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Mark P Gaikowski

Midcontinent Deputy Regional Director for Science

Office of the Midcontinent Regional Director

Office Phone: 608-738-3834
ORCID: 0000-0002-6507-9341

La Crosse , WI

Supervisor: Jennifer A Lacey
Description of Work This spring (2014) we will measure Asian carp eDNA over time at a Missouri River site downstream of multiple spawning areas before and during spawning. We will measure the amount of Asian carp eDNA in water samples. The amount of eDNA will be related to the numbers of eggs and larvae counted in matched samples (water samples taken at the same time and place). The time since the eDNA was released by the carp will be estimated and these results will be related to the average age of AC eggs and larvae in matched samples. We will also test for substances which interfere with the eDNA measurement techniques and can lead to false negatives. We will also be validating markers developed by USGS and...
Description of Work In separate studies, bighead carp and silver carp were raised in waters of varying hardness. Survival, correct development, and hatching success were monitored. Additionally, a search of the Asian literature (including Chinese-language literature) on water hardness in areas where Asian carp are native was performed. Relevance & Impact If soft water limits Asian carp hatching success, then this would mean that large areas of the Great Lakes and east and west coast drainages would not be at risk of Asian carp establishment. Key Findings Both bighead carp and silver carp developed normally and the eggs hatched normally in all water hardnesses tested, including very soft water. The Yangtze River,...
There is an immediate need for effective and safe tools to prevent the spread of planktonic larval dreissenids (quagga Dreissena rostriformis bugensis and zebra mussels D. polymorpha) and to rehabilitate and protect native unionid habitats by controlling existing dreissenid mussel populations in and around the Great Lakes. More than half of the 78 native unionid species in Minnesota, Wisconsin, Iowa, Missouri, Illinois, Indiana, and Ohio are listed as endangered, threatened, or of special concern. Although the US Fish and Wildlife Service (USFWS) considers zebra mussels to be an immediate threat to freshwater unionids in the Upper Mississippi River System, there is no effective tool to control established zebra...
Locks and dams are possible management points to block the spread of invasive Asian carps in the United States. Infusion of carbon dioxide (CO2) into water is one deterrent strategy being considered at navigational structures to reduce upstream fish passage that would not directly interfere with lock and dam operations. The goal of this study was to determine the efficacy of CO2 as a behavioral deterrent to free-swimming fishes. Telemetered bighead carp (Hypophthalmichthys nobilis) and grass carp (Ctenopharyngodon idella) were monitored within a U-shaped pond (30.5 m long x 13.7 m wide x 1 m deep) using a two-dimensional acoustic telemetry array. Gaseous CO2 was administered to one-half of the pond at 30, 75, or...
Description of Work This work began by assembling fish toxicant data into a common database and examining the database for trends in toxicant data. The trends found in the toxicant database were linked to physiochemical properties of the individual toxicants. Combining the toxicant trends with the physiochemical properties may allow for the prediction of toxicity and the identification of chemicals with selectivity for the Asian carp. Identifying a selective toxicant may provide control of Asian carps while minimizing effects on other non-target aquatic species. When Asian carp specific toxicants are identified from the initial screen within the database these toxicants are then further screened in toxicity assays...
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