biphenyl and organochlorine pesticide concentrations in the blubber of bottlenose dolphins from the US Atlantic coast. The Science of the Total Environment 319:147-172.

Litz JA. 2007. Social structure, genetic structure, and persistent organohalogen pollutants in bottlenose dolphins (Tursiops truncatus) in Biscayne Bay, Florida [PhD]. Miami, FL: University of Miami. 140 p.

Litz JA, Garrison LP, Fieber LA, Martinez A, Contillo JP, Kucklick JR. 2007. Fine-scale spatial variation of persistent organic pollutants in bottlenose dolphins (Tursiops truncatus) in Biscayne Bay, FL. Environmental Science and Technology 41(21):7222-7228.

Read A.J., K. Urian, L. Engleby, D. Waples, B. Wilson. 2008. Abundance of bottlenose dolphins in Florida Bay. Bulletin of Marine Science. In Review.

Wells RS, Rhinehart HL, Hansen LJ, Sweeney JC, Townsend FI, Stone R, Casper DR, Scott MD, Hohn AA, Rowles TK. 2004. Bottlenose dolphins as marine ecosystem sentinels: developing a health monitoring system. EcoHealth 1(246-254):246-254.

Contact Information: J. Litz, NOAA, National Marine Fisheries Service, 75 Virginia Beach Drive, Miami, FL 33149, USA, Phone: 305-361-4224, Fax: 305-361-4221, Email: [email protected]


125

Phycobilin Analysis Protocol Development for Ground-Truthing Cyanobacterial Field Monitoring in Florida Bay and Adjacent Marine Systems J. William Louda1, Stephen P. Kelly2 and Panne Mongkhonsri1

1Organic Geochemistry Group, Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL

2Everglades Division, South Florida Water Management District, West Palm Beach, FL Phycobilipigments are primary photosynthetic pigments (PPPs) in cyanobacteria, cryptophytes and rhodophytes that absorb light mainly through the range of about 400-650 nm. In the case of the cyanobacteria, the chlorophyll-a and carotenoids (zeaxanthin, β-carotene, echinenone, myxoxanthophyll, and others, all exhibiting species specificity as to distribution) function as accessory pigments to the phycobiliproteins which are the antenna complexes (in phycobilisomes, PBSs) or sunscreens. Cyanobacterial species belonging to the genus Synechococcus are prevalent in the open ocean as well as forming extensive blooms in Florida Bay and adjacent waters (refs. in Louda, 2008; Rudnick et al., 2007). Anthropogenic influences (~nutrient enrichment) have led to severe increases in nuisance blooms, mainly cyanobacteria and dinoflagellate, in many coastal systems (Paerl, 1988). Around south Florida and the Florida Keys, the export of nutrients from land can be a cause of such blooms. Blooms of cyanobacteria (>86%) by pigment chemotaxonomy; Louda in Rudnick et al., 2007) started in 2005 in waters proximal to an area of road construction on US Highway 1 near Key Largo, FL. Blooms may have been stimulated by multiple factors, including a large discharge of fresh water and phosphorus to the area as well as disturbance from Hurricanes Katrina, Rita and Wilma; the associated high winds, waves and storm surge may have exported materials from mixed soils adjacent to US1 into the waters of Manatee Bay, Barnes and Blackwater Sounds. The South Florida Water Management District (SFWMD) has been utilizing a Turner Designs C-6 multi-sensor instrument (with sensors for chlorophyll-a, phycocyanin and phycoerythrin), in addition to several other methodologies, for high resolution mapping of phytoplankton populations and bloom dynamics in the marine and estuarine areas around the southern tip of Florida. Routine chlorophyll-a measurements offers a proxy for the total oxygenic photosynthetic biomass. However, the addition of phycobiliprotein monitoring offers a faster assessment of cyanobacterial bloom onset, presence and dynamics. To calibrate the in-vivo fluorescence measurements requires the development of extraction, quantitation, and separation / identification methodologies that will be facile, precise and accurate. Rather than starting from the ‘ground up’, we have done a relatively expansive literature search and, after reviewing these articles, books and theses, have settled on a general analytical desiderata for the analyses of phycobiliproteins and their phycobilin prosthetics groups. From the literature base, we must concur with the following quote: “However, there is no standard protocol for extracting and quantitating these proteins from cyanobacterial cells.” (Viskari and Colyer, 2003).


126

Following extended extraction tests with both unialgal cultures and field samples, we developed an extraction procedure modified from 3 previously published methods. Extracts were then spectrally measured with both UV/Vis and fluorescence spectrophotometers at the following wavelengths: UV/Vis at 562,565,615,620,650, 652, and 715nm. Fluor at Ex / Em = 510 / 573 nm (PEB) , 550 / 636 nm (PCB), and 550 / 658 nm (APCB) and concentration data generated using the equations of both Bennett and Bogorad (1973) and Roman et al. (2002). Standard phycobiliproteins purchased from ProZyme Inc. (phycocyanobilprotein (PCB), allophycocyanobiliprotein (APCB), and B- and R-phycoerythobiliprotein (B-PEB, R-PEB)) were used for quality assurance/quality control (QA/QC) standardization of UV/Vis spectral measurements, preparation of known mixtures (PCB/APCB, PCB/PEB, PCB/APCB/PEB) and cross calibration of UV/Vis with fluorescence. All methods were tested using dilution series made from unialgal cultures (Anabaena flos-aquae, Microcystis aeruginosa) and natural field samples (West Lake, Lake Surprise, Barnes Sound and a fresh water pond). Cross checks of dilution linearity were made using chlorophyll-a measurements and in all cases R2 values were greater than 0.98. In addition, all samples had a zero intercept except the sample from West Lake. West Lake is located in the mangrove transition zone in north central Florida Bay with very high concentrations of colored dissolved organic matter (CDOM). Presently, we can but conjecture that this may be interfering with the in-vivo fluorescence signal but this is still under investigation. The results of this protocol study will allow in-vivo fluorometric measurements to be quantitatively converted to phycobiliprotein concentrations. Future work will include cross calibration with both unialgal cultures and field samples enumerated with an automatic optical cell counter (Coulter). In addition, pigment-based chemotaxonomy (Louda, 2008), using Division / Class specific carotenoid and/or accessory chlorophyll (-b, -c’s) biomarkers, will be used to address overall phytoplankton community structure. These methods should allow not only the detection of cyanobacterial bloom formation but also an understanding of the dynamics of such blooms when coupled to water quality parameters. References: Bennet, A. and Bogorad, L. (1973) J. Cell Biol. 58, 419 - 435. Beutler, M. (2003) Thesis, Ph.D. University of Kiel, Kiel. Louda J.W. (2008) J. Liq. Chromatogr. Rel Tech., 31: 1- 28. Paerl H. W. (1988) Limnol. Oceanogr. 33, 823 – 847. Roman, R.B. et al. (2002) J. Biotech. 93, 73 – 85. Rudnick, D.S. et al. (2007) South Florida Environmental Report, Appendix 12-3. Viskari, P.J. and Colyer, C.L. (2003) Analyt. Biochem. 319, 263 – 271.

Contact Information: J. William Louda, Organic Geochemistry Group, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431,USA, Phone: 561-297-3309, Fax: 561-2972759, Email: [email protected]


127

Pigment-based Chemotaxonomy of Florida Bay Phytoplankton and the Influences of Photic Flux J. William Louda, Cidya S. Grant and Panne Mongkhonsri

Organic Geochemistry Group, Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL

The main principle of pigment – based chemotaxonomy rests with the ability to dissect the pigment assemblages of natural microalgal communities in such a way so as to relate taxon specific biomarker pigments to the amount of chlorophyll a (CHLa), as a proxy for biomass, contributed by each group to the total community CHLa (Millie et al. 1993). Thus, certain pigments are utilized for the quantitative assessment of taxa (Division, Class) present in mixed natural communities. Examples include: fucoxanthin for the Chrysophytes, especially diatoms; chlorophyll-b for chlorophytes, alloxanthin for cryptophytes, and for cyanobacteria zeaxanthin or echinenone for coccoidal or filamentous forms respectively (Louda 2008). We have previously reported aspects of these studies in the waters of Florida Bay and the Mangrove Lakes of its fringe (Louda et al. 2000; Louda 2001, 2005 etc.). Notably the wax/ wane and presence of cyanobacteria (Synechococcus elongatus) in north-central Florida Bay has been followed with these methods. Sourcing of bloom innocula from the Mangrove Lake series has been of interest by the senior author for many years. As recurrent blooms in northern and central bay are mainly unicellular cyanobacterial in nature, the simple pigment profile of these organisms (chlorophyll-a [CHLa], β-carotene and zeaxanthin[ZEA]) forces the use of the sunscreen pigment zeaxanthin as a ‘quantitative’ biomarker for these populations. As we reported previously (Louda 2005, 2008), the cyanobacterial blooms in Whitewater Bay versus Florida Bay gave CHLa/ZEA ratios of 2.5:1 and 1:1, respectively. The lower relation of ZEA to CHLa in Whitewater Bay, we attribute to additional ‘sunscreen’ activity related to the high humic nature of those waters relative to the open bay. Previous work with this species provided from a culture provided by Dr. Carmelo Tomas, revealed a CHLa/ZEA ratio of 5:1, indicating an even lower requirement for sunscreen in culture. Going on the hypothesis that photic flux will significantly perturb CHLa / biomarker pigment ratios, we have been performing in depth studies of the effect of light on these ratios in order to better understand this driver and then to adjust the simultaneous linear equations utilized to estimate the (chemo-) taxonomic makeup of natural phytoplankton communities. Figures 1 and 2 are the plots of CHLa to selected pigments in the cyanobacterium Anacystis nidulans (aka Synechococcus sp.) and the chlorophyte Closterium aecerosum. The decrease in CHLa / ZEA and CHLa / lutein, repectively, indicates that the primary function of these carotenoids is photoprotection. Similar data obtained for diatoms and dinoflagellates reveal that their main carotenoids, fucoxanthin and peridin respectively, are main photosynthetic accessory pigments (PAP) since the ratio of CHLa to these biomarkers remain relatively stable. Similarly, CHLa / CHLb ratios reveals CHLb role as a PAP rather than as a sunscreen. In this manner, we are adjusting the ratios we use for the estimation of the various phytoplankton taxa. That is, the consideration of photic flux (~light field) is being addressed as an easily obtained field measurement with which to adjust our estimation equations (cf. Louda, 2008).


128

Anacystis nidulans: chla/zea v. light intensity

2.9

1.251.89

1.07 1.05

0

1

2

3

4

0 500 1000 1500 2000

Light Intensity (umol.m-2.s-1)

Chl

a/ze

a

Closterium acerosum CHLa to CHLb(____) or Lutein (- - - -) Ratios

0

2

4

6

8

10

12

14

16

0 500 1000 1500 2000Light (umol phota m-2 s-1)

RATI

O (C

HLa

: CHL

b or

LUT)

Figure 1: Chlorophyll-a to zeaxanthin in the Figure 2: CHLa to CHLb (solid) or lutein cyanobacterium Anacyctsis nidulans. (dashed) in the chlorophyte C. acerosum. In August of 2007, water samples were collected throughout the Mangrove Lake series from West Lake to Alligator Creek. These were analyzed and chemotaxonomic estimates made. Figure 3 contains the histogram representation of that chemotaxonomic output. Aside from an larger relative abundance (20%) of chlorophytes in the phytoplankton of West Lake (CHLa = 37 μg/L, 14.4‰), this series of lakes had 80 – 90+% cyanobacterial biomass in very large amounts (34-40 μg CHLa/L), certainly more than enough to serve as seed innocula upon movement of these waters into the bay. Previously, we reported cyanobacterial bloom spread from Garfield Bight, just outside Alligator Creek, into Snake Bight and Whipray Basin (Louda, 2001,2005).

CYANO

CHLORODIAT

DINO

CRYPTO

W.LakeMid-Long Lake

LungsAlligator / Lungs

Alligator Creek Pond

0

10

20

30

40

50

60

70

80

90

100Total Chlorophyll-a34-40 μg / L

S = 14 - 19 ‰

Figure 3: Chemotaxonomic estimation of phytoplankton in the Mangrove Lakes. Acknowledgements: These studies (JWmL) have been supported by the National Oceanographic and Atmospheric Administration, through the Marine Fisheries Division (2000-2003), the South Florida Water Management District and the Comprehensive Everglades Restoration Plan-Monitoring and Assessment Program. That support is greatly appreciated. The gift of cultures of Synechococcus elongatus by Dr. Carmelo Tomas and recent sampling adventures into the Mangrove Lake system with Dr. Tom Frankovitch are likewise very much appreciated. Contact Information: J. William Louda, Organic Geochemistry Group, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431,USA, Phone: 561-297-3309, FAX: 561-2972759, email: [email protected]

References: Louda, J.W. (2001) Fla. Bay & Adj. Mar.

Sys. Sci. Conf. Key Largo. April 23 –26. Louda, J.W. (2005) Fla. Bay & Adj. Mar.

Sys. Sci. Conf. Hawks Key, Dec.11-14. Louda, J.W. (2008) J. Liquid Chromatogr. &

Rel.Tech. 31: 295-323. Louda et al. (2000) Org. Geochem. 31 (12):

1561 – 1580. Millie et al. (1993) Can. J. Fish. Aquat. Sci.

50: 2513-2527.


129

A Synthesis of Models to Simulate Benthic-Pelagic Coupling in Florida Bay: Examination of Ecosystem Restoration and Climate Change Effects Christopher J. Madden and Amanda A. McDonald

Everglades Division, South Florida Water Management District, West Palm Beach, FL USA Ecological restoration of the ecosystems of south Florida is based on integrated, whole-system planning, design and adaptive management of the water system. Biogeochemical and habitat relationships within subsystems of the Greater Everglades ecosystems are dependent on the repair of hydrological function. The Comprehensive Everglades Restoration Plan (CERP) for the Everglades and Florida Bay is an ecosystem-based management (EBM) restoration strategy that relies in large part on simulation modeling at multiple levels for evaluating management alternatives, for predicting component responses to ecosystem changes and for setting restoration targets. Ecological, hydrologic and circulation models are fundamental components of the restoration modeling toolkit. Major models characterizing aspects of the hydrology of the Everglades wetland surface and subsurface flows across different domains and at spatial scales include the South Florida Water Management Model (SFWMM), the Tides and Inflows in the Mangrove Ecotone model (TIME) and the Southern Inland and Coastal Systems model (SICS). Inputs of water to Florida Bay from Everglades overland flow, ground water and point discharge represent the boundary condition for Florida Bay models. Hydrologic transport, water and salt balance in Florida Bay are calculated within the Flux Accounting and Tidal Hydrology Ocean Model (FATHOM) framework at a coarse spatial (basin-level) and temporal (monthly) scale. The Environmental Fluid Dynamics Code model (EFDC) is a 3-D finite difference hydrodynamic model that provides water circulation and salinity distribution for Florida Bay at extremely fine spatial and temporal scales, including in the vertical dimension. The South Florida Hybrid Coordinate Ocean Model (SoFLA-HYCOM) simulates ocean hydrodynamics in the southern Florida coastal Atlantic Ocean, Florida Straits and Gulf of Mexico waters, provides the boundary condition for Florida Bay internal model hydrodynamics and describes the important inflow of Gulf water to the northwest sector of Florida Bay. This input represents a major source of P to the bay. These physical models of water and salt movement are coupled to higher order models that simulate aspects of the biogeochemistry and plant/animal ecology of Florida Bay. Ecological models are being used to design management strategies, operational parameters and predict likely outcomes in the context of global climate change. A mechanistic unit model of benthic-pelagic interactions has been developed for the Florida Bay seagrass and phytoplankton community that describes daily and annual biomass, production, species composition and distribution potential for three SAV species: Thalassia testudinum, Halodule wrightii, and Ruppia maritima. The Florida Bay Seagrass Community Model (SEACOM) is a stand-alone computational framework that also forms a core part of the Florida Bay EFDC water quality model primary production algorithm, providing a spatially explicit water transport model yielding a landscape-based tool. When SEACOM is used stand-alone, FATHOM and EFDC physical model outputs of salt and water balance are used by the SEACOM unit model to drive salinity inputs and water turnover rates at the basin-scale. The model is calibrated for eight basins representative of different sectors within the estuary and describes the growth, community composition, physical structure and nutrient dynamics of the seagrass community, as well as interactions with the water column and phytoplankton processes. Evaluations of salinity


130

requirements for the benthic-based seagrass community based on the timing, salinity and nutrient composition of freshwater inflows are used in determination of restoration design and operations. The increasingly variable nature of generally oligotrophic Florida Bay has poised its trophic status between alternate stable states of benthic and planktonic dominance, and may provoke oscillatory behavior or result in a permanent new set-point around a pelagic-based algal system (Figure 1). The model is run using different basin flushing rates and internal nutrient cycling rates to determine physical thresholds that may represent tipping points for system change. Nutrient and salinity thresholds are calculated for shifts in benthic macrophyte dominance and for large scale benthic-pelagic changes in state. Against this backdrop, with water management projects being implemented on an ecosystem scale, it is important to understand consequences to the ecosystem, particularly secondary or cascading responses, as well as the likelihood of restoration success, within a dynamically changing climatology. SEACOM has the capability to incorporate effects of global and local climate change by adjustments to simulate altered temperature, increased freshwater flow and increasing sea level. These scenarios are driven by links to outputs of climate models to reflect potential ecosystem response to management and climate interactions. Model output of seagrass habitat quality and extent is being used in predictive General Additive Models (GAM) of upper trophic levels, focusing on density and composition of the forage fish community, pink shrimp and top consumers. Habitat suitability models are also being developed for Florida Bay using a variety of data and modeled inputs to predict the probabilities of habitat suitability for several upper trophic level species under a variety of water flow and nutrient scenarios. This presentation discusses the capabilities and limitations of this complex simulation environment of interlinked models. It will focus on how syntheses of models can be adapted to interact with global climate models to predict ecosystem responses in the Florida Everglades to potential climate change and sea level rise. Contact Information: Christopher J. Madden, Everglades Division, South Florida Water Management District, 8894 Belvedere Rd. West Palm Beach, FL 33411, USA, Phone: 561-686-8800 ext 4647, Fax: 561-791-4077, Email: [email protected].

Figure 1. Model run showing example of Barnes Sound seagrass community with 50 d turnover time and 85% recycling factor and injection of phosphorus in year 7 resulting in a three-year phytoplankton bloom and loss of SAV.


131

A Comparison of the Pre-drainage Everglades Hydrology and Florida Bay Salinity Based on Paleoecology from Multiple Sediment Cores Coupled with Statistical Models Frank E. Marshall1, G. Lynn Wingard2, Patrick Pitts3, Evelyn Gaiser4 and Ania Wachnicka4

1Cetacean Logic Foundation, Inc., New Smyrna Beach, Florida, USA 2US Geological Survey, Reston, Virginia, USA 3US Fish & Wildlife Service, Vero Beach, Florida, USA 4Florida International University, Miami, Florida, USA

Paleoecological data have been collected from a number of locations in Florida Bay, Everglades National Park (ENP). Sediment cores have been interpreted to estimate the age and pre-drainage salinity regime at the location of the core. Statistical models have been developed from observed data and coupled with the paleoecological data to estimate the pre-drainage stage and flow conditions in Shark River Slough and Taylor Slough and salinity throughout Florida Bay. For this project the estimates developed for four sites in the Bay will be assimilated to provide a more complete salinity and hydrology history. The information from this body of evidence can then be used to guide restoration of the natural hydrology and improved salinity conditions in ENP to the extent possible. At three of these sites the paleoecological data collected by the USGS Ecosystem History of South Florida’s Estuaries Project using mollusk assemblage data is being used. At one site the paleoecological diatom characterizations by Florida International University (FIU) was used. From these separate efforts, independent estimates of the pre-drainage salinity regime have been developed for comparison as a body of evidence. To estimate the pre-drainage conditions at these multiple sites, a three phase process was developed to couple paleoecologic assemblage data and regression models1. In the first phase the paleoecological analysis establishes the target salinity regime for pre-drainage conditions. Paleoecologic studies provide a method of reconstructing pre-existing biological, physical and chemical parameters of an ecosystem through analysis of the biotic remains of organisms preserved in sediment cores. For the second phase, regression models for stage, flow, and salinity are developed from ENP Marine Monitoring Network instrumental data. For phase three, the products of phases one and two are coupled to estimate the paleo-based hydrology in the Everglades that would create the pre-drainage salinity regime in Florida Bay. Also, in phase three the paleo-based salinity conditions at various locations throughout Florida Bay are estimated.

Using this approach at Whipray Basin, the overall mean values produced by the models indicate that existing freshwater flows into the remaining Everglades are about 2-2.5 times lower compared to the pre-drainage period. The deficit in Taylor Slough is much greater than Shark River Slough in the dry season. Stage at P33 and Craighead Pond (key stations for CERP performance measure evaluations) are about 0.15 meters lower on average now than during the pre-drainage period. The average hydroperiod has also been reduced significantly over pre-drainage estimates, with the Taylor Slough hydroperiod reduced more than Shark River Slough. The pre-drainage salinity regime across Florida Bay was oligohaline to polyhaline compared to the existing conditions of mesohaline to euhaline2.


132

A similar analysis using the paleoecological data collected at Bob Allen Key by FIU produced estimates of pre-drainage stage and flow that are higher than the estimates based on the Whipray Basin paleoecological data3 though a hurricane may have confounded the paleo analysis at the Bob Allen Key site. Additional analyses are underway at two other sites in Florida Bay in conjunction with the USGS. The Southern Estuaries Sub-team of RECOVER uses performance measures to the effectiveness of Comprehensive Everglades Restoration Plan (CERP) improvements. The current performance measures utilize Natural System Model (NSM) based estimates of salinity. Comparisons of NSM-based estimates and paleo-based estimates in Florida Bay indicate that the paleo-based salinity conditions are considerably fresher than the NSM-based regime. The multiple lines of evidence approach described herein will verify or modify the single-station and NSM-based estimates of historical hydrology and salinity conditions, and may have significant implications for CERP evaluations. The ultimate objective is a corroborated estimate of the stage and flow regimes for Shark River Slough and Taylor Slough necessary to meet pre-drainage salinity targets, and the resultant spatially-broad, paleo-based salinity regime in the Bay. A comprehensive paleoecological study of the ecosystem history will also require the use of the linked paleo / regression model methodology for the existing cores in the Shark River, currently a gap in the evaluation. References: 1Marshall III, F. E., G. L. Wingard, and P. Pitts. 2008, draft. A Simulation of Historic Hydrology and Salinity in

Everglades National Park: Coupling Paleoecolgic Assemblage Data with Regression Models. Manuscript submitted to Estuaries and Coasts, the Coastal and Estuarine Research Federation.

2Marshall III, F. E. 2008. RECOVER Southern Estuaries and Greater Everglades Performance Measures: Estimation of Hydrology-Salinity Regimes from Paleo-Ecological Indicators, Projected Sea-Level Rise and Project Effects of the Atlantic Multi-decadal Oscillation (AMO) for use in the Evaluation of Comprehensive Everglades Restoration Plan (CERP) Restoration Scenarios. Task 1: Estimating the Pre-drainage Everglades Hydrology and Florida Bay Salinity Using Paleoecology and Regression Models. Environmental Consulting & Technology, Inc. New Smyrna Beach, FL.

3Marshall III, F. E. 2008. 2008, draft. The Use of Statistical and Mass Balance Models for the Improvement of Interim Goal Indicators. Task 5: Verify and Improve Estimates of Pre-drainage Freshwater Flow. CESI Cooperative Agreement H5284-07-0076. Cetacean Logic Foundation, Inc. New Smyrna Beach, FL.

Contact Information: Frank E. Marshall, Cetacean Logic Foundation, Inc., 109 Esther Street, New Smyrna Beach, Florida 32169, USA, Phone: (386) 423-4278, Fax: (386) 423-4278, Email: [email protected].


133

In situ Measurements of Sponge Respiration, Nitrification and ANAMMOX on the Florida Keys Reef Tract Christopher S. Martens1, Niels Lindquist2, Patrick Gibson1, Howard Mendlovitz1, James Hench3 Brian Popp4, Richard Camilli5, Anthony Duryea6, Robert Byrne7, Lori Adornato8 and Xuewu Liu8

1Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA 2Institute of Marine Sciences, UNC–Chapel Hill, Morehead City, NC 3Department of Civil and Environmental Engineering, Stanford University, CA 4Department of Geol&Geophys, University of Hawaii-Manoa, Honolulu, HI 5Appl Ocean Phy&Eng, Woods Hole Oceanographic Institution, Woods Hole, MA 6Monitor Instruments Company LLC, Cheswick, PA 7College of Marine Science, University of South Florida, St Petersburg, FL 8SRI International, St Petersburg, FL

Marine sponges are abundant on the Florida Keys reef tract, nearshore patch reefs and in Florida Bay, often comprising the majority of the benthic biomass. Modes and rates of whole sponge respiration, nitrogen cycling and pumping rates vary over ten-fold between dominant species correlating with the abundance of microbial communities hosted within their tissues. High microbial abundance (HMA) sponges exhibiting rapid respiration rates host highly efficient microbial biogeochemical transformations including nitrification and ANAMMOX (Anaerobic Ammonium Oxidation). Thus, sponge tissue stable C and N isotopic compositions should reflect not only organic matter sources and animal respiration but also microbial C and N transformation processes. We used novel new underwater technologies including in situ Membrane Inlet Mass Spectrometry (MIMS), acoustic Doppler velocimetry (ADV) and nutrient and pH spectrophotometry (SEASII) for periods of hours to weeks to determine the rates of various C and N cycling mechanisms under variable ambient dissolved oxygen concentrations. The overall goal was to understand the mechanisms controlling and to measure net chemical fluxes from representative HMA and Low Microbial Abundance (LMA) sponges. Significantly lower pumping rates by HMA sponges result in longer water residence times within their tissues, hypoxic conditions and preferential net export of DIN as dissolved nitrate. We report here the first proof for in situ ANAMMOX (NH4

+ + NO2- → N2 + 2H2O) by HMA sponges common to

the Florida Keys. The conversion of DIN concentrations into harmless N2 gas by ANAMMOX, if proven to be widespread, represents an important potential pathway for reducing nitrogen loading on coral reefs and other marine ecosystems where HMA sponges are abundant. Differences in sponge tissue oxygenation between HMA and LMA sponges appear to represent an important control on observed differences in net N transformations. In situ measurements of oxygen concentrations in HMA and LMA sponge tissues made with needle-style oxygen microsensors revealed extreme concentration gradients with hypoxic conditions generally occurring within a few mm depth in HMA sponges with LMA species generally having patchy oxygenation ranging from hypoxic to near saturation concentrations throughout their tissues. Anecdotal evidence and several recent publications suggest that sponge biomass has been changing in some coral reef ecosystems, perhaps in association with changes in coral cover. Massive losses of sponge biomass have been documented in Florida Bay during cyanobacterial bloom events. Our results show that sponge biogeochemical cycling plays a major role in both C and N transformations and net fluxes in coral reef and probably in all coastal environments


134

wherever sponge biomass is significant. Changes in sponge biomass should have significant consequences for dissolved as well as particulate matter cycling in these ecosystems. Contact Information: Christopher S. Martens, CB-3300, Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3300 USA, Phone: 919 962 0152, Fax: 919 962 1254, Email: [email protected]


135

Florida Bay Seagrass Dynamics: A Modeling Study of Interspecific Competition, Salinity, and Nutrient Control Amanda A. McDonald1, Christopher J. Madden1 and Marguerite S. Koch2

1Everglades Division, South Florida Water Management District, West Palm Beach, FL, USA 2Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL, USA

A dynamic seagrass community model was developed and applied in Florida Bay to evaluate effects of changes in freshwater inputs due to Everglades restoration and climatic variability. Model analysis is being used in developing MFLs (Minimum Flows and Levels for Florida Bay) and for restoration planning (Florida Bay Florida Keys Feasibility Study - FBFKFS) for the southern Everglades and Florida Bay. The model currently simulates biomass of three species, Thalassia testudinum, Halodule wrightii, and Ruppia maritima, for eight different sectors of the bay using growth functions governed by light, salinity, sulfide, temperature, plant density, and nutrients. Expansion of Ruppia and increased Halodule abundance are two performance measures specified in CERP (Comprehensive Everglades Restoration Plan) restoration strategies. Parameters for the model have been derived from experiments specifically targeted for this project, from unpublished datasets from Florida Bay and existing literature. Despite their wide salinity tolerance ranges, there is a clear pattern observed in the field in the distribution of the three seagrass species. Monitoring data show that Thalassia is distributed throughout the meso and high salinity areas of Florida Bay, often mixed with Halodule, while Ruppia is confined almost exclusively to the lowest salinity waters. Halodule can become the dominant species near freshwater inflow areas where salinity is highly variable. Mesocosm experiments show that adult plants of all three species are tolerant of extended periods of hypersalinity as well as periods of low salinity. Although adult Ruppia tolerates salinity in excess of 60 psu in mesocosm experiments, it is found only in some creeks, lakes and ponds in the mangrove ecotone. The modeling study of interspecific competition and environmental stresses that we describe examines the mechanisms underlying the current distribution of seagrass in Florida Bay and projects species distributions with the restoration of freshwater flow. The model is being used in conjunction with continuing experiments to determine the physiological and ecological factors underlying observed distributions, and ultimately, to improve our ability to forecast changes in seagrass communities and their function with Everglades restoration as well as under scenarios of climate change. A simulated transect was modeled consisting of four sites along an estuarine salinity gradient from near-fresh to saline to evaluate the influence of salinity and sediment nutrient regimes on seagrass species distribution. The sites consisted of an upstream coastal pond (Pond 5 in Taylor River, 0-40 psu mean= 6); a near-shore embayment (Little Madeira Bay at the mouth of Taylor River, 0-39 psu, mean= 13); a northeastern Florida Bay site (Eagle Key Basin at the mouth of Little Madeira Bay, 5-38 psu, mean= 20); and a high salinity site in central Florida Bay (Whipray Basin, 21-50 psu, mean= 34). These sites differed in sediment depth, sediment organic matter content, light penetration, and water column N and P concentrations. Resource competition is implicit as all species utilize the same nutrient pools and available light and no allelopathy is assumed. The model study simulation length was five years with a subdaily timestep, tracking biomass and species composition. Model results showed that predictable spatial distributions result from the combined effects of interspecific competition and environmental conditions. Thalassia could out-compete Halodule by a combination of shading of the other species and an advantageous nutrient storage function that favors Thalassia during periods of low nutrient availability. The slower turnover rate of Thalassia allows it to maintain biomass across years


136

even with reduced peak specific production during the growing season. Thalassia abundance was not negatively impacted by the presence of other species in mixed beds; its productivity was controlled more strongly by sediment depth, hydrogen sulfide and salinity regime. Contrastingly, Halodule is a faster growing species that was able to initially out-compete Thalassia in denuded or bare areas. Because of the lower storage capacity for photosynthate and more rapid turnover rate, Halodule must have a higher level of continuous production to maintain existing biomass intra- and inter-annually. Model predictions of Ruppia distribution showed growth response similar to that of Halodule in which environmental impacts couple with competition impacts control survival in adult plants. The confinement of the species to fresher areas is apparently accounted for by the failure of seeds to germinate successfully in salinities higher than 30 psu. Contact Information: Amanda A. McDonald, Everglades Division, South Florida Water Management District, Field Operations Center B-260, 8894 Belvedere Rd, West Palm Beach, FL, 33411, USA, Phone: 561-753-2400 x4648, Fax: 561-791-4077, Email: [email protected]


137

South Florida Coastal Oceanographic Database Nelson Melo1, Thomas N. Lee2, Elizabeth M. Johns3, Ryan H. Smith3, Chris R. Kelble1 and Peter B. Ortner1

1Cooperative Institute for Marine and Atmospheric Studies, U. of Miami, Miami, FL, USA 2Rosenstiel School of Marine and Atmospheric Science, U. of Miami, Miami, FL, USA 3NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL, USA

Oceanographic studies of Florida Bay and the connecting waters of the south Florida coastal region including the Florida Keys and the southwest Florida shelf have been underway since December 1995 for the purpose of describing and understanding the circulation processes on regional and subregional scales and the influence of remote sources of water mass intrusions. The study area of the NOAA-funded South Florida Program for long-term measurement of currents, temperature, salinity and bottom pressure with moored arrays and research vessel surveys is shown in Figure1.

The South Florida Coastal Oceanographic Database (SFCOD) is undertaken as part of NOAA's South Florida Ecosystem Research and Monitoring Program (a collaborative effort sponsored by NOAA's Coastal Ocean Program, in support of the Florida Keys National Marine Sanctuary), the Atlantic Oceanographic and Meteorological Laboratory (AOML) and the Rosenstiel School of Marine and Atmospheric Science (RSMAS). The purpose is to organize historical and ongoing data being collected from the South Florida coastal region into a user-friendly web accessed data base to enhance and encourage research efforts to better describe, understand and model the oceanographic processes, and their interactions and influence on water quality and living marine resources. The database (http://www.aoml.noaa.gov/sfros/database/) is organized by projects, which are searchable by data types: moored time series, shipboard, drifters, satellite imagery, and linked to relevant atmospheric and other coastal data sets such as coastal sea level and river discharge. To date SFCOD covers the 17 year period from April 1989 to April 2006, but it is an ongoing process and is updated following each new mooring deployment period and research cruise. The mooring data along with the ship track data contribute to the South Florida Regional Observing System (SF-ROS).

We present the South Florida Coastal Oceanographic Database structure and show recent applications of the data sets to better understand volume transports and water exchange between Florida Bay and adjacent coastal waters due to tidal motions and passage of 2004 hurricanes.

This database is currently under construction and constitutes an effort to compile and distribute oceanographic data from the mentioned projects in the region. Data contained herein may or may not be quality controlled or in a finalized form. These data are intended for general scientific interest.


138

Fig. 1. Mooring locations during the South Florida Program for time series measurement of oceanographic properties such as currents, temperature, salinity, bottom pressure, fluorescence and transmittance. Also shown are CMAN atmospheric stations and shipboard survey tracks.

Contact Information: Nelson Melo, Cooperative Institute for Marine and Atmospheric Studies, University of Miami; AOML, Physical Oceanography Division, 4301 Rickenbacker Causeway, Miami, FL 33149-1026, USA, Phone: 305-361-4329, Fax: 305-361-4329, Email: [email protected]


139

Variations in Carbon and Oxygen Stable Isotopes in the Otoliths of Four Species of Juvenile Snapper (Lutjanidae) in Florida Bay Anne B. Morgan1 and Trika L. Gerard2

1Cooperative Institute for Marine and Atmospheric Science, Rosenstiel School of Marine and Atmospheric Science, University of Miami, FL, USA

2NOAA-NMFS, Southeast Fisheries Science Center, Miami, FL, USA Various species of snapper in Florida Bay are crucial components of the ecosystem and the fishing economy. Recent studies have focused on the otoliths, or ear stones, of teleost fish such as snapper, exploring diverse applications for otolith research such as stock determination, migration, age and growth, environmental histories, and more. The present study examines the concentration of δ13C and δ18O stable isotopes in the otoliths of four snapper species found in Florida Bay. Carbon isotopes are determined by several, mostly metabolic factors, while oxygen isotopes reflect the ambient water conditions. The ultimate goal is to determine whether any of the four snapper species can be used as a proxy for another in future stable isotope projects in order to alleviate the difficulty of obtaining a substantial sample size. Interspecies and temporal analyses were performed on 263 samples taken over 5 years from 7 sites. Results were inconsistent, with the most promising comparison occurring between schoolmaster and gray snapper found in Northeast Florida Bay. Further research with more comprehensive data is necessary to draw a strong conclusion, but stable isotope projects involving snapper in Florida Bay should be species-specific to report any future findings with confidence. Contact Information: Anne B. Morgan, Cooperative Institute for Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA,Phone: 386.689.5855, Email: [email protected]

Trika L. Gerard, National Oceanic and Atmospheric Administration, Southeast Fisheries Science Center, 75 Virginia Beach Dr., Miami, FL, 33149, USA, Phone: 305.361.4246, Email: [email protected]


140

The Non-Native Red Rimmed Melania (Melanoides tuberculatus) in Biscayne Bay National Park, Florida, the Geographic Distribution and Potential for the Future James B. Murray1, G. Lynn Wingard1, Emily Phillips1 and William B. Schill2

1U.S.Geological Survey, Reston, VA, USA 2U.S. Geological Survey, Leetown Science Center, WV, USA

The non-native freshwater snail Melanoides tuberculatus (Family Thiaridae: common name Red-Rimmed Melania) was identified in Biscayne National Park (BNP) in 2003 by USGS researchers. A study began in 2004 to map the geographic range of M. tuberculatus, a gastropod native to Southeast Asia. The presence of M. tuberculatus is a significant concern in South Florida because it is an intermediate host for several human parasitic trematode worms including Clonorchis sinensis, Opisthorchis spp. (liver flukes) and Paragonimus westermani (lung fluke). It is an intermediate host for multiple parasites on waterfowl, for example, Philophthalmus megalurus affects the eyes of birds and Centrocestus formosanus, affects fish, crustaceans, and some mammals including humans. A study to determine the distribution, genetics, and salinity tolerance of M. tuberculatus began in 2007. One of the goals is to determine the likelihood of the marine waters of Biscayne Bay forming a barrier to the expansion of this snail into the estuarine and marine environments. Site surveys have found both living M. tuberculatus and shell debris near canal mouths and in the near shore areas in BNP from the southern boundary (south of the Turkey Point cooling ponds) to beyond the northernmost boundary (near the Cutler Ridge Power plant). Forty three distinct sites were selected for this survey encompassing canals and their entrances into the bay and nearshore locations along the western edge of BNP and radiating seaward. The canals that open into Biscayne Bay all have live M. tuberculatus in significant numbers and debris has been found along most of the western boundary of the park and in the connecting canals that lead into Park waters. The highest concentrations of both live and dead animals were in the vicinity of Black Point (BP) following the C-1 canal seaward into the bay. A transect was setup in 2004, at the Black Point canal opening into Biscayne Bay, to better quantify the population expansion at this site. Field surveys from 2004 through 2007 show that M. tuberculatus are becoming increasingly abundant at Black Point (Figure 1). The estimated numbers of M. tuberculatus per square meter (based on raw counts using three petit ponar samples) approaches 60,000/m2, in 2006 at the BP transect location 4 (TR4), an increase from 696/m2 in 2004, at approximately 1400 meters from shore. The numbers, at the seaward most point of the transect (TR6, approximately 2200 meters from shore) increased from 87/m2 in 2004 to 3826/m2 in 2006. This illustrates how rapidly this species is increasing its geographic/habitat range, and the level of concern that will be needed with discovery of the associated parasites. Two different approaches were used to determine the salinity resilience of M. tuberculatus: gradual salinity changes over the course of weeks that would duplicate climatic changes, and rapid salinity changes that duplicate tide and weather changes/cycles. Salinities were changed on a weekly basis starting at 5ppt dissolved salts with two end salinities that replicate high marine range (45ppt), and the mid range/estuarine (20-25ppt) salinities typically seen in BNP. A third system was maintained at the 5ppt dissolved salts as an experimental control. Thirty individuals were used in each system and daily observations were made to monitor population changes, temperature, and salinity. The snails in both the estuarine and the marine systems increased their population size by 300% to 400%, while the 5ppt system had no reproduction. The snails in the


141

higher saline waters were maintained at the high salinities (>45ppt?) for three months with no die-off. Juveniles grew at a steady rate with no apparent abnormalities. The rapid change (35-40ppt to 5-10ppt) salinity experiments had similar results with no fatalities. The snails retract into their shells and go into stasis for more than twenty four hours when initially stressed, so normal tide cycles have little affect. These initial results raise important questions about what affect the native populations will suffer. Population growth in M. tuberculatus is rapid due to a combination of parthenogenesis and live bearing young (the eggs are hatched and brood internally) reproductive strategies used by this animal. Genetic studies are underway to determine if this local group is becoming highly tolerant to salinity changes in comparison to other Florida populations. The presence of M. tuberculatus and its apparent ability to withstand broad ranges of salinity raises multiple concerns for BNP and the visitors that use the Park everyday. In addition, specimens both live and debris, have been collected in canals that terminate in Florida Bay and in the wilderness areas north and west of Flamingo in Everglades National Park. With increased tolerance to salinity, native species of animals will be affected and, as the populations and distribution of M. tuberculatus increase due to projected global climate changes the risk of parasite infection to humans, fish, shellfish, birds, and other animals will increase as the habitat range increases. Resource managers and the general public need to be aware of this non-native/invasive snail and take steps to monitor its host status and prevent its spread and additional introductions.

Figure 1 Raw counts of M. tuberculatus, live and dead, collected in 2004 and 2006 along a transect from Black Point. Black numbers are the actual counts retrieved from three bottom grab samples (using a petite ponar device) at each site. Red numbers represent estimates of the numbers of individuals per square meter based on the raw counts. Contact Information: James B. Murray, EESPT USGS, 12201 Sunrise Valley Dr., Reston, VA, 20192, USA, Phone: 703-648-6918, Fax: 703-648-6953, Email: [email protected]


142

Nutrient Limitation in Benthic Microalgae in Florida Bay Merrie Beth Neely and Gabriel A. Vargo

University of South Florida College of Marine Science, St. Petersburg, FL, USA Dissolved nutrients are commonly measured in the Bay, and to a lesser extent water column nutrient bioassays are performed. Sediment nutrient bioassays in the Bay are very rare. Dissolved nutrient availability in the water column arises dually from nutrient uptake/ assimilation and autochthonous/allochthonous supply. Benthic-pelagic coupling of these dual processes, combined with phytoplankton community composition and response rates further complicate relationships between nutrients and chlorophyll a standing stock in Florida Bay. I collected sediment from two locations in Florida Bay and transferred the benthic microalgal community into mescosms with a buried tubing nutrient delivery system. Filtered field water was added to the mesocosms to represent the water column, while the benthic microalgal community was essentially natural. Macroscopic grazers were removed. Inorganic nitrogen (N), phosphorus (P) and a combination of both were added to triplicate mescosms and compared to controls over a short time-course experiment for dissolved nutrient availability and chlorophyll concentration in the water column as well as benthic chlorophyll a concentration. Change in chlorophyll a standing stock was used as an indicator of nutrient limitation of the natural benthic microalgal community and in the filtered water column community. Dissolved P scarcity in the water column coincided with P limitation in benthic microalgae in Central Florida Bay, but not for the filtered water column phytoplankton community, which was N limited in the summer and P limited in the winter. Western Florida Bay was more complicated and was probably temperature limited during my experiment. More sediment mesocosm bioassays are necessary. Temporal and spatial trends in nutrient supply and availability in Florida Bay do not consistently support experimental bioassay findings of nutrient co-limitation in both the sediment and water column in this study, and in the water column in other studies. Co-limiting nutrients and short-term community response to nutrient limitation are not evident from dissolved nutrient availability or infrequent bioassays. My findings from these experiments suggest it would be perilous to assume the pelagic and benthic microalgal communities respond in unison to perceived nutrient limitation based upon dissolved nutrient availability. A synthesis of my research of benthic-pelagic coupling in Florida Bay, based upon field and laboratory experiments of benthic microalgae and sediment nutrient flux presented at previous meetings, will be provided. Contact Information: Merrie Beth Neely, Florida Department of Environmental Protection, 3900 Commonwealth Blvd., MS300, Tallahassee, FL, 32399-3000, USA, Phone: 850 413-7785, Fax: 850-414-7725, Email: [email protected]


143

Evaluating Alternative Plans for the Biscayne Bay Coastal Wetlands Project Patrick Pitts1, Rick Alleman2, Mark Shafer3, Kevin Wittman3 and Ernie Clarke3

1U.S. Fish and Wildlife Service, Vero Beach, Florida, USA 2South Florida Water Management District, West Palm Beach, Florida, USA 3U.S. Army Corps of Engineers, Jacksonville, Florida, USA

The Biscayne Bay Coastal Wetlands (BBCW) project is part of the Comprehensive Everglades Restoration Plan (CERP). The primary goal of the project is to improve the quality, quantity, timing and distribution of flows to restore and maintain desirable biological communities in Biscayne Bay, Biscayne Bay National Park, and adjacent coastal wetlands. The BBCW study area is in southeast Miami-Dade County in an area where coastal freshwater and saltwater wetlands have been fragmented and/or converted for agricultural and suburban development, and historic flows to Biscayne Bay have been altered by humans. The project was developed by the U.S. Army Corps of Engineers (USACE), South Florida Water Management District, National Park Service, U.S. Fish and Wildlife Service, Miami-Dade County Department of Environmental Resources Management, and other federal, state, tribal and local partners. USACE is the Federal sponsor for the project and regulations dictate how USACE ecosystem restoration and other Civil Works projects are formulated, evaluated and selected for implementation. Typically, alternative plans are developed for a given project and those plans are evaluated and compared using benefit-cost ratio analysis and net economic development values. Critical components to this analysis are the identification and quantification of ecosystem restoration outputs in measures that are comparable across alternatives. These outputs, generally referred to as Habitat Units (HU’s) for CERP decision making, are typically calculated utilizing habitat suitability models, such as the Habitat Evaluation Procedure or the Hydrogeomorphic Approach to Assessing Wetland Functions. However, none of the common evaluation methods were suitable for the BBCW project. For the BBCW project, the study team developed a unique tool called the Criteria Based Ecological Evaluation Matrix (CBEEM) to compare alternative restoration plans. The CBEEM was derived from a well documented method known as the Multi-Criteria Decision Making (MCDM) approach. MCDM is a holistic decision making tool utilizing measures and procedures that aim to combine multiple criteria, which can be either conflicting or supporting, and provides credence to investment decisions. Based on this approach, the CBEEM was developed by a multi-agency team of ecologists and scientists familiar with the study area and knowledgeable about the ecological stressors the BBCW project seeks to influence. This poster describes the CBEEM and provides examples of its output. CBEEM was developed to assess the relative ecological benefits and consequences of BBCW project alternatives to guide selection of the recommended restoration plan. CBEEM is a Microsoft (MS) Excel spreadsheet tool that utilizes hydrologic modeling results, management measure size and operation, and available hydrologic data to calculate a HU score for each alternative. CBEEM is used to evaluate ecological benefits for each of the three major ecological zones present within the project area separately using performance measures (PMs). The three ecological zones include the near shore bay estuarine zone, the saltwater or tidal wetlands zone, and the freshwater wetlands zone. Each PM addresses specific project objectives, relates to conceptual ecological models that have been developed for Biscayne Bay and the adjacent mangrove transition zone, and quantifies to the extent possible the ecological benefits


144

provided by the measure. The PMs include: (1) restoration of near shore salinity regime, (2) restoration of tidal wetland salinity regime, (3) reduction in harmful point source canal discharges, (4) potential freshwater rehydration, (5) reduction in nitrogen concentrations, (6) reduction in phosphorus loading to Biscayne Bay, (7) reduction in non-native vegetation, and (8) decompartmentalization of the wetlands and basins. The CBEEM evaluation is accomplished in four steps: (1) calculate PM output, (2) normalize PM output, (3) compute habitat quality index, and (4) apply the quality index to the spatial area that will be affected to yield HUs. PMs are quantified to the extent possible using model output, hydrologic data, project feature operation, and Geographic Information System data. Numeric targets for evaluation metrics were established whenever possible. For these metrics, the scores were converted to percent of target achieved to compare and contrast between and among evaluation metrics, and to normalize the output. Establishing targets for some metrics was not possible. In these cases, scores were normalized against the alternative with the highest score. Normalizing output allowed evaluation metrics to be combined to produce an ecological benefits index for each ecological zone. For this project, the scores from all the evaluation metrics applicable to a given ecological zone were simply averaged to provide a single index value for that zone (i.e., all PMs were equally weighted). The indices were then applied to the total spatial extent of each ecological zone (in acres) to produce HUs. Thus, HUs were provided separately for the near shore, saltwater wetlands, and freshwater wetlands zones. The Cost Effective/Incremental Cost Analysis was performed for each of the three ecological zones. Preliminary results show that certain PMs indicate significant differences in performance between project alternatives; other PMs indicate relatively little difference. However, when all PMs applicable to a given ecological zone are aggregated to provide an overall ecological index for that zone, sufficient differences in index values provide reasonable separation in alternative performance. Output from the CBEEM, including examples of PM and index scoring, will be provided in the poster presentation. While not specifically addressed in the alternative plan evaluation, sea level rise as a result of climate change will almost assuredly affect the project area. Anticipated sea level rise affects and possible management measures to address those affects will be included in the poster. Contact Information: Patrick A. Pitts, U.S. Fish and Wildlife Service, 1339 20th Street, Vero Beach, Florida, 32960, USA, Phone: 772-562-3909, Email: [email protected]


145

Geochemical and Nutrient Concentrations in the Florida Bay Groundwater René M. Price1, Jeremy C. Stalker1, Xavier Zapata-Rios1, Jean l. Jolicoeur2 and David T. Rudnick3

1Florida International University, Department of Earth Sciences and SERC, Miami, FL, USA 2Broward College, Fort Lauderdale, FL, USA 3South Florida Water Management District, West Palm Beach, FL, USA

INTRODUCTION Given concerns regarding the relationship of changing fresh water inputs to Florida Bay and the occurrence of algal blooms in the bay, it is important to gain a quantitative understanding of nutrient sources that can influence these blooms and how these sources may change in association with restoration efforts. Nutrients derived from groundwater sources constitute a major unknown for the Florida Bay. Both nitrogen (N) and phosphorus (P) inputs from the groundwater may be important, but P is of particular concern because much of the Bay’s productivity is P limited. Along the Everglades mainland, groundwater P concentrations were found to increase with salinity towards Florida Bay (Price et al., 2006). Given that groundwater wells installed in Florida Bay often have salinities greater than 35 psu, the objective of this investigation was to determine if this trend in increasing P concentration with salinity continued in the groundwater beneath Florida Bay. METHODS Groundwater, surface water, and porewater samples were collected at 7 sites in northeast Florida Bay (Figure 1) in September 2007 and March 2008. Prior to sampling of each well, they were purged of at least 3 wells volumes using a high flow pump. During purging, specific conductance, salinity, temperature, pH and dissolved oxygen were monitored until stable readings were obtained using Orion meters. Water samples were collected for total concentrations of phosphorus, nitrogen, and organic carbon. Water samples were also collected for dissolved concentrations of nitrite, nitrate, ammonium, phosphate. Water samples collected for total phosphorus and dissolved phosphate (soluble reactive phosphate) were collected in sterile bags that were first flushed with helium and then evacuated with a vacuum pump in an attempt to remove any exposure of the groundwater sample to atmospheric levels of oxygen. A filtered sample was also collected for chloride and sulfate, as well as for total alkalinity. Samples collected for dissolved concentrations were filtered through a 0.45 μm groundwater filter. Nutrient and geochemical parameters were determined at the SERC Water Quality Laboratory and Hydrogeochemistry Laboratory, respectively, at FIU. RESULTS During both sampling events, surface water salinity was lowest (<24 psu) at Little Madeira Bay and increased in a southeast direction across the bay to Key Largo were the salinity values exceeded 30 psu. The reverse was observed in the groundwater with salinity increasing to the north from Key Largo to the Everglades border. Hypersaline conditions (<42 psu) were observed in the groundwater at Little Madeira Bay. Porewater salinity was lowest at Nest Key (32 psu) in the center of the bay and highest at Duck Key (37 psu). Concentrations of TP, SRP and NH4

+ were higher in the groundwater as compared to the overlying surface water. TP in the surface water samples was often less than 0.15 μM, except for the surface water at the Key Largo Ranger Station that had the highest TP concentration of 0.37 μM (Table 2). The porewater at the KLRS also had the highest observed TP value of 4.91 μM.


146

The next highest value of TP was observed in the deep groundwater at the Bayside Well Cluster at a concentration of 4.06 μM. SRP of the surface waters varied from 0.01 to 0.62 μM with the highest concentrations often observed along the shoreline of Key Largo. In the porewater samples, SRP values were higher at concentrations ranging from 0.3 to 0.5 μM. Groundwater samples had the highest SRP values ranging from 0.2 to 2.9 μM. The highest SRP values were consistently obtained from a groundwater well located along the bayside of Key Largo. TOC in the porewater samples was higher than either the surface water or groundwater (Figure 6a) with values ranging from 930 to 1119 μM. Surface water TOC values ranged from 438 το 685 μM. Groundwater concentrations of TOC were slightly lower and ranged from 290 to 490 μM. The mean concentration of alkalinity in the surface water samples was 205 μM, versus 256 μM for the groundwaters (Figure 6b). DISCUSSION Geochemical and nutrient data from the Everglades mainland suggest that elevated concentrations of phosphorus in the groundwater is most likely attributable to water-rock interactions, such as calcium carbonate mineral dissolution or ion exchange (Price et al., 2006). To determine if carbonate mineral reactions could be responsible for the elevated P observed in the groundwater beneath Florida Bay, the major ion and field data was input to the geochemical model PHREEQC. The model results indicate that the surface waters of Florida Bay are highly saturated with respect to both calcite and aragonite. These results are expected as surface seawater is often supersaturated with respect to these minerals (Stumm and Morgan, 1996). Porewater samples were at equilibrium with respect to aragonite, and slightly supersaturated with respect to calcite. Most of the groundwater samples were near equilibrium to supersaturated with respect to calcite and aragonite. Only the groundwater from Little Madeira Bay was undersaturated with respect to both calcite and aragonite. References: Price, R. M, P.K. Swart, and J.W. Fourqurean. Coastal groundwater discharge - an additional source of phosphorus

for the oligotrophic wetlands of the Everglades. 2006. Hydrobiologia 569:23-36. Stumm, W. and Morgan, J.J. 1996. Aquatic Chemistry, Chemical Equilibria and Rates in Natural Waters, Third

Edition, John Wiley & Sons, New York, NY, 1022pp. Contact Information: René Price, Dept. of Earth Sciences and SERC, Florida International University, PC-344, 11200 SW 8th St., Miami, FL 33199, Phone: 305-348-3119, Fax: 305-348-3877, Email: [email protected]


147

Regional Patterns of Community Composition and Abundance of Seagrass-Associated Fish and Invertebrates in South Florida Estuaries Michael B. Robblee1, Joan A. Browder2, Andre Danielś1 and Robert M. Dorazio3

1U.S. Geological Survey, Miami, FL 2NOAA Fisheries, Miami, FL 3U.S, Geological Survey, Gainesville, FL

Restoration activities in the Everglades are expected to affect the quantity, timing, and distribution of freshwater inflows to South Florida’s estuaries with consequent changes to estuarine salinity regimes and benthic vegetation. We hypothesize that abundance and diversity of seagrass-associated fish and invertebrates in nearshore waters of South Florida will increase as the area of overlap of favorable salinity conditions with favorable seagrass/algal habitat increases. The South Florida Seagrass Fish and Invertebrate Assessment Network (FIAN) monitors seagrass-associated fish and invertebrate populations annually at 19 monitoring locations at the end of the dry and wet seasons, April/May and September/October, respectively. Monitoring locations are distributed among three regions in South Florida: Biscayne Bay, Florida Bay, and the southwest mangrove coast. The scale of FIAN affords the opportunity to view seagrass faunal communities in South Florida in relation to salinity and benthic habitat from a regional perspective, a perspective not previously available. At each of the 19 monitoring locations a sampling grid of 30, equally sized, hexagonal cells provides the base of the FIAN sampling design. A single randomly located 1-m2 throw-trap sample is collected from within each grid-cell, resulting in 30 samples from each location and 570 samples for each collection. Two collections are made each year, one near the end of the dry season (April/May) and one near the end of the wet season (September/October). Associated with each animal sample are measures of seagrass and algal habitat: a harvested sample for standing crop, density and blade metrics and Braun-Blanquet visual estimates of cover and abundance. Data obtained in this manner are well suited for statistical analysis as well as mapping and spatial interpolation. Hierarchical cluster analysis (Bray-Curtis similarity, complete linkage) was used to identify natural groupings of the 19 FIAN monitoring locations based on the similarities of their epibenthic community assemblages. In each of six FIAN collections (2005 to 2007) the FIAN monitoring locations comprising the southwest mangrove coast region separate as a cluster at similarities less than 20% from the Florida Bay and Biscayne Bay regions. The distinct mangrove-dominated southwest coast cluster is characterized by lower salinities, sparse benthic vegetation (little seagrass) and high turbidity. Among collections, clusters of monitoring locations in Florida Bay and Biscayne Bay, identifiable at similarities of about 50%, are generally consistent and encompass a gradient of seagrass canopy development; from high stature, diverse, and dense grass canopy, accompanied by deep sediments and low turbidities transitions to low stature, often monospecific, sparse grass canopy accompanied by shallow sediments and higher turbidities. Turtle grass, Thalassia testudinum, is the dominant seagrass in these regions, whereas shoal grass, Halodule wrightii, while generally sparse, is the seagrass observed at monitoring locations in the southwest coastal region. The Whitewater Bay fish and invertebrate communities are the most distinctive among the 19 FIAN monitoring locations. A map of the abundance of prominent species illustrates regional differences. The fauna observed in Florida Bay and Biscayne Bay regions are typical of shallow seagrass habitats in


148

south Florida. Patterns of abundance in these regions broadly reflect seagrass community development. The abundant and common species observed are grass canopy associates, such as the rainwater killifish, Lucania parva, the Gulf toadfish, Opsanus beta, the grass shrimp, Thor floridanus, pipefishes, etc. In contrast, these species are present in very low numbers at monitoring locations in the southwest coastal region. Lucania parva and Thor floridanus, the most abundant species observed in FIAN, are virtually absent from the southwest coastal monitoring locations while two common caridean shrimp, Periclimenes americanus P. longicaudatus, are relatively common there. The caridean shrimps Ogyrides alphaerotrus and O. hayi are found only in the southwest coastal region. A second commercially important penaeid shrimp, Rimapenaeus constrictus, the roughneck shrimp, is numerous seasonally only in monitoring locations bordering the Gulf of Mexico. All species, with the exception of the pink shrimp, Farfantepenaeus duorarum, are found in very low densities or are absent from the Whitewater Bay monitoring location.

The regional perspective provides invaluable insights; the uniqueness of the Whitewater Bay monitoring location is an example. Another case in point is the pink shrimp. The relationship of pink shrimp abundance with salinity may be more complex than suggested previously by laboratory and field studies where optimal growth and survivorship of juvenile pink shrimp occurs at salinities between 25 and 35 psu, declining sharply at lower and higher salinities. The pink shrimp is abundant in South Florida in the fall and is one of a very few abundant or common species observed in FIAN to date that are found in all regions. The pink shrimp is abundant in the southwest coast region, especially at the Whitewater Bay monitoring location, where benthic vegetation is sparse and salinities are typically low in the fall, <12 psu at the time of collection in FIAN. In contrast, in the fall pink shrimp are also abundant in western Florida Bay and Biscayne Bay, where the grass canopy is well developed and marine salinities (28-38 psu) typically prevail. Revealed at a regional scale this pattern does not fit expectations based on the laboratory-derived survival and growth curves for pink shrimp in relation to salinity. Contact Information: Michael B. Robblee, USGS/Everglades National Park, 40001 State Road 9336, Homestead, FL 33034, Phone: 305-242-7832, Fax: 305-242-7855, Email: [email protected]


149

Use of Habitat Suitability Index Modeling for Both Roseate Spoonbills (Ajaia ajaia) and American Crocodiles (Crocodylus acutus) in South Florida F. J. Mazzotti, 1, S. S. Romanach2, J. J. Lorenz3, K. L. Chartier1, M. S. Cherkiss1 and L. A. Brandt4

1University of Florida, Fort Lauderdale Research and Education Center, Davie, FL, USA 2US Geological Survey, Davie, FL, USA 3Audubon of Florida, Tavernier, FL, USA 4US Fish and Wildlife Service, Davie, FL, USA

Historically, Florida Bay experienced large volumes of fresh water as runoff from the Everglades, but development in South Florida led to a system of canals being constructed for human needs with the result of diverting fresh water away from many areas in the greater Everglades ecosystem, including Florida Bay. As a result, Florida Bay has experienced major changes in salinity, flora, and fauna, and experienced many species population declines. Projects outlined in CERP are designed to promote overland flow into Florida Bay through Taylor Slough and northeast Shark River Slough. The planned restoration projects will affect salinity and water depth both spatially and temporally. Roseate spoonbills (Ajaia ajaia) and American crocodiles (Crocodylus acutus) were selected for modeling because they are ecologically and recreationally important and have a well-established linkage to stressors (salinity and water depth) of management interest in South Florida. We use habitat suitability index (HSI) models to represent the degree to which a habitat could support a species or community. Habitat suitability index models were developed as an evaluation tool to aid in the assessment of acceptable ranges of salinity and water depth. In the case of spoonbills we focus on how these two factors relate to prey availability and abundance and distance to a nesting site. In the case of crocodiles we focus on how these two factors relate to prey production and distance nestlings travel from suitable nesting sites. Both models use a common base that uses various physical model outputs of salinity and water level to estimate the abundance and availability of a common prey base for both juvenile crocodiles and nesting adult spoonbills. Model outputs can be viewed with a data viewer that produces color maps of input and output data (salinity, water depth, prey abundance and availability, and spoonbill and crocodile HSI values) that can be animated through time. We also manipulate the inputs of water depth and salinity to demonstrate how changes in these parameters influence the success of these two indicator species. These forecasting models are intended to be the first part of an adaptive management approach, and are validated by monitoring programs to measure actual system response. Contact Information: Stephanie Romanach, US Geological Survey, 3205 College Ave, Davie, FL 33314, Phone: 754-264-6060, Email: [email protected]


150

Benthic Habitat Mapping in Biscayne National Park Benjamin I. Ruttenberg1, Andrea Atkinson1, Andy Estep1, Judd Patterson1, Matt Patterson1, Robert Waara1, Brian Witcher1 and Elsa Alvear2

1U.S. National Park Service, South Florida/Caribbean Network, Palmetto Bay, FL, USA 2Biscayne National Park, Homestead, FL, USA

The South Florida/Caribbean Inventory and Monitoring Network (SFCN) of the National Park Service is responsible for implementation of an ecosystem monitoring program to help park managers and scientists understand changes in key Vital Signs. Marine Benthic Communities is SFCN’s highest ranking vital sign and covers changes in shallow and deep coral reef ecosystems and seagrass communities and will include monitoring coral reef communities at five national parks ranging from 400 acres to 200 sq. miles. To implement an effective long-term monitoring program in any marine system, detailed benthic maps are necessary. One objective of this project is to create techniques to survey coral reefs for the purposes of habitat mapping, ecological monitoring, change detection, and event assessment (for example: bleaching, hurricanes, disease outbreaks). These maps serve multiple purposes, such as identifying areas of focal habitat, facilitating ecological monitoring, and event assessment (e.g. bleaching, hurricanes, disease outbreaks). In Biscayne National Park, an effort is underway to create a detailed benthic habitat map of the entire seaward portion of the park, include all submerged areas from the keys that straddle the middle of the park to the 60’ depth contour that makes up the eastern boundary of the park. Partners include SFCN scientists, staff from BISC, and the Florida Wildlife Research Institute (FWRI) of the Florida Fish and Wildlife Conservation Commission (FWC). An initial benthic habitat map was generated by combining data from high resolution aerial photography and HawkEye Mk II LiDAR (Light Detection and Ranging). The aerial photography data have 1 foot resolution, and the lidar data are accurate to 5 meter horizontal resolution and 50 cm vertical (i.e. depth) resolution. The photointerpretation for the map was completed in October 2008. During fall 2008, SFCN staff and BISC staff conducted an intensive accuracy assessment of the benthic habitat map. We surveyed approximately 30 randomly generated points for each habitat category or subcategory, classifying each point with a number of attributes. First, points were classified as either unconsolidated sediment (i.e. softbottom) or coral reef/hardbottom. Softbottom sites were further classified as sand, mud, seagrass, or algal dominated. Hardbottom sites were further classified as spur and groove, individual patch reef, aggregated patch reef, aggregate reef, scattered coral/rock in unconsolidated sediment, pavement, or reef rubble. Results show that the benthic habitat map for BISC is highly accurate, and can be used to identify areas of appropriate habitat for SFCN’s long term coral monitoring program. We hope to complete the process of identifying and installing permanent monitoring sites within BISC by late spring 2009. Contact Information: Benjamin I. Ruttenberg, South Florida/Caribbean Network, National Park Service, 18001 Old Cutler Rd Suite 419, Palmetto Bay, FL 33157, USA, Phone: 305-252-0347, Fax: 305-253-0463, Email: [email protected]


151

Determining Spatial and Temporal Inputs of Freshwater, Including Groundwater Discharge, to a Subtropical Estuary Using Geochemical Tracers, Biscayne Bay, South Florida Jeremy C. Stalker1, René M. Price2 and Peter K. Swart3

1Department of Earth Sciences, Florida International University 2Department of Earth Sciences and the SERC, Florida International University 3Marine Geology and Geophysics, RSMAS, University of Miami

Introduction The timing and sources of freshwater delivery into an estuarine system affects not only the water quality (Caccia et al. 2007, Younger, 1996) but also the health, diversity and distribution of estuarine species such as seagrasses and juvenile fish (Rutkowski et al., 1999). Fresh surface water and precipitation are suggested to be the dominant sources of freshwater for most estuarine systems while submarine groundwater discharge (SGD) has largely been ignored due, in part, to the difficulty of quantifying it. The estuary of Biscayne Bay receives freshwater from precipitation, canal discharge, and fresh SGD. The proportions and spatial and temporal distribution of these inputs is still poorly constrained on a bay wide scale. The objective of this study was to differentiate these sources of freshwater geochemically, using stable isotopes of oxygen and hydrogen, and Sr2+/Ca2+ ratios. Methods Surface water samples were collected on a monthly basis from July 2004-July2006 from 25 surface water stations in Biscayne Bay in conjunction with Florida International University’s (FIU) Southeast Environmental Research Center (SERC) water quality monitoring program. In addition ten canals that are the dominant contributors of freshwater discharge into Biscayne Bay and 12 fresh groundwater wells were also sampled monthly. Prior to sampling, the groundwater wells were purged of at least 3 standing well volumes. Furthermore, rainfall samples were collected at two stations: one at the north end of Biscayne Bay at RSMAS and the other near the southern end of Biscayne Bay at the headquarters of Biscayne National Park (BNP). Rainfall was collected and combined for composite monthly samples. Salinity was recorded for each sample using an YSI multi-probe. Stable isotope and cation analysis were completed at the Stable Isotope Lab at the University of Miami Rosenstiel School of Marine and Atmospheric Sciences (RSMAS). Results These stable isotope and cation results were used in three separate mixing models and then combined to quantify the magnitude and timing of the fresh water inputs to the estuary. Fresh groundwater had an isotopic signature (δ18O = -2.66 ‰, δD, -7.60 ‰) similar to rainfall (δ18O = --2.86‰, δ D =-4.78 ‰). Canal water had a heavy isotopic signature (δ18O = -0.46 ‰, δ D = -2.48 ‰) due to evaporation. This made it possible to use stable isotopes of oxygen and hydrogen to separate canal water from precipitation and groundwater as a source of freshwater into the bay. A second model using Sr2+/Ca2+ ratios was developed to discern fresh groundwater inputs from precipitation inputs. When combined these models showed a freshwater input ratio of canal input-precipitation-groundwater of 30%-60%-10% in the wet season and 40%-55%-5% in the dry season with an error of 21%. For a bay wide water budget that includes saltwater and freshwater mixing, fresh groundwater accounts for 2% of the total water input to Biscayne Bay.


152

Discussion Spatially, the isotope modeling results indicate the freshwater inputs to Biscayne Bay are dominated by the canal systems (surface water) near the western shoreline, while areas further east and closer to the ocean inputs precipitation is dominant. This spatial relationship of precipitation influence growing away from the mainland is similar to the results from studies on freshwater influence in Florida bay (Swart et al, 2003). The Sr2+/Ca2+ modeling results suggest an influence of groundwater inputs on the western shoreline of the bay that quickly dissipates to the east. The groundwater signature is higher in the wet season and extends into the northern narrow portion of the bay, while in the dry season the overall signature is limited to the central western portions of the bay. Temporally, in the wet season precipitation dominates (60% of total) freshwater inputs into the bay. While in the dry season canal water (40%) and precipitation (55%), given the modeling error, are roughly equivalent in influence. This seasonal difference should be partially expected as precipitation amounts are much higher in the bay during the wet season, and canal structures generally remain closed to maintain high groundwater levels for the dry season and are opened only in times of expected extreme rain events such as tropical cyclones. Reversely, in the dry season, the precipitation is much lower and the discharges from the canal systems become more important to salinity variation. Groundwater doubles in influence from 5% to10% from the dry to the wet season; this may be in part to the overall higher terrestrial groundwater levels in the wet season, while the combined error of the models (21%) is higher than the input of groundwater, the geochemical model that directly estimates groundwater influence has a error of only 1%. While yearly groundwater input percentages for the entire bay are low compared to the other sources of freshwater, monthly groundwater input percentages can account for upwards of 60% of freshwater input at sites near the western shoreline. References: Caccia, V. G., Boyer, J. N. (2007). A Nutrient Loading Budget for Biscayne Bay, Florida. Marine Pollution Bulletin,

Vol. 54, pp. 994-1008. Younger, P. L., (1996). Submarine groundwater discharge. Nature, 382:121-122 Rutkowski, C.M., Burrnet, W.C., Iverson, R.L., and Chanton, J.P., (1999). The Effect ot groundwater Seepage on

Nutrient Delivery and Seagrass Distribution in the Gulf of Mexico. Estuaries, Vo. 22. pp.1033-1040. Swart, P.K., Price R.M. (2002) Origin of Salinity Variations in Florida Bay, Limnology and Oceanography, 47,

1234-1241. Contact Information: Jeremy Stalker, Department of Earth Sciences, Florida International University, PC 344, 11200, SW 8th St., Miami, FL. 33199, USA, Phone: 305-978-3232, Email: [email protected]


153

Enhancing and Combining Complex Numerical Models of Coastal Southern Florida Eric Swain, Melinda Lohmann and Jeremy Decker

U.S. Geological Survey, Florida Integrated Science Center, Fort Lauderdale, FL, USA A coupled hydrodynamic surface- and ground-water model code has been used in multiple applications to represent the hydrology of southern Florida, including the coastal Florida Bay area. The coupled code is referred to as Flow and Transport in a Linked Overland/Aquifer Density-Dependent System (FTLOADDS). Applications of the FTLOADDS code have been used to evaluate potential changes to the hydrologic system caused by climatic change or proposed restoration initiatives. Linking FTLOADDS to regional, offshore, and ecological models has increased the usage and applicability of the code. Future uses require new capabilities and connections to address new questions and situations. The advanced capabilities of FTLOADDS are partly due to its origin as two separate codes used to model two-dimensional hydrodynamic surface-water flow and transport and three-dimensional ground-water flow and transport. The coupling of two preexisting model codes allows for broad compatibility with existing model developments and has the advantage of algorithms that have already been established. To correctly model the complex hydrology in southern Florida, however, development beyond model coupling has been necessary. Code enhancements include representation of salinity transport, rainfall and evapotranspiration, heat transport, and wind sheltering, as well as an improved representation of frictional resistance, surface-water wetting and drying, and surface-water control structures. Other recent developments that utilize FTLOADDS include programs that interface with regional and offshore models, and optimization techniques to design water-management schemes with the model. As a result of this long-term development, FTLOADDS can accurately represent a variety of coastal areas, conditions, and parameters of relevance to southern Florida. Three FTLOADDS applications cover the coastal areas of southern Florida, from the Ten Thousand Islands region on the southwestern coast to Biscayne Bay on the southeastern coast. The application to the Everglades National Park area is referred to as to Tides and Inflows in the Mangroves of the Everglades (TIME) application (Wang and others, 2007). This model incorporates salinity transport as well as improved representations of evapotranspiration and heat transport. TIME has been used to evaluate several CERP restoration scenarios by using input from the regional South Florida Water Management Model. The heat transport capabilities were initially developed for application to the Ten Thousand Islands area, where temperature prediction is important to investigate the effects of hydrologic restoration changes on manatee habitats. Applying heat transport to all of the FTLOADDS applications facilitates the study of a large range of hydrologic effects on biologic factors. Proposed restoration scenarios outline several alternative modifications to the L-31N and C-111 canals, shown in figure 1, to retain more water in the Everglades. These modifications range from blocking leakage under the canals during part of the year, to eliminating sections of the canal completely, with the objective of increasing freshwater flows into Florida Bay. The L-31N/C-111 canal is the boundary between the TIME area and the recently developed model application to the Biscayne Bay coastal area (Wolfert-Lohmann and others, 2008). The USGS has linked these two applications to create the Biscayne and Southern Everglades Coastal Transport (BISECT) application (fig. 1), which determines how canals affect ground-water


154

movement in and out of Everglades National Park. The BISECT application will allow the assessment of the current management system's effects on the ground water in the South Florida region, estimate the quantity of ground water moved, and delineate the locations to which the water is transported. The model can then be used to simulate alternate CERP restoration scenarios and evaluate how canal modifications affect the ground water quantity and distribution. Because the FTLOADDS code is used, the BISECT application will also be able to predict surface-water discharge, coastal freshwater exchange, water level, salinity, and temperature.

L-31N

C-111

Figure 1. -- BISECT model area and C-111/L-31N canal system.

References: Wolfert-Lohmann, M.A., Langevin, C.D., Jones, S.A., Reich, C.S., Wingard, G.L., Kuffner, I.B., and Cunningham,

K.J., 2008, U.S. Geological Survey Science Support Strategy for Biscayne National Park and Surrounding Areas in Southeastern Florida: U.S. Geological Survey Open-File Report 2007-1288, 47 p.

Wang, J, D., Swain, E.D., Wolfert, M.A., Langevin, C.D., James, D.E., and Telis, P.A., 2007, Applications of Flow and Transport in a Linked Overland/Aquifer Density Dependent System (FTLOADDS) to Simulate Flow, Salinity, and Surface-Water Stage in the Southern Everglades, Florida: U.S. Geological Survey Scientific Investigations Report 2007-5010, 89 p.

Contact Information: Eric Swain, U.S. Geological Survey, Florida Integrated Science Center, 3110 SW 9th Avenue, Fort Lauderdale, FL, 33315, USA, Phone: 954-377-5925, Fax: 954-377-5901, Email: [email protected]


155

Examining Submarine Groundwater Discharge into Florida Bay Using 222Rn and Continuous Resistivity Profiling Peter W. Swarzenski1, Chris Reich2 and David Rudnick3

1U.S. Geological Survey, Santa Cruz, CA 2U.S. Geological Survey, St. Petersburg, FL 3South Florida Water Management District, West Palm Beach, FL

Submarine groundwater discharge (SGD) estimates into Florida Bay remain one of the least understood components of a regional water budget. To quantify the magnitude and seasonality of SGD into upper Florida Bay, research activities included the use of the natural geochemical tracer 222Rn to examine potential SGD hotspots (222Rn surveys) and to quantify total (saline + fresh water component) SGD rates at select sites within the bay (222Rn time-series). The second research component utilized marine continuous resistivity profiling (CRP) surveys to examine the subsurface salinity structure within Florida Bay sediments. Maps of the 222Rn distribution within our study site in Florida Bay were obtained from a flow-through system installed on a small boat that consisted of a DGPS (with depth), a calibrated YSI CTD, and a submersible pump (z = 0.5 m) that continuously fed water into an air / water exchanger that was plumbed simultaneously into four RAD7 222Rn air monitors. To obtain local advective groundwater flux estimates, 222Rn time-series experiments were conducted at strategic sites across hydrologic and geologic gradients within our study site. Time-series 222Rn measurements were conducted for 3-4 days across several tidal excursions. Radon was also measured in the air during each sampling campaign by a dedicated RAD7. We obtained groundwater discharge information by setting up a 222Rn mass balance that accounted for lateral and horizontal exchange and an appropriate groundwater 222Rn endmember activity. In addition to the radon measurements, we also ran continuous resistivity profiles (CRP) within our study site. This system consisted of an AGI SuperSting 8 channel receiver attached to a streamer cable that has 2 current (A,B) electrodes and 9 potential electrodes spaced 10m apart. A separate DGPS continuously sent position information to the SuperSting. Results indicate that the 222Rn maps provide a useful gauge of relative groundwater discharge into Florida Bay. The 222Rn time-series measurements provide a reasonable estimate of site specific total (saline and fresh) groundwater discharge, and the saline nature of the shallow groundwater underneath our study site, as evidenced by CPR results, indicate that most of this discharge must be recycled sea water. The CRP data show some interesting trends that appear to be corroborated with geologic and hydrologic observations. For example, some of the highest resistivity (electrical conductivity-1) values were recorded where one would expect a slight subsurface freshening (e.g., bayside Key Largo, C111 canal). Contact Information: Peter W. Swarzenski, U.S. Geological Survey, Pacific Science Center, 400 Natural Bridges Drive, Santa Cruz, CA 95060, Phone: 831-427-4729, Fax: 831-427-4709, Email: [email protected]


156

Diatom-Based Inferences of Environmental Change in Florida Bay and Adjacent Coastal Wetlands of South Florida A. Wachnicka1,2 and E. Gaiser3,2

1Department of Earth Sciences, Florida International University, Miami, FL, USA 2Southeast Environmental Research Center, Florida International University, Miami, FL, USA 3Department of Biological Sciences, Florida International University, Miami, FL, USA

The spatial and temporal distribution of diatom assemblages in surface sediments, on the most dominant macrophytes, and in the water column at 38 sites located in the freshwater Everglades, coastal mangroves, and Florida Bay was examined in order to develop paleoenvironmental prediction models for the region. Assemblages sorted along strong salinity gradient were grouped accordingly into 3 distinct spatial clusters. Spatial differences exceeded temporal, although wet and dry season differences in assemblage composition were notable in coastal mangrove and Florida Bay sites. Epiphytic assemblages differed from planktonic and epipelic, but more significant overlap between the latter two indicated a high degree of mixing in the shallow waters of Florida Bay. The relationship between each taxon and salinity was determined and incorporated into multi-taxon prediction model using weighted averaging partial least squares regression. Salinity was the most influential variable among measured water parameters, resulting in a highly resolved prediction model that can be used to calibrate sediment assemblages and infer ecological consequences of changes in climate and water management in the Everglades drainage. A discriminant function analysis showed that diatom assemblages can also be used to reconstruct the availability of common benthic substrata, a novel and useful addition to the numerical water quality predictions. The diatom-based prediction models for salinity and habitat-type were used to environmentally calibrate diatom records in chronologically calibrated sediment core collected at Bob Allen site in Florida Bay. In our analyses we focused on the last ~150 years of record (55cm) to determine the magnitude of salinity, vegetation cover, and habitat-type alteration resulting from anthropogenic change in the South Florida landscape. Habitat inferences suggest persistent fluctuations between macrophytes- and plankton-dominated states. Sporadic appearance of freshwater taxa among typical marine diatom species in the core indicates influence by variability in freshwater supply. The core has been divided into two distinct major bio-zones and few sub-zones using stratigraphically constrained cluster analysis. Each of the clusters contains distinct diatom assemblages which are associated with different habitat types. Zone 1 represents period after 1960 till 2002 while zone 2 represents time between 1843 and 1960. Diatom-based salinity model indicates that there was one particularly big inflow of freshwater in zone 1 around 1970 and at least two in upper part of zone 2 around 1948 and 1899. The diatom assemblages in lower part of zone 2 indicate multiple increases in freshwater supply between 1854 and 1877. The appearance of distinct diatom assemblages after 1960 suggests that the hydrological regime at Bob Allen site was probably affected by the construction of major canals and levees in South Florida in early 1900’s but presence of mixed fresh and marine diatom assemblages throughout the core indicate that the seasonal and annual changes in climatic conditions played dominant role in influencing salinity conditions at the site. Contact Information: A. Wachnicka, Southeast Environmental Research Center, Florida International University, 11200 SW 8th Street, Miami, FL, 33199, USA, Phone: 305-348-7286, Fax: 305-348-4096, Email: [email protected]


157

Effects of Habitat Complexity and Nutrient Enrichment on Epifauna Abundance and Diversity in a Florida Bay Seagrass System C. A. Weaver1, A. R. Armitage1 and J. W. Fourqurean2

1Department of Ecosystem Science and Management, Texas A&M University, College Station, TX, USA 2Department of Biological Sciences, Florida International University, Miami, FL, USA

Nutrient enrichment studies over the last five years have determined that much of the benthic primary producer community in Florida Bay is phosphorus (P) limited. Emergent trends suggested that P enrichment can also dramatically alter the structural complexity of the benthic community by changing species composition and plant morphology. Changes in the plant infrastructure can alter the function of the habitat for epifaunal refuge. Previous work suggests that faunal abundance, biomass, and species composition increase following nutrient enrichment, but the mechanisms of those alterations are unknown. Enrichment causes increases or shifts in epiphytic microalgal composition, which can alter food quality and quantity for grazing epifauna. Alternatively, increased structural complexity in the macrophyte (seagrass, macroalgae) community may increase the refuge value of the habitat for epifaunal organisms. We used artificial seagrass canopies to explicitly examine the role of epiphyte characteristics, nutrient supply, and structural complexity on epifaunal abundance, species composition, and trophic relationships. We constructed 40 1-m2 artificial seagrass units (ASU) by attaching green polypropylene ribbon to plastic mesh. Ribbon blade morphometrics and shoot densities chosen for ASUs were based on surveys of Thalassia testudinum and Halodule wrightii collected between November 2004 and April 2006 at high and low P-limited sites in Florida Bay. Two ASU canopy treatments were utilized: dense (total shoot density of 1,250; 250 wide T. testudinum and 1,000 H. wrightii ribbon shoots) and sparse (560 narrow T. testudinum ribbon shoots). Each shoot, for both treatments, consisted of three ribbon leaves. Leaf area index (m2 leaf area/m2) for dense and sparse canopy treatments was 2.51 and 1.34, respectively. ASUs were deployed at two sites in Florida Bay: an eastern Bay, severely P-limited site with sparse seagrass beds (Duck Key) and a west-central Bay site with moderate to weak P limitation and dense seagrass beds (Nine Mile Bank). At each site, aboveground vegetation was clipped to the substrate and 20 ASUs (10 dense and 10 sparse) were secured in place with metal pins. Slow-release nitrogen and phosphorus fertilizers were added to half of the ASUs, forming four experimental treatments: dense enriched, dense unenriched, sparse enriched, and sparse unenriched. After three months, we conducted Braun Blanquet (BB) surveys of plant and benthic macroorganism abundance. Epiphytes on artificial grass were collected for biomass, pigment, and stable isotope analyses. Epifauna were collected with a diver-held suction sampler for enumeration, identification, biomass, and stable isotope analyses. Microalgal mats occurred at Duck Key, the severely P-limited site, and were significantly more abundant in enriched treatments (mean BB score 1.65) relative to unenriched plots (mean BB score 0.05). There were no visible microalgal mats present in enriched or unenriched treatment plots at Nine Mile Bank. The algal mats may be composed of either diatoms or cyanobacteria; pigment analyses are planned to confirm microalgal composition. Macroalgal species grew into the ASUs at both Duck Key and Nine Mile Bank, though there were no significant differences in abundance between nutrient and canopy treatments at either


158

site. Nine Mile Bank plots had greater macroalgal species richness (n=6) compared to Duck Key (n=5). However, Duck Key had significantly higher overall macroalgal abundance (mean BB score 0.33) than Nine Mile Bank (mean BB score 0.17). Live T. testudinum also grew into ASUs at both sites. There was no significant difference in regrowth between nutrient and canopy treatments, but there was substantially higher live T. testudinum cover at Nine Mile Bank (mean BB score 3.0) than at Duck Key (mean BB score 0.83). H. wrightii was present in one plot (dense unenriched) at Nine Mile Bank and had a BB score of 1.0. Initial observations suggested an increase in epifaunal species richness and abundance in enriched ASUs at Duck Key. No obvious difference in species richness was observed between enriched and unenriched plots at Nine Mile Bank. Further analyses will enumerate and quantify biomass of epifaunal species captured in the ASUs. Stable isotope analyses will also be conducted to investigate potential trophic links between epifauna and epiphytes, microalgae, macroalgae, and live and detrital seagrass leaves collected in each ASU. Nutrient enrichment in previous experiments, especially at P-limited sites, led to changes in seagrass species composition and was thought to potentially change the refuge value for epifauna. Our initial findings suggest that nutrient enrichment has a stronger effect on epifauna richness, abundance, and density than canopy complexity. In this system, habitat complexity and refuge value may have a smaller impact on epifaunal populations than we originally predicted. The observed increase of epifauna diversity in enriched treatments could possibly be a trophic response to the significant rise in microalgal mat abundance. Determining if such a trophic link exists will improve our understanding of grazing epifauna’s role in reducing microalgal proliferations caused by natural or anthropogenic nutrient enrichment in Florida Bay. Contact Information: C. A. Weaver, Department of Ecosystem Science and Management, Texas A&M University, 2138 TAMU, College Station, TX 77843-2138, USA, Phone: 979-845-4468, Fax: 979-845-6430, Email: [email protected]


159

Understanding Ecosystem-Scale Connectivity: Methods to Track Fish from Open-Ocean to Nursery Habitats to Adjacent Reefs and Back Again S. Whitcraft1, J. Lamkin2, T. Gerard2 and E. Malca1

1Cooperative Institute for Marine & Atmospheric Science, University of Miami, Miami FL, USA 2NOAA Southeast Fisheries Science Center, Miami FL, USA

We are a multi-disciplinary team of scientists dedicated to excellence in early life history research to support applied fisheries management and habitat conservation in the Southeast Atlantic, Gulf of Mexico, and Caribbean ecosystems. To that end, we study the dynamics of how fish species use a variety of habitats during their life-cycle. For example, adult gray snappers (Lutjanus griseus) tend to spawn in deeper coastal waters, usually in association with coral reefs or hard-bottom substrate while coastal mangroves provide the intermediate juvenile habitat for gray snappers that recruit to seagrass beds. To study spawning and larval transport in pelagic waters we conduct large-scale survey cruises that sample, quantify, map, and model the distribution of specific fisheries species. To study smaller-scale estuarine and inshore habitat-use and movements of snappers we use otolith micro-chemistry and acoustic telemetry to determine site fidelity and habitat requirements. Understanding this dynamic ecosystem connectivity is vital to coastal habitat conservation planning and fisheries management. Contact Information: S. Whitcraft, Cooperative Institute for Marine & Atmospheric Science, University of Miami, NOAA-SEFSC, 75 Virginia Beach Drive, Miami FL 33149, USA, Phone: 305-361-4570, Fax: 305-361-4478, Email: [email protected]


160

Verification of a Molluscan Dataset for Paleosalinity Estimation Using Modern Analogues: A Tool for Restoration of South Florida’s Estuaries G. Lynn Wingard1 and Joel W. Hudley2

1U.S. Geological Survey, Reston, VA, USA 2University of North Carolina, Chapel Hill, NC, USA

Development of performance measures and salinity targets for the southern estuaries, including Florida Bay, Biscayne Bay, and the southwest coastal area of Everglades National Park, requires an understanding of historical, pre-drainage salinity patterns. Salinity patterns derived from faunal assemblage analyses of sediment cores collected in the southern estuaries have been used to establish pre-1900 temporal and spatial distribution of key salinity regimes (mesohaline, polyhaline, etc.) within the estuaries. These faunal assemblage analyses have been coupled with linear regression models based on observed hydrologic and meteorological patterns in the modern ecosystem to derive historical stage and flow in the Everglades and salinity in Florida Bay (Marshall et al., this volume). The paleoecologic data derived from the assemblage analyses, however, are semi-quantitative, and provide a simple snapshot for a section of core that may cover many decades. For example, the polyhaline salinity zone utilized for the Whipray Basin regression model discussed in Marshall et al. (this volume), spans approximately 60 years from 1893 to 1953. These data do not illustrate the subtle variations in assemblages that may be indicative of salinity fluctuations within the broader salinity regimes. In addition, many species present in the cores can tolerate a wide range of salinities and therefore interpretation of the salinity regime is not straight-forward if key indicator species are not present. In order to address these challenges and provide robust paleosalinity estimates with confidence levels, we developed a cumulative-weighted percent (CWP) salinity function based on modern-analogue molluscan data collected throughout the southern estuaries of the Everglades ecosystem. The basis of the CWP method is similar to established methodologies in paleoceanography for deriving sea surface temperature estimates (see for example, Imbrie and Kipp, 1971; Hutson, 1979; Dowsett et al., 2005). Modern data on molluscan distribution and salinity preferences from over 550 individual records (available at http://sofia.usgs.gov/ exchange/flaecohist/) were compiled and after univariate statistical analysis reduced to the modern analogue set consisting of 391 records and 55 species of mollusks. This analogue data set was then used to derive the CWP function for a modern test set consisting of 35 2-cm core-top samples from eight sites located near water quality monitoring stations. The resulting CWP value for each modern sample was then compared to averaged salinity values from the water monitoring stations over different periods of time. The resulting correlation coefficients are shown in Table 1. These results indicate that the modern molluscan analogue data set and the CWP method provide an accurate means of predicting salinity. The lowest correlation values (~0.5) are between observed salinity data averaged for less than 6 months and the CWP estimates, and the highest correlations are for 24 months or more. These values indicate that 2-cm samples in cores taken to derive historical salinity correspond to ~2-year salinity patterns with a correlation coefficient of 0.8 to 0.9 (1.0 is perfect correlation). This method will allow more detailed analyses of paleosalinity patterns beyond broad categorizations of salinity regimes (eg. polyhaline) and


161

provide a means of overcoming problems associated with analyzing fauna tolerant of a broad range of salinity conditions. Table 1: Correlation Coefficient comparing hydrologic station data averaged over different time periods to the results of the CWP calculations on the modern samples. Two different calibration datasets were used: 1) full calibration data set (FULL), which includes any species with environmental information, and 2) culled data set (CONFID), which includes only species with ≥10 observations and confidence level of ≥95.0%. The two different combinations of molluscan preservation categories tested were: 1) pristine (intact with luster/color) and broken mollusks (P + B); 2) pristine, broken, and whole (intact but lacking luster/color) mollusks (P + B + W).

Cummulative Weighted Percent

Analyses Correlation Coefficient between Average Hydrologic Station Salinity

and CWP Calculated Salinity

Sta

tistic

al M

easu

re

Cal

ibra

tion

Dat

a S

et

Pre

serv

atio

n C

ateg

orie

s

1 Month

3 Months

6 Months

12 Months

18 Months

24 Months

30 Months

36 Months

Mean FULL P + B 0.5734 0.5288 0.6367 0.7272 0.7847 0.8468 0.8575 0.8746

CONFID P + B 0.5499 0.5335 0.6631 0.7605 0.7890 0.8425 0.8554 0.8653 FULL P + B + W 0.6218 0.5619 0.6659 0.7567 0.8240 0.8989 0.8909 0.9085

CONFID P + B + W 0.5925 0.5776 0.7053 0.7884 0.8285 0.8838 0.8869 0.8938 Median

FULL P + B 0.5382 0.4965 0.6290 0.7506 0.8121 0.8655 0.8644 0.8805 CONFID P + B 0.5313 0.5149 0.6462 0.7598 0.7997 0.8437 0.8376 0.8495

FULL P + B + W 0.6073 0.5529 0.6711 0.7740 0.8407 0.9065 0.8899 0.9069 CONFID P + B + W 0.5840 0.5659 0.6887 0.7777 0.8309 0.8804 0.8677 0.8783

References: Dowset, H.J., Chandler, M.A., Cronin, T.M., and Dwyer, G.S. 2005. Middle Pliocene sea surface temperature and

variability: Paleoceanography, v. 20, doi:10.1029/2005PA001133, 2005. Hutson, W.H. 1979. The Agulhas current during the Late Pleistocene: analysis of modern faunal analogs: Science,

v. 207, n. 4426, p. 64-66. Imbrie, J. and Kipp, N.G. 1971. A new micropaleontological method for quantitative paleoclimatology:

application to a Late Pleistocene Caribbean core: In “The Late Cenozoic Glacial Ages, K.K. Turekian, ed., p. 71-181. Yale Univ. Press: New Haven CT.

Contact Information: G. Lynn Wingard, Eastern Earth Surface Processes Team, U.S. Geological Survey, MS 926A National Center, 12201 Sunrise Valley Drive, Reston, VA, 20192, USA, Phone: 703-648-5352, Fax: 703-648-6953, Email: [email protected]


162

Power Analysis of Water Quality and Seagrass Monitoring in Caloosahatchee Estuary Deo Chimba and Jing-Yea Yang

Stanley Consultants Inc., West Palm Beach, Florida The goal of this paper is to determine the ability of the existing monitoring program to detect environmental change using a power analysis statistical technique for the Caloosahatchee River and Estuary (CRE). The monitoring program of interest for this project is for Water Quality (WQ) and Seagrass density (i.e. number of shoots/m2) This monitoring program constitutes example of the major type of ongoing environmental monitoring. The intention of the monitoring program is to detect temporal trends. Hence, the Power Analysis will focus on detecting change in the long term means of the selected water quality and seagrass parameters.

OBJECTIVES The first objective of this project is to conduct a statistical Power Analysis on the existing monitoring program in CRE for their respective water quality and seagrass parameters. The following questions shall be addressed at seasonal, quarterly, monthly, semi-monthly (i.e. every 14 days), weekly and daily frequencies:

1. What is the percent probability of detecting change at the above frequencies vs. the percent change in the long-term mean?

2. What is the percent probability of detecting change vs. years of monitoring at the above frequencies?

3. What is the minimum detectable change (percentage) vs. years of monitoring at the above frequencies?

4. What is the percent coefficient of variation vs. years of monitoring at the above frequencies?

The second objective of this project is to provide managers with simple tables and graphics that show the time it will take to detect change as a function of the magnitude of change and the frequency of sampling. These visual tools reflect the results of answering the above four power analysis questions. Based on the power analysis at each station and parameter, the following conclusions can be made:

1. Monthly sampling produced the highest power percentage of detecting change for salinity, seagrass density and water quality data sampling.

2. Minimum Detectable Change (MDC%) is the highest at seasonal sampling followed by quarterly, daily, monthly, bi-weekly and weekly in that order for salinity data sampling.

3. Minimum Detectable Change (MDC%) is the highest at seasonal sampling followed by quarterly and monthly for seagrass density and water quality data sampling.


163

4. Minimum Detectable Change (MDC%) decreases with increase of number of years of monitoring.

5. Coefficient of Variation (CV %) is the highest at seasonal sampling followed by quarterly, daily, monthly, bi-weekly and weekly in that order for salinity data sampling.

6. Coefficient of Variation (CV %) is the highest at seasonal sampling followed by quarterly and monthly for seagrass density and water quality data sampling.

7. Coefficient of Variation (CV %) decreases with number of years of monitoring.

8. Power percentage of detecting change increase with the increase in actual percentage of detecting long-term mean.

9. Power percentage of detecting change increase with the increase in years of monitoring. Contact Information: Jing-Yea Yang, Ph.D., P.E., Stanley Consultants, 1601 Belvedere Road, West Palm Beach, FL 33406, Phone: (561) 712- 2257, Fax: (561) 689-3003, Email: [email protected]


164

Relative Importance of Solid-Phase Phosphorus and Iron on Sediment-Water Exchange of Phosphate in Florida Bay Jia-Zhong Zhang1 and Xiao-Lan Huang1,2

1Ocean Chemistry Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL

2CIMAS, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL

Phosphate exchange across the sediment-water interface is largely controlled by the chemical composition and physical properties of sediments. Among the different metal oxide particles, amorphous iron oxides have been shown to have the greatest adsorption capacity for phosphate. Because iron is ubiquitous in the aquatic environment, the content of amorphous iron oxides in the sediments has been considered to be the most important factor in regulating sediment’s adsorption capacity. Coastal sediments are often coated with terrigenous amorphous iron oxides and those containing high iron are thought to have a high adsorption capacity. However, this conventional wisdom is based largely upon studies of phosphate adsorption on laboratory-synthesized minerals themselves containing no phosphorus. Natural particles, such as sediments, soils and dust, always contain phosphorus and abundance of which depends upon their origin and sedimentary environments. A total of 40 sampling sites across Florida Bay (USA) provided detailed spatial distributions both of the sediment’s zero equilibrium phosphate concentration (EPC0) and of the distribution coefficient (Kd) that are consistent with the distribution of the exchangeable phosphate content of the sediment samples that were previously determined using a sequential extraction method (Zhang et al., 2004). This study provides the first quantitative relationship between the exchangeable phosphate content of natural sediments (Pexch) and equilibrium phosphate concentration (EPC0):

EPC0 = 4.4494 Pexch + 57.31 (Pexch)2

And the relationship between the exchangeable phosphate content of natural sediments (Pexch) and distribution coefficient of phosphate in sediment-water system (Kd):

Kd = 0.0391 (Pexch)-0.886 Using natural sediments from Florida Bay that contain variable phosphorus and iron, our study clearly demonstrates that the exchangeable phosphate rather than the iron oxides of sediments governs the overall phosphate sorption behavior of sediments. Both EPC0 and Kd are primary regulated by Pexch. On the other hand, iron oxide content of sediment has no influence on EPC0 and it plays only a secondly role in regulating Kd, becoming important only in sediments poor in Pexch.

The regulating role of Pexch demonstrated in this study may be extended to other particle-reactive, environmentally important species, such as arsenic, heavy metals and some organic pollutants. Future studies on other particle-reactive species in sediments are essential to determine if the degree of adsorbate saturation on adsorbent surface, in general, regulates the adsorbent’s buffering intensity to changing absorbate concentration in aquatic systems.


165

References: Zhang, Jia-Zhong, Charles J. Fischer, and Peter B. Ortner, (2004) Potential availability of sedimentary phosphorus

to sediment resuspension in Florida Bay, Global Biogeochemical Cycles. 18(1):GB1038, doi: 10.1029/2004GB002255, 2004.

Zhang, Jia-Zhong and Xiao-Lan Huang (2007) Relative importance of solid –phase phosphorus and iron in sorption behavior of sediments. Environmental Science and Technology, 41(8): 2789-2795, DOI: 10.1021/es061836q.

Contact Information: Jia-Zhong Zhang, Ocean Chemistry Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, 4301 Rickenbacker Causeway,Miami, FL 33149 USA, Phone: 305-361 4512, Fax: 305-361-4447, Email: [email protected]


166

Quantity, Timing, and Distribution of Freshwater Flows into Northeastern Florida Bay, 1996-2007 Mark Zucker, Stephen Huddleston and Jeff Woods

U.S. Geological Survey, Florida Integrated Science Center, Ft. Lauderdale, FL, USA A central premise of the Comprehensive Everglades Restoration Plan (CERP) is to restore the quantity, timing and distribution of flow to the Greater Everglades and Florida Bay. The scientific consensus is that the quantity of freshwater flow delivered to Florida Bay has been reduced substantially; therefore, efforts to increase the quantity of flow to the Florida Bay are ongoing. Freshwater flows into northeastern Florida Bay have been measured between 1996 and 2007 at instrumented and non-instrumented estuarine creeks. The quantity of freshwater flow to northeastern Florida Bay is highly variable and ranged from 154,130 (2004) to 506,170 (2005) acre-feet. The improper timing of flow to the bay can result in a rapid decrease in nearshore salinities, negatively affecting fish and submerged aquatic vegetation. Lastly, the distribution of flow to northeastern Florida Bay suggests that more flow reaches the eastern portion of Florida Bay at the expense of Taylor Slough and central Florida Bay. Defining the pre-CERP baseline conditions for the quantity of flow to northeastern Florida Bay is ongoing. Climatic factors, as well as water management operations, contribute to the amount of freshwater delivered to the bay. The median flow for all sites from 1996 to 2007 equaled 317,120 acre-feet. Since 2000, three consecutive years of above average flow (2001-03) and two consecutive years of below average flow (2006-07) were observed, the latter as a result of severe drought conditions. The late August and October, 2005, landfall of two Hurricanes, Katrina and Wilma, resulted in a maximum measured annual flow volume. The timing of flow can be characterized by distinct wet- and dry-season patterns. The transition from the dry season to the wet season, as well as tropical storms and hurricanes, are important drivers that influence the timing of freshwater deliveries. Trout Creek is the main contributor of freshwater flow to northeastern Florida Bay, and is used herein to describe the importance of timing. The median flow at Trout Creek for June to July equaled 27,829 acre-feet, or about 20% of the total annual flow. The maximum flow delivered during the early wet season occurred in 1997, equaling 82,370 acre-feet. Freshwater flow into the bay was minimal during 1998, 2000, 2001, and 2004; the transition from the dry season to the wet season occurred after July in each case. A delay in freshwater deliveries can have detrimental effects, such as prolonging hypersaline conditions into the wet season. The percentage of discharge observed in the wet season is influenced by the El Niño/La Niña Oscillation, droughts, and tropical storms. An analysis of discharge timing for 1996-99 indicated 47.1% (1998) to 93.0% (1997, 1999) of the annual freshwater flow occurred during the wet season. In contrast, discharge timing for 2000-07 indicated 47.8% (2004) to 93.7% (2005) of the annual freshwater flow occurred during the wet season. The effects of tropical systems were evaluated by examining total flows for the months of September and October. The median flow volume for the months of September and October at Trout Creek equaled 60,630 acre-feet, or 50% of the total annual flow. In contrast, the minimum and maximum flow volume for the months of September and October equaled 31,300 (2004) and 137,560 (2005) acre-feet, respectively. As noted earlier, freshwater flow into Florida Bay was lowest in 2004, coinciding with a delay in the transition from the dry to the wet season.


167

The distribution of flow to northeastern Florida Bay was examined by comparing flow percentages for 1996-99 against 2000-07 for the following stations: West Highway Creek, Trout Creek, Taylor River Mouth, and McCormick Creek (fig. 1). The average percentage of annual flow during 1996-99 equaled 12.2%, 50.0%, 8.5%, and 2.5%, respectively. The average percentage of annual flow at these sites for 2000-07 equaled 11.1%, 44.0%, 10.1%, and 7.0%, respectively. The percentage of flow at West Highway Creek and Trout Creek decreased slightly over the period of record, and the percentage of flow at Taylor River Mouth and McCormick Creek increased slightly. The percentage shift in flow westward is about 8%. Sources of error include flow volumes estimated at several non-instrumented creeks using regression analysis and errors associated with use of index velocity methods in coastal areas.

Figure 1. Percentages of total annual flow at selected northeastern Florida Bay sites during 1996-99 and 2000-07. Contact Information: Mark Zucker, U.S. Geological Survey, Florida Integrated Science Center, 3110 SW 9th Ave, Ft. Lauderdale, FL 33315, USA, Phone: 954-377-5952, Fax: 954-377-5901, Email: [email protected]


168


169

Author Index Bold numbers indicate presenting authors.

Acevedo, Santiago ..................................................47 Adornato, Lori ....................................................... 133 Alexander, Jeffrey ............................................. 88, 96 Alleman, Richard............................................. 43, 143 Alvear, Elsa ........................................................... 150 Ana, Hoare...............................................................96 Armitage, Anna R............................................ 79, 157 Atkinson, Andrea................................................... 150 Avila , Christian L. ...................................... 45, 47, 53 Behringer, Jr., Donald C...................................... 5, 61 Bellmund, Sarah .............................................. 49, 103 Bergh, Chris.............................................................50 Bernard, Rebecca J. .................................................51 Berns, D...................................................................91 Blair, Stephen ................................ 29, 47, 49, 53, 103 Boudreau, Carrie .....................................................55 Boudreau, Jackie .....................................................72 Boyer, Joseph N. ................... 29, 56, 57, 64, 102, 111 Brandt, L. A........................................................... 149 Briceño, Henry O. ............................................. 57, 64 Browder, Joan A.................. 15, 59, 66, 105, 109, 147 Buck, Eric.............................................................. 105 Butler IV, Mark J................................................. 5, 61 Byrne, Robert ........................................................ 133 Camilli, Richard .................................................... 133 Campbell, Justin E...................................................63 Cannizzaro, J. ..........................................................98 Cardenas, Hernando ................................................59 Castañeda-Moya, Edward........................................25 Chambers, Randolph ..............................................25 Chartier, K. L......................................................... 149 Chen , M. ............................................................... 102 Cherkiss, M. S. ...................................................... 149 Childers, Daniel L. ..................................................25 Chimba, Deo.......................................................... 162 Clarke, Ernie.......................................................... 143 Collado-Vides , Ligia ..............................................77 Contillo, Joseph ..................................................... 123 Coronado-Molina, Carlos ........................................25 Cosby, B. J...............................................................64

Criales, Maria M................................................ 59, 66 Cristman, M.............................................................91 Crowder, Andrew G. ...............................................68 Cunniff, Kevin M. ................................................. 114 Dagg, Michael J..................................................... 112 Danielś, Andre....................................................... 147 Davis III, Stephen E. ...............................................25 Dean, Amanda .........................................................56 Decker, Jeremy...................................................... 153 Dorazio, Robert M................................................. 147 Durako, Michael J. ..............................................5, 91 Duryea, Anthony ................................................... 133 Engleby, Laura ...................................................... 123 Estep, Andy ........................................................... 150 Evans, David W.......................................................70 Fajans, Jonathan S. ..................................................68 Filina, Josh ..............................................................72 Flaherty, K. E. .........................................................73 Fletcher, Pamela ......................................................75 Fourqurean, James W. ......... 51, 63, 77, 79, 81, 83, 94 ................................................................... 97, 157 Frankovich, Thomas A. ..................................... 79, 83 Frezza, Peter ...................................................... 45, 85 Gaiser, Evelyn ............................................... 131, 156 Garis, Greg ...................................................... 49, 103 Garrison, Lance ..................................................... 123 Gerard, Trika L........................................ 86, 139, 159 Geselbracht, Laura...................................................87 Gibson, Patrick ...................................................... 133 Glibert, Patricia M. ...................................... 29, 88, 96 Gramer, Lew...................................................... 75, 98 Grant, Cidya S. ...................................................... 127 Graves, Greg............................................................49 Greene, Michael .................................................... 109 Hall, Brooke ...........................................................90 Hall, M. O............................................................ 5, 91 Hallac, David E. ......................................................93 Halun, Zayda ...........................................................94 Hamrick, John M. ....................................................95 Heil, Cynthia A............................................ 29, 88, 96


170

Hench , James ........................................................133 Hendee, James ...................................................75, 98 Herbert, Darrell A....................................................97 Herling, Fred............................................................93 Hitchcock, Gary L. ................................................112 Hogan , Peter J. ......................................................119 Hu, Chuanmin............................................75, 98, 119 Huang, Xiao-Lan ...................................................164 Huddleston, Stephen ..............................................166 Hudley, Joel W. .....................................................160 Hunt, Melody J. .....................................................101 Ikenaga, Makoto ......................................................56 Jackson, Thomas L. .........................................59, 105 Jaffé, Rudolf ..............................................25, 29, 102 Jensen, Henning S..................................................118 Ji, Zhen-Gang ..........................................................95 Jobert, Herve....................................................49, 103 Johns, Elizabeth M...........................98, 104, 121, 137 Johnson, Darlene R................................................105 Jolicoeur, Jean l. ....................................................145 Jones, David L. .....................................................107 Kang, HeeSook......................................................119 Kelble, Christopher R. ............98, 104, 109, 111, 112, .................................................................121, 137 Kelly, Stephen P. ...........................................114, 125 Kempinski, Sheri .....................................................47 Kiker, Gregory.........................................................75 Koch, Marguerite S....................29, 72, 116, 118, 135 Kourafalou, Vassiliki H. ................................104, 119 Krupa, Steve ............................................................49 Kucklick, John .......................................................123 Kunzelman, J. ..........................................................91 Lacroix, Mike ........................................................109 Lamkin, John ...................................................86, 159 Lee, Thomas N.......................................104, 121, 137 Li, Yuncong .............................................................75 Liehr, Gladys .........................................................105 Lindquist, Niels......................................................133 Litz, Jenny .............................................................123 Liu, Xuewu ............................................................133 Lohmann, Melinda.................................................153 Lorenz, Jerome J..............................................85, 149 Louda, J. William ..........................................125, 127

Madden, Christopher J..................29, 72, 88, 96, 114, .........................................................118, 129, 135 Maie, N. .................................................................102 Malca, E...........................................................86, 159 Markley, Susan ........................................................53 Marlowe, Beth .........................................................90 Marshall, Frank E. ...........................................64, 131 Martens, Christopher S. .........................................133 Matheson, Jr., R. E...................................................73 Mazzotti, F. J. ........................................................149 McDonald, Amanda A...................................129, 135 McMichael, Jr., R. H. ..............................................73 Melo, Nelson ...................................98, 104, 121, 137 Mendlovitz, Howard ..............................................133 Merello, M. ..............................................................91 Meselhe, Ehab..........................................................25 Michot, Beatrice ......................................................25 Mitchell, Carol L. ..................................................111 Mongkhonsri, Panne ......................................125, 127 Morgan, Anne B. ...................................................139 Morrison, Douglas ..................................................83 Muller-Karger, F......................................................98 Murasko, Sue .....................................................88, 96 Murray , James B...................................................140 Neely, Merrie Beth ....................................88, 96, 142 Nielsen, Ole ...........................................................118 Noe, Gregory B........................................................25 Nuttle, W. ................................................................64 Ortner, Peter B. ................34, 104, 111, 112, 121, 137 Paris, Claire ...........................................................119 Parish, K. ...............................................................102 Patterson, Judd.......................................................150 Patterson, Matt.......................................................150 Pearlstine, Leonard ..................................................93 Phillips, Emily .......................................................140 Pierre , Maurice .......................................................53 Pisani, Cristina.........................................................56 Pitts, Patrick...................................................131, 143 Popp, Brian ............................................................133 Porch, Clay E. ........................................................109 Powell, Allyn B. ....................................................109 Price, René M. .................................29, 102, 145, 151 Reich, Chris ...........................................................155 Renshaw, Amy.......................................................103


171

Rivera-Monroy, Victor H. .......................................25 Robblee, Michael B. .......................... 59, 66, 105, 147 Romanach, S. S. ....................................................149 Rudnick, David T. ....... 25, 29, 53, 114, 118, 145, 155 Rumbold, Darren .....................................................70 Ruttenberg, Benjamin I. ........................................150 Sadle, Jimi ...............................................................93 Schill, William B. .................................................. 140 Schopmeyer, Stephanie ...........................................72 Scinto, L. ............................................................... 102 Serafy, Joseph E. ........................................... 105, 107 Shafer, Mark.......................................................... 143 Shaw, Douglas ........................................................87 Shaw, Forrest...........................................................53 Sidner, Jonathan ......................................................47 Sklar, Fred ...............................................................25 Smedstad, Ole Martin............................................ 119 Smith, Ned............................................................. 121 Smith, Ryan H. ...................................... 104, 121, 137 St. Clair, Tom .........................................................90 Stalker, Jeremy C. ......................................... 145, 151 Swain, Eric ............................................................153 Swart, Peter K........................................................ 151 Swarzenski, Peter W..............................................155

Teare, Brian ........................................................... 105 Toth, K. ...................................................................91 Troxler, Tiffany .......................................................25 Twilley, Robert R. ...................................................25 Vargo, Gabriel A. .................................................. 142 Waara, Robert........................................................ 150 Wachnicka, Ania ........................................... 131, 156 Walter, John F. ...................................................... 107 Weaver, C. A. ........................................................157 Whitcraft, S. .........................................................159 Wilcox, Sue .............................................................90 Wilson , Kathryne....................................................53 Wingard, G. Lynn.............................. 9, 131, 140, 160 Witcher, Brian ....................................................... 150 Wittman, Kevin ..................................................... 143 Woods, Jeff...................................................... 55, 166 Wright, A.................................................................86 Yamashita, Y. ........................................................ 102 Yang, Jing-Yea......................................................162 Zapata-Rios, Xavier............................................... 145 Zhang, Jia-Zhong........................................... 118, 164 Zucker, Mark ................................................... 55, 166


172

Notes


173

Notes


174

Notes

2008 florida bay and adjacent marine systems science conference

Documents