nebraska zebra mussel case studies - … zebra mussel case studies allison zach, coordinator ....
TRANSCRIPT
Nebraska Zebra Mussel Case Studies
ALLISON ZACH, COORDINATOR
ZorinskyCarter
4 Positive Waterbodies2 Suspect Waterbodies
Offutt AFB Lake (Bellevue)113 acre lakeZM found in 2006Closed outlet tubes taking water to the MO riverBanned motorized boats from being usedTreated with copper sulfate in 2008 and 2009 New infestation found in 2014Research has been done annually since 2014 to monitor the populationIntroduction of 60,000 redear sunfish
July 30, 2014Found juveniles covering rocks
JUNE 6, 2014
September 26, 2014Found far less zebra mussels than in July and August. They had grown to adult size.
Offutt AFB lake zebra mussel densitiesCollection Date Average Density Water Temperature
5/29/2015 56 626/1/2015 192 63
6/26/2015 121 727/1/2015 22 77
7/17/2015 96 848/7/2015 2 86
1,500 µl/sub sample
Unmanned Aerial Vehicle Sampling
•Filters gallons of waters through a filter
•Successfully sampled veligers in 2015
•Revisions would be needed to increase detection using this method
•Easy to use at multiple waterbodies due to removal tube and filter
Future plansCover rip rap in the lake to reduce available habitat
Lake Zorinsky (Omaha)
• 2009 beer can found by boy scout
• USACE drew down 255 acre lake 17 feet in winter 2010
• Refilled in 2011 & reopened in 2012
Outlet
• Public report in May 2016-found one on a fishing line
• Took water samples the next day
• Veliger was identified by NISP on 5/25
• On 6/22 MT lab confirmed veligers (3 life stages observed)
• USACE and NGPC technicians surveyed for adult mussels
• eDNA confirmed week before July 4th
• Was then considered a suspect waterbody
3 separate plankton tows on 5/24
These 3 Life Stages Observed (>100/280 ml)
Confirmed veligers found from sample collected here
NGPC Technician searched for adult ZM in these areas 6/25
•Suspect waterbody signage was posted
•No plans to draw down the lake
•Will be considered suspect until an adult is confirmed
•Conducted boater surveys to determine travel patterns of lake users
AIS Watercraft Inspections & Outreachwill have 8 Techs this year
• Tablet Surveys
• Real time results
• Study travel patterns to target inspections and outreach areas
Watercraft Owner Behaviors90%
26%
45%
77%
39%
92%
21%
46%
95%
42%
82%
44%
95% 96%
Drained Water Flushed Motor Rinsed with Water Visually Inspected Removed Vegetation
2012 2013 2014
AIS Program funded by motorboat fee
◦Resident motorboat registration fee ($5) every 3 years◦Non-resident motorboat AIS sticker ($15) annually
NGPC AIS Program
Lewis & Clark Lake31,400 surface acres
90 miles of shore line
Max depth 45 feet
Lewis & Clark Lake
November 2014-Single Adult found on Midway boat ramp dock
August 18, 2015-Adult zebra mussels were found on 2 boats at a SD boat repair shop
August 19-SD did snorkeling in marinas
The mussels were of multiple sizes, indicating that zebra mussels are reproducing in Lewis and Clark Lake
Lewis & Clark Lake
What is Being done at Lewis & Clark LakeTransportation zone in SD
2 full time techs with decon units
Study with divers of ZM population
Certifying boat shops and marinas to decon watercrafts
Nebraska survey of slip renters
Nebraska technician
Municipal water and irrigators put in touch with other state contacts
MO River Zebra MusselsAdult zebra mussels found at MO River boat launches in 2016
The entire length of MO River in Nebraska is considered infested with zebra mussels
Watercrafts in the MO River NEED: to Clean, Drain & Dry for at least 5 days prior to relaunch
2016 Zebra Mussel Finds on MO River boat launches
Fort Calhoun
North Omaha
NE City
Omaha Public Power District FacilitiesFACILITY DATE NUMBERS OBSERVED
Fort Calhoun 3/14/2016 2
Fort Calhoun 4/20/2016 4
Fort Calhoun 9/6/2017 10,000
North Omaha 2/8/2017 20
NE City 5/18/2017 6
NE City 6/6/2017 500
NE City 8/23/2017 10,000
NE City 10/4/2017 6,200,000
Nebraska City Station
10/4/2017~ 6 million Observed
OPPD’s Pathway ForwardThe immediate action following the large numbers observed at NCS was to create a Work Request to power wash and remove the mussels on the intake screen mesh was created.
A project to perform an assessment of treatment options has been implemented. This project includes all three of our generation facilities along the Missouri River (NOS, NCS, FCS).
While waiting for a permanent solution to be implemented, manually cleaning is being used on selected equipment to insure plant operability without de-rates.
Learn More at: Neinvasives.com
