Cooperative Fish and Wildlife Research Units Program: Wisconsin Fishery
Education, Research and Technical Assistance for Managing Our Natural Resources

Lake sturgeon Acipenser fulvescens populations in the Great Lakes have undergone dramatic declines over the last two centuries for a variety of reasons, including dam construction. These declines have led to closures of commercial, recreational, and tribal subsistence fisheries and the listing of lake sturgeon as threatened, endangered, or a species of special concern in many states in the Great Lakes region. Historically, lake sturgeon probably spawned in many tributaries to the Great Lakes, but hydroelectric dams now prevent fish from reaching historic spawning areas. During a lake sturgeon workshop sponsored by the Great Lakes Fishery Trust (GLFT) in 2000 (Holey et al. 2000), participants identified these barriers as one of the greatest impediments to lake sturgeon recovery in the Great Lakes, including Lake Michigan. In 2011, the GLFT held another workshop to further define research needs associated with passing lake sturgeon at hydroelectric facilities (Coscarelli et al. 2011) and passage of sturgeon has become an increasingly important priority for natural resource agencies. Furthermore, Jager (2006) suggested that reconnecting sturgeon populations through passage should benefit populations because: 1) populations in connected river segments are more likely to recolonize neighboring segments after extirpation, especially in small river segments and 2) passage should increase habitat availability for all life history stages because of habitat diversity among river segments. Consequently, developing effective means to pass lake sturgeon through or around barriers has become an important priority for natural resource agencies around the Great Lakes. While many questions regarding the design and effectiveness of passage devices still exist, it will also be essential to determine how lake sturgeon behave following passage through or around hydroelectric facilities. Specifically, it will be important to determine if and when lake sturgeon passed upstream participate in spawning and whether differences in timing of passage and the biological attributes of fish (i.e., length, sex, and maturity) affect lake sturgeon behavior after passage. Currently, hydroelectric dams prevent lake sturgeon entering the lower Menominee River from Green Bay from reaching high-quality spawning locations and juvenile fish habitat available upstream. Fish passage through the lower two dams on the Menominee River is targeted to begin in 2014 and fishery managers with the Wisconsin and Michigan Departments of Natural Resources (DNR) will need to determine the numbers and characteristics of lake sturgeon that should be allowed to pass in order to maximize recruitment potential. To answer these questions, fishery managers need information regarding when and if fish passed upstream participate in spawning and whether or not these fish return downstream using a fishway specifically constructed for this purpose. Our proposed research will use acoustic telemetry to describe movement of lake sturgeon passed upstream in the Menominee River and will provide fishery managers around the Great Lakes with information that can be used to formulate passage strategies and possibly help design passage facilities for lake sturgeon.