Hatching Success of Lake Whitefish Eggs in Heated Water

Eggs of lake whitefish (Coregonus clupeaformis) were first incubated at 0.5 to 8°C and then, for the last half of development, at 8 and 10°C. Provision of higher temperatures for the last half of the incubation period resulted in hatching success of more than 85% with less than 6% abnormal fry, in contrast to earlier studies that found 10°C harmful when used for the entire incubation period. The harmful effects of incubation at 10°C evidently occur during the early stages of development.