Prediction of Walleye Egg and Embryo Survival at Two Stages of Development

Abstract

Abstract Survival of the eggs and embryos of walleye Stizostedion vitreum from fertilization through the eye-up stage just prior to hatch was determined at approximately 6, 72, and 180 h postfertilization—3, 45, and 112 temperature units (TU = days × °C above 0°C). Mean survival was 58.5% at 6 h, 50.3% at 72 h, and 49.9% at 180 h. Eighty-three percent of the total egg mortality occurred prior to 6 h. Survival was significantly different (P = 0.0052) only between the 6-h and 180-h estimates. A predictive equation was calculated for survival from 6 h to 180 h: percent survival at 180 h = 5.4997 + 0.7596 × percent survival at 6 h; R 2 = 0.597, P < 0.0001. This equation, used in conjunction with techniques described in this paper, can provide estimates of walleye egg survival early in the incubation period, which can save time and effort in both research and large-scale production.