Embryo and Larval Characteristics of Sauger, Walleye, and Their Reciprocal Hybrids

Abstract

Embryos and larvae of saugers, walleyes, and their reciprocal hybrids are described and compared. Sauger embryos and prolarvae, in contrast to walleye, are smaller and have less pigmentation. The yolk sac of a sauger is more oval than that of a walleye. Postlarval saugers and walleyes can be separated by characteristics of pigmentation, myomere counts, head length, and fin ray ossification. The number of pyloric caeca differentiates fish longer than 19 mm. Identification of larval hybrids is not possible since they closely resemble the female parent. Hybrids longer than 100 mm can be distinguished by their coloration pattern.