Sex ratios of young-of-the-year walleye (Stizostedion vitreum) collected from lakes and rearing ponds of western Canada and northern United States

Abstract

A total of 2682 young-of-the-year walleye (Stizostedion vitreum) were examined from 26 culture ponds and 5 large lakes to determine whether the sex ratio of cultured populations deviated from 1:1. Fingerlings from the lake populations were examined as a standard for comparison. Application of a χ2 test to pond data indicated that ponds, as a group, had significant deviations. Three of the ponds produced significantly more females and two of the ponds produced significantly more males. Neither the grouped nor the individual data from lakes produced sex ratios that deviated significantly from 1:1. Environmental factors such as pond size, depth, stocking rates, or time did not seem to influence sex determination.