Water Resources Research Act Program

Principal Investigators: Christopher Guy, Brian Bellgraph

Abstract: Sauger Sander canadensis are an important sportfish in Montana and were historically abundant throughout the Missouri and Yellowstone river drainages (McMahon and Gardner 2001). However, sauger populations throughout Montana have recently experienced declines in abundance as well as a decrease in their historical range (McMahon and Gardner 2001). Walleye Sander vitreus are a close relative of sauger and have been introduced to many water bodies throughout Montana, but are not native to the state. Due to their close relationship and ecological similarities, non-native walleye may be outcompeting sauger for food and habitat resources. Since sauger are native top-predators in large river ecosystems of Montana, their decline in abundance could have deleterious effects on large-river ecosystem structure and function. Thus, my research will compare the movements, habitat use, and food habits of sauger and walleye in order to assess any potential competition and propose management actions that preserve native sauger in the Missouri River.