Early Detection Monitoring for Zebra and Quagga Mussels in Alaska Lakes

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1 Early Detection Monitoring for Zebra and Quagga Mussels in Alaska Lakes Upper Tangle Lakes Dan Bogan Alaska Natural Heritage Program aquatic.uaa.alaska.edu

2 History of Dreissena spp. in North America Accidentally introduced to the Great Lakes in the 1980s Spread rapidly to watersheds of the eastern US over the next two decades Found west of the Rockies for the first time in 2007 Spread to many lakes/reservoirs in Colorado, Utah, Arizona, Nevada, & California

3 History of Dreissena in North America

4 History of Dreissena in North America

5 History of Dreissena in North America

6 History of Dreissena in North America

7 History of Dreissena in North America

8 History of Dreissena in North America

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11 Ecological Consequenses Ecological impacts can vary from waterbody to waterbody, based on water chemistry and physical characteristics Since mussels are filter-feeders, they reduce plankton, disrupting the food web Increased water clarity allows aquatic plants to grow in deeper water Can cause increased occurrence of toxic algal blooms Can out compete native unionid mussels (Anodonta spp.)

12 Economic Consequences Can foul water delivery systems in potable water and energy generating facilities Eradication can cost more than $30K per acre Disruption of salmon rearing in some lakes could prove disastrous Once introduced, decontamination stations and intensive monitoring are expensive

13 Dreissena spp. life cycle Females produce 1 million eggs/year Zooplankton community in early life stages Attach to benthic community as adults Typically live 3-5 years in North America

14 Factors influencing introductions Public access, since main vectors are watercraft from infested lakes Public use especially boaters Proximity to known infestations Dissolved calcium requirements minimum of 8-9mg/L optimal >25mg/L ph limits (7.3 to 9.0, with optimal 7.5 to 8.7)

15 Monitoring and Prevention in Western states 100 th Meridian Initiative s Interagency Dreissena Monitoring Plan for Western Waters Education Boat inspections and boater surveys Involve commercial boat haulers Monitor Rapid response ID pathways and risk evaluation Evaluation

16 Prioritizing at-risk lakes in Alaska Public boat launches Proximity to Canadian border Known calcium concentrations Public use data Cumulative priority score Fielding Lake

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18 Evaluation of early detection methods Larval collection Cross Polarized Light Microscopy Image-Based Flow Cytometry PCR assays Monitoring for adults Visual surveys Artificial substrate sampling

19 Other data collected Secchi depth Calcium Physicochemical parameters ph Specific conductance Dissolved oxygen Temperature Boats/trailers

20 Some priority sites were not sampled Access issues warning signs unimproved boat launches poor public signage no calcium data (or difficult to find)

21 Results No Dreissena spp. were detected in any of the 25 lakes sampled. Calcium values were used to refine priority scores. Baseline data collected for priority sites Summit Lake

22 Alaska Natural Heritage Program Lakes Sampled Alaska Highway Denali Highway Deadman Lake Round Tangle Lake Richardson Highway Upper Tangle Lakes Chena Lake Quartz Lake Birch Lake Lost (Chisholm) Lake Harding Lake Summit Lake Paxson Lake Glenn Highway Fielding Lake Long Lake Clearwater Lake Lake Louise Beach Lake Kenai Lake Parks Highway Big Lake Finger Lake Nancy Lake Lucile Lake Loberg Lake Cottonwood Lake Sterling Highway Kenai Lake Hidden Lake Skilak Lake Seward Highway Upper Trail Lake

23 Next steps Inform other western states of our initial monitoring results; coordinate future efforts Develop a long term monitoring and outreach strategy Work with partners to gather better user data to more accurately identify priority sites Develop risk assessments and rapid response plans for high priority waterbodies Additional research on float planes as potential vectors Lake Louise

24 Thanks to Tammy Davis, ADF&G Dustin Merrigan, AKNHP Gary Lester, EcoAnalysts Cecil Rich, USFWS Matt Varner, BLM Alaska Birgit Hagedorn, UAA ASET Lab Jesse Schultz, Washington DFW Thomas Woolf, Idaho State Dep. of Ag Fielding Lake