Aggregative predation responses from Walleye on White Sturgeon in Lake Roosevelt, WA
Faculty Mentor
Paul Spruell
Document Type
Poster
Start Date
10-5-2023 11:15 AM
End Date
10-5-2023 1:00 PM
Location
PUB NCR
Department
Biology
Abstract
Seasonal prey abundance can drive predatory fishes to aggregate in areas of high prey density. This project aims to determine whether Walleye (Sander vitreus) are exhibiting an aggregative predation response to larval White Sturgeon (Acipenser transmontanus) drifts in the Lake Roosevelt system, which is a reservoir of the Columbia River in Washington State. Sturgeon are a long-lived ancient species of anadromous fish that spawn in the summer months and are native to the Columbia River basin. Populations of sturgeon are threatened worldwide and have recreational, economic, historical, and intrinsic values wherever they are found. Walleye are a popular nonnative piscivorous game fish that were illegally introduced to Lake Roosevelt in the 1950’s. Walleye in this study will be obtained through angling, electrofishing, and gillnetting. Samples will be taken during pre-spawn, peak spawn, and post-spawn time frames from May to October 2023. Stomachs from Walleye will be dissected and analyzed for presence of prey, using DNA barcoding to identify prey items to the species level. If a higher proportional presence of larval White Sturgeon is found within Walleye stomachs during the spawning season, it may indicate a shift in foraging behavior or prey selectivity as the Walleye aggregate to the upper Columbia arm of Lake Roosevelt where the larval drifts occur. Results from this research will be used to inform ongoing management decisions regarding populations of White Sturgeon in Lake Roosevelt.
Recommended Citation
Barr, Seth, "Aggregative predation responses from Walleye on White Sturgeon in Lake Roosevelt, WA" (2023). 2023 Symposium. 13.
https://dc.ewu.edu/srcw_2023/res_2023/p2_2023/13
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Aggregative predation responses from Walleye on White Sturgeon in Lake Roosevelt, WA
PUB NCR
Seasonal prey abundance can drive predatory fishes to aggregate in areas of high prey density. This project aims to determine whether Walleye (Sander vitreus) are exhibiting an aggregative predation response to larval White Sturgeon (Acipenser transmontanus) drifts in the Lake Roosevelt system, which is a reservoir of the Columbia River in Washington State. Sturgeon are a long-lived ancient species of anadromous fish that spawn in the summer months and are native to the Columbia River basin. Populations of sturgeon are threatened worldwide and have recreational, economic, historical, and intrinsic values wherever they are found. Walleye are a popular nonnative piscivorous game fish that were illegally introduced to Lake Roosevelt in the 1950’s. Walleye in this study will be obtained through angling, electrofishing, and gillnetting. Samples will be taken during pre-spawn, peak spawn, and post-spawn time frames from May to October 2023. Stomachs from Walleye will be dissected and analyzed for presence of prey, using DNA barcoding to identify prey items to the species level. If a higher proportional presence of larval White Sturgeon is found within Walleye stomachs during the spawning season, it may indicate a shift in foraging behavior or prey selectivity as the Walleye aggregate to the upper Columbia arm of Lake Roosevelt where the larval drifts occur. Results from this research will be used to inform ongoing management decisions regarding populations of White Sturgeon in Lake Roosevelt.
