Michigan Department of Natural Resources Fisheries Technical Report No. 97-2, 1997

Use of Floy Tags to Determine Angler Harvest of Brown Trout in Two Southern Michigan Streams

Joseph M. Leonardi Michigan Department of Natural Resources Shiawassee District Office 10650 South Bennett Drive Morrice, MI 48857-9792

and

Michael V. Thomas Michigan Department of Natural Resources Lake St. Clair Fisheries Research Station 33135 South River Road Mt. Clemens, MI 48045

Abstract.–The 1992, 1993, and 1994 walleye Stizostedion vitreum spawning runs in the lower Huron River, a Michigan Lake Erie tributary, were surveyed using DC electrofishing equipment. A total of 1,573 walleye were collected during 52.6 hours of shocking, for a catch per effort of 29.9 walleye per hour. Annual population estimates for 1992, 1993, and 1994 were 3,424, 7,821, and 5,180, respectively. These were generated using the Schnabel method based on recaptures of tagged walleye. Females predominated, accounting for 55% to 68% of the catch annually. Visible signs of lymphocystis infection ranged from 10.2% to 17.9% of the fish examined. No walleye have been stocked in the lower Huron River. Age distribution indicated strong walleye year classes in 1985, 1986, 1990, and a poor year class in 1992. This pattern closely reflected documented strength and weakness of walleye year classes in Lake Erie. Collection of previously tagged fish indicates a portion of this population returns annually, suggesting a discrete stock. The dam and weir in the city of Flat Rock prevent walleye movement upstream. Stock assessment efforts on small tributaries, such as this one, will provide a broader understanding of walleye population dynamics in Lake Erie.

Fisheries Technical Report No. 97-2 - Full Text Acrobat Reader File.