Feasibility of an acoustic telemetry grid to determine adult white sucker spatial ecology

GBSUC

April 2022 - May 2027

Despite being abundant across the Laurentian Great Lakes (GLs), suckers (Catostomidae) are relatively understudied native fishes. Their ecological importance as prey for many other species has long been recognized, and their role in providing spawning grounds with nutrient subsidies that support river and nearshore food webs has been documented recently. Healthy and sustainable fisheries rely on resilient ecosystems where all native species thrive, and an improved understanding of the spatial ecology of non-game fishes in the GLs can strengthen management plans for recreationally and commercially important species. Previous work on the spatial ecology of non-game species such as white suckers (Catostomus commersonii) is scarce and has focused largely on degraded habitats. While these studies are valuable, it is important to have baseline data regarding animal behaviour outside of impaired areas. Insights into sucker spatial ecology outside of degraded habitats is often limited to assessments of movements during spawning migrations and does not capture habitat usage across multiple seasons. There is a pressing need to understand individual and collective movement year-round for the most abundant migratory fish in the GLs. Acoustic telemetry is a powerful tool for documenting fish movements within the GLs, particularly since the establishment of the Great Lakes Acoustic Telemetry Observation System (GLATOS) that enables sharing of resources and knowledge. In Lake Michigan, GLATOS researchers have begun deploying grid arrays to document the spatial ecology of lake trout (Salvelinus namaycush), lake whitefish (Coregonus clupeaformis), and cisco (Coregonus artedii), but it is unknown whether this arrangement of receivers, designed for offshore pelagic species, will also provide sufficient coverage to adequately detect the movement and habitat use of benthic species like suckers. The newly deployed receiver grid in Green Bay (GB) presents a unique opportunity to determine if a widely spaced array would be sufficient to elucidate the spatial ecology of suckers, with a focus on white suckers, as they have been the focus of a multi-year spawning site fidelity PIT tag study in the area, led by PI Murchie.

• Our specific objectives are to 1) determine the proportion of fish that were detected on the most western receivers in the SBC that were subsequently detected on grid receivers, 2) for fish that have entered the grid, determine the detection frequency, 3) determine the maximum movement distance and/or area of the receiver grid utilized and 4) determine if there would be a need to augment the grid to more effectively elucidate adult white sucker spatial ecology in future studies.

• Karen Murchie (Shedd Aquarium - Shedd Aquarium) - karen.murchie@gmail.com
• Dan Isermann (University Of Wisconsin Stevens Point)
• Dan Dembkowski (University Of Wisconsin Stevens Point)
• Ted Treska (United States Fish And Wildlife Service)
• Thomas Binder (Michigan State University)
• Pete Mcintyre (Cornell University)

• Shedd Aquarium - Shedd Aquarium
• University of Wisconsin Stevens Point
• United States Fish and Wildlife Service - Green Bay Fish and Wildlife Conservation Office
• Michigan State University
• Cornell University

• United States Fish and Wildlife Service - Green Bay Fish and Wildlife Conservation Office
• Great Lakes Fishery Commission
• Wisconsin Sea Grant
• University of Wisconsin Stevens Point
• Shedd Aquarium - Shedd Aquarium
• Great Lakes Acoustic Telemetry Observation System