Just Go with the Flow: Documenting Sturgeon Use of the Lower Missouri River Floodplain

Heavy snowpack accumulation and rainfall in the upper Missouri River Basin resulted in unprecedented releases from the Missouri River mainstem reservoirs in 2011.  Record releases from Gavins Point Dam in South Dakota brought widespread inundation of the floodplain for more than 400 miles downstream to Kansas City, Missouri. Nebraska Game and Parks Commission researchers studied three inundated habitat mitigation sites (Boyer Chute National Wildlife Refuge, Schilling State Wildlife Management Area, and the William Gilmour State Wildlife Management Area) along the Missouri River to determine if newly available floodplain habitat was being utilized by Sturgeon.  Acoustic telemetry was used to search the sites for the presence of previously tagged pallid sturgeon Scaphirhynchus albus. These tags were implanted into adult pallid sturgeon as part of a long-term study of movement and habitat use in the Lower Missouri River. To bolster the telemetry data as well as determine floodplain use by untagged pallid sturgeon and shovelnose sturgeon Scaphirhynchus platorynchus, 24 randomly placed trotlines were deployed at each site.  Trotlines were deployed for 3 hours and contained 40 hooks baited with nightcrawlers.  Five implanted pallid sturgeon were relocated by telemetry at 2 of the 3 sites. No pallid sturgeon were captured from the randomly selected trotline locations; however, 47 shovelnose sturgeon were collected from 72 short-duration trotlines. Additionally, an acoustic Doppler current profiler was used to collect depth and velocity data for floodplain habitats being utilized by implanted pallid sturgeon.  Results suggest that both species of sturgeon will use portions of reconnected inundated habitats.