Midwest Fish & Wildlife Conference 2019

AUTHORS: Curtis P. Wagner, Kevin S. Page – Ohio Division of Wildlife

ABSTRACT: Muskellunge fisheries in Ohio are maintained through stocking.  The Ohio Division of Wildlife (ODOW) stocks approximately 20,000 advanced-fingerling (10–12 inches) Muskellunge annually among nine reservoirs (1 fish/acre).  Currently, voluntary angler reports of Muskellunge catches provide managers with information on the locations, numbers, sizes, and harvest of Muskellunge.  However, this voluntary reporting approach potentially misses critical information on population dynamics metrics such as survival, escapement, and the probability of catching a fish.  To provide additional information on which to evaluate Muskellunge population dynamics in Ohio, the ODOW initiated a long-term tagging study.  Starting in 2013, all Muskellunge stocked into four study reservoirs (>43,000) have been implanted with passive integrated transponders (PIT).  Escapement of Muskellunge is monitored using in-stream PIT detection systems stationed within dam spillways.  Anglers report in-reservoir recaptures using handheld PIT tag readers.  To date, more than 850 implanted Muskellunge have been detected or reported. Focusing on the escapement component of the study, we found that escapement of Muskellunge appears to vary seasonally and depend on the type of dam water control structure.  For one reservoir, the probability of escapement was 4 – 36%, annually.  Together, these estimates provide a more comprehensive picture of Muskellunge fisheries in Ohio reservoirs.

AUTHORS: Robert Sheffer, Wisconsin Cooperative Fishery Research Unit, University of Wisconsin-Stevens Point; Daniel Dembkowski, Wisconsin Cooperative Fishery Research Unit, University of Wisconsin-Stevens Point; Steven Hogler, Wisconsin Department of Natural Resources; Joshua Raabe, University of Wisconsin-Stevens Point, Daniel Isermann, U.S. Geological Survey, Wisconsin Cooperative Fishery Research Unit, University of Wisconsin-Stevens Point

ABSTRACT: Green Bay and its tributaries support a world-class fishery for trophy muskellunge that attracts anglers from across North America. The Lower Fox River and Green Bay muskellunge population is largely supported by stocking because natural recruitment is limited, possibly due to habitat limitations. While previous work has identified potential spawning locations, it is unknown whether muskellunge hatch at these locations and habitat attributes associated with successful hatching have not been determined. Our objectives are to: 1) determine the proportion of muskellunge spawning in tributaries to lower Green Bay or in Green Bay proper; 2) determine the proportion of adults that return to stocking locations to spawn; 3) determine if muskellunge return to the same spawning locations in consecutive year; 4) define habitat conditions that result in successful hatching and 5) characterize general movement patterns of muskellunge. We will identify spawning sites of tagged muskellunge (N = 60) using radio and acoustic telemetry and conduct spawning habitat surveys. Presence or absence of eggs and larvae at spawning sites will be used to develop predictive maps of suitable habitat throughout the Green Bay ecosystem.