Great Lakes Fishery Commission

Updated 2024-12-11 00:04:51

Lake Huron -> 2.0 Percid (Walleye and Perch) -> Walleye Total Length

2.1.3. Mean total length at age 3 (sexes combined) equal to 110% of state average.

This metric was developed as one criteria to gauge recovery of Walleye in Saginaw Bay. Because the habitat and ecology of the bay has changed over time, it is unclear if past yield can be a reasonable goal for recovery. The use of growth rate is an attractive alternative because growth rate is density dependent (fast growth when Walleye are scarce and slower growth when Walleye are abundant because  of greater competition). Consequently, growth rate can be a surrogate for where the Walleye population is with respect to ‘carrying capacity’ (amount of prey and habitat). Prior to 2003, Saginaw Bay Walleye grew very fast, about 127% of the state average rate. A recovery target was crafted indicating that the Walleye population goal was to increase in abundance such that the growth rate would come down to 110% of the state average rate. After Walleye reproductive success increased in 2003, growth rate did decline and the formal objective defined for recovery was first met in 2009. This metric continues to be tracked as a useful gauge to assess where the bay’s Walleye population is at relative to the available prey and habitat.

Walleye total length by year in Saginaw Bay, Lake Huron.