Factors Affecting Recruitment of Walleyes in Escanaba Lake, Wisconsin, 1958–1996

Abstract

Abstract We modeled recruitment variation of age-0 walleyes Stizostedion vitreum in Escanaba Lake, Vilas County, Wisconsin, to determine factors regulating their abundance. Abundance of age-5 and older walleyes (spawning population), variation in May water temperatures, and abundance of 152.4-mm total length and longer yellow perch Perca flavescens explained 89% of annual variation of age-0 walleye abundance from 1958 through 1995. Abundance of age-5 and older spawners accounted for 32% of the recruitment variation and indicated that maximum numbers of age-0 recruits were produced at low numbers of spawners (fewer than 1,000 individuals). The coefficient of variation of May water temperatures improved the model fit to 56% of recruitment variation and indicated that increased variation of May water temperatures greatly reduced recruitment. The abundance of yellow perch 152.4 mm and longer further improved the model fit to 78% of recruitment variation and also reduced recruitment, though not as much as vari...