Year-Class Formation in the Walleye (Stizostedion vitreum vitreum) Population of Oneida Lake, New York, 1966–73

Abstract

Abundance of eight successive year-classes of walleyes (Stizostedion vitreum vitreum) was measured at intervals from hatching into the second year. Each year-class arose from an initial stock of 12–18 billion eggs. Population of pelagic larvae was augmented in some years by the release of hatchery-reared larvae but the effect on year-class size was obscured by mortality after young became demersal. Decrease in number of fingerlings was attributed to predation by older walleyes. Intensity of predation was influenced by abundance of alternate prey and duration of cannibalism by growth of young walleyes. Five year-classes that were monitored through age 4 contributed 12,000–478,000 walleyes to the adult stock.