AUTHORS: Andrew Briggs, Michigan Department of Natural Resources; Justin Chiotti, U.S. Fish and Wildlife Service; James Boase, U.S. Fish and Wildlife Service; Jan-Michael Hessenauer, Michigan Department of Natural Resources; Jeannette Kanefsky, Michigan State University; Brad Utrup, Michigan Department of Natural Resources; Todd Wills, Michigan Department of Natural Resources
ABSTRACT: The Michigan Department of Natural Resources (MDNR) and U.S. Fish and Wildlife Service (USFWS) have been conducting Lake Sturgeon surveys in the St. Clair – Detroit River System (SCDRS) since 1996. Over this period determining sex of Lake Sturgeon has been difficult as the primary method to determine sex has been expulsion of gametes, which rarely occurs (particularly for females). Recent advances in genetic methods have shown that sex of Lake Sturgeon can be determined from a tissue sample or fin clip through molecular sexing. MDNR and USFWS have collected pectoral fin rays from Lake Sturgeon for aging purposes since their surveys began and have stored them over the years, allowing for a portion of these fin samples to be clipped and used for molecular sexing. MDNR and USFWS combined to provide over 2,700 tissue samples to Michigan State University for molecular sexing with 53% of the Lake Sturgeon being classified as female. This presentation will examine if sex ratios differed by location within the SCDRS, how sex ratios change by length, and sex-specific growth rates of Lake Sturgeon.
