Freshwater Mussel Recovery for Water Quality and Habitat Improvement in Southeastern Pennsylvania

Danielle KreegerPartnership for the DE Estuary

Rebuilding Bivalve Biodiversity, Populations and Ecosystem Services as a Basis for Ecosystem Restoration

Danielle KreegerPartnership for the DE Estuary

Healthy Bivalves = Healthy Watersheds

Bivalves of the Delaware

DRBC

Crassostrea virginica

Elliptio complanata

Geukensia demissa

11 Other Species of Freshwater Unionid Mussels

Mya arenaria

Rangia cuneata

Corbicula fluminea

Mytilus edulis

Ensis directus

Mercenaria mercenaria

BivalvesOyster Trends

http://www.epodunk.com/cgi-bin/genInfo.php?locIndex=25475

Oyster landings in Delaware Bay: 1880 - 1980s

Oyster Reef Revitalization

Bivalves

Ortmann, A.E. 1919. A monograph of the naiades of Pennsylvania. Part III: Systematic account of the genera and species. Memoirs of the Carnegie Museum 8(1):

Freshwater Mussel Status and Trends

Loss in Biodiversity

Scientific Name Scientific Name DE NJ PAALASMIDONTA HETERODON DWARF WEDGEMUSSEL Endangered Endangered Critically Imperiled

ALASMIDONTA UNDULATA TRIANGLE FLOATER Extirpated ? Threatened Vulnerable

ALASMIDONTA VARICOSA BROOK FLOATER Endangered Endangered Imperiled

ANODONTA IMPLICATA ALEWIFE FLOATER Extremely Rare no data Extirpated ?

ELLIPTIO COMPLANATA EASTERN ELLIPTIO common common Secure

LAMPSILIS CARIOSA YELLOW LAMPMUSSEL Endangered Threatened Vulnerable

LAMPSILIS RADIATA EASTERN LAMPMUSSEL Endangered Threatened Imperiled

LASMIGONA SUBVIRIDIS GREEN FLOATER no data Endangered Imperiled

LEPTODEA OCHRACEA TIDEWATER MUCKET Endangered Threatened Extirpated ?

LIGUMIA NASUTA EASTERN PONDMUSSEL Endangered Threatened Critically Imperiled

MARGARITIFERA MARGARITIFERA EASTERN PEARLSHELL no data no data Imperiled

PYGANODON CATARACTA EASTERN FLOATER no data no data Vulnerable

STROPHITUS UNDULATUS SQUAWFOOT Extremely Rare Species of Concern Apparently Secure

State Conservation Status

Patchy, Impaired

Extirpated

Rare

NEP Study NEP Study AreaArea

•

Culprits

Habitat Loss and Degradation

WaterQuality

Exotic Species

Photo by D. Kreeger

Freshwater Mussel Larvae Require Fish Hosts

Freshwater Mussel Larvae Require Fish Hosts

Fig

ure

fro

m C

um

min

gs

an

d M

ayer

(19

92

).

Most mussels

depend on particular

fish species

Larvae are brooded in the ctenidia

Documenting the Decline

PopulationBiomass

Biodiversity

CTUIR Freshwater Mussel Project

Nature’s BenefitsNature’s BenefitsBivalve Shellfish are Bivalve Shellfish are “Ecosystem Engineers“Ecosystem Engineers”

DK 15

Loss of Ecological Services1. Structure

Binding of Bottom

Bottom Turbulence

Habitat Complexity

2. Function

Suspended Particulates

Particulate N, P

Light

Sediment Enrichment

Dissolved Nutrients

StartStart

8 adult mussels8 adult musselsNo musselsNo mussels

Biofiltration PotentialBiofiltration Potential

Slide from Dick Neves, VA Tech

LaterLater8 adult mussels8 adult musselsNo musselsNo mussels

Slide from Dick Neves, VA Tech

Biofiltration PotentialBiofiltration Potential

Brandywine RiverStudied 2000 - present

Map from The Brandywine River Conservancy

Elliptio complanata

Elliptio complanata

Photos by Kreeger

To Understand EcoServices, Need…

Physiology

PopulationSurveys

Ecology

Monitoring, Variability

Physiology Measurements

e.g., Clearance Rate

In Lab In Field

Population Measurements

Abundance (# m-2, # mile-1)Total Area (m2, river miles)

Size Class Structure

Body Size

Map from The Brandywine River Conservancy

One Mussel Bed in a 6 mile reach of the Brandywine River

Estimated Removal = 7.1 %

Filters >25 metric tons dry suspended solids per year

Data from Kreeger, 2006

Water Processing Estimate

Elliptio complanata

4.3 Billion Elliptio Filter 9.8 Billion Liters per Hour

Bivalves

0.30

0.50

0.70

0.90

1.10

1.30

1.50

Particle Sizes

Do

wn

stre

am R

elat

ive

to

Up

stre

am C

on

cen

trat

ion

May

June

2-3 µm3-4 µm

10-15 µm

4-6 µm

6-10 µm

15-63 µm

Size Selection: particle sizes below a mussel bed

Pennate Diatoms

Phytoplankton

Heterotrophic Protists

Detritus Complex

Centric Diatoms

Bacteria

Natural Diets and Particle Type Selection

Pennate Diatoms

Phytoplankton

Heterotrophic Protists

Detritus Complex

Centric Diatoms

Bacteria

Water Quality & Grazing Impacts of Populations

Susquehanna

Delaware Bay Oysters

Crassostrea virginica

Brandywine River, PA

Geukensia demissa

Delaware Estuary Marshes

Elliptio complanata

Brandywine River, PABrandywine River, PA

Population-Level Water ProcessingB

illi

on

s o

f L

iter

s p

er H

ou

r

0

10

20

30

40

50

60

Elliptio complanata

Geukensia demissa

Crassostrea virginica

Restoration of Nature’s Benefits?

BivalvesNature’s Benefits

(aka Natural Capital)

Six Reasons Why We Care

1. BiodiversitySpecies Loss: ↓ Intrinsic Losses

↓ Niches Filled ↓ Human Health

2. Biomass (Populations)

Biomass Loss: ↓ EcoServices

↓ Fish & Wildlife ↓ Human Health

CTUIR Freshwater Mussel Project

3. Bioindicator ValueInternational Mussel Watch

Freshwater Caging Studies

Contaminant and Site-Specific Testing, Monitoring

Tributary and Regional Bioassessment

Deployed Cages

4. Commercial ValueShellfisheriesJewelryPearl Shell Industry

5. Cultural-Historical Native American UsesWaterman LifestyleEcotourism

6. Human HealthPathogen Removal

- filter and digest harmful bacteria and protists

Model Organisms

- for medical sciences (e.g. cancer research)

TMDL applications- can reassembled bivalve communities

help managers address TMDL’s?

Nature’s Benefits (Natural Capital)

Lives

Livelihoods

Health

Livelihoods

Health

DRBC

Desired Watershed Condition:A diverse and robust assemblage of native bivalves living in abundance in all available tidal and non-tidal ecological niches and providing maximum possible natural benefits.

System Linkages ?

DRBC

Crassostrea virginica

Elliptio complanata

Geukensia demissa

11 Other Species of Freshwater Unionid Mussels

Mya arenaria

Rangia cuneata

Corbicula fluminea

Mytilus edulis

Ensis directus

Mercenaria mercenaria

Freshwater Mussel Recovery Program

Elliptio complanata

• Phase 1Prioritize Streamsfor Restoration

• Phase 1Reciprocal Transplantsand Condition Monitoring

Tagging Mussels

Phase 1Reciprocal Transplants and

Condition Monitoring

Cage Deployment

Phase 1Reciprocal Transplants and

Condition Monitoring

Deployed Cages

Matt Gray thesis research (Drexel)

Matt Gray thesis research (Drexel)

Important for Overwintering

Matt Gray thesis research (Drexel)

Important for Reproduction

Phase 2Propagation and Reintroduction

Cheyney Hatchery

Fish Infestation

Fish from Academy of

Natural Sciences

Larval Transformation Into Juveniles

Phase 2Propagation and Reintroduction

Photos, R. Neves, VA Tech

Propagated Juveniles

Freshwater Mussel Recovery Program

0200400600800

1,0001,2001,4001,6001,8002,000

Millions of Liters

Processed

1 2 4 6 8 10 15 30

Years After Planting

Not including progeny

Goals Based on Ecosystem Services

• Range Shifts with No Dispersal• Habitat Degradation (T, salinity, pH, fish hosts)

Bivalve Vulnerability?

Freshwater Mussel Beds

• Loss and Degradation of Wetland Habitat• Others: Food, PH

Salt marsh Mussel Beds

• Salinity Driven Disease Epizootics• Others: Food, pH

Oyster Reefs

Scientific Name Scientific Name DE NJ PAALASMIDONTA HETERODON DWARF WEDGEMUSSEL Endangered Endangered Critically Imperiled

ALASMIDONTA UNDULATA TRIANGLE FLOATER Extirpated ? Threatened Vulnerable

ALASMIDONTA VARICOSA BROOK FLOATER Endangered Endangered Imperiled

ANODONTA IMPLICATA ALEWIFE FLOATER Extremely Rare no data Extirpated ?

ELLIPTIO COMPLANATA EASTERN ELLIPTIO common common Secure

LAMPSILIS CARIOSA YELLOW LAMPMUSSEL Endangered Threatened Vulnerable

LAMPSILIS RADIATA EASTERN LAMPMUSSEL Endangered Threatened Imperiled

LASMIGONA SUBVIRIDIS GREEN FLOATER no data Endangered Imperiled

LEPTODEA OCHRACEA TIDEWATER MUCKET Endangered Threatened Extirpated ?

LIGUMIA NASUTA EASTERN PONDMUSSEL Endangered Threatened Critically Imperiled

MARGARITIFERA MARGARITIFERA EASTERN PEARLSHELL no data no data Imperiled

PYGANODON CATARACTA EASTERN FLOATER no data no data Vulnerable

STROPHITUS UNDULATUS SQUAWFOOT Extremely Rare Species of Concern Apparently Secure

State Conservation Status

Shifts in Species Ranges of Shifts in Species Ranges of Freshwater MusselsFreshwater Mussels

Patchy, Impaired

Elliptio complanata

Rare

Strophitus undulatus

Extirpated

Alasmidonta heterodon

Tough Decisions Which species and associated benefits can be

sustained?Which should we invest in? (since funding will

always be limited)

Summary

• Like marine species, freshwater mussels provide multiple benefits to people

DRBC

• Freshwater mussels are great targets for “ecosystem-based management.” If they are present, diverse and abundant, then the system is healthy

• Restoring mussel species and populations can improve water quality and ecological health downstream

• Freshwater mussels are the most imperiled plants and animals, including in our watershed

- End -

www.DelawareEstuary.org