Light and Temperature Effects on Performance of Walleye and Hybrid Walleye Fingerlings Reared Intensively

Abstract

Abstract Growth, survival, and feed conversion of walleye (Stizostedion vitreum) and F1 hybrid fingerlings (walleye ♀ × sauger ♂, S. canadense) were compared under conditions of submerged and overhead lighting. We also compared these variables for the hybrids at 20 and 25°C. After 71 d, walleyes reared with submerged lighting were longer than walleyes reared with overhead lighting. Other differences in performance between light treatment groups for walleyes were not significant. The performance of the hybrids was unaffected by temperature or light regime. Hybrids were longer and heavier than walleyes when reared with overhead lighting, but not when reared with submerged lighting. Hybrids had better feed conversion than walleyes when reared with submerged lights, and higher survival in both light regimes. Growth differences between walleyes and hybrids found in the present study and in previous investigations were reduced with the use of submerged tank lighting. Submerged lights also reduced agitation of t...