Effect of food abundance on larval lake whitefish, Coregonus clupeaformis Mitchill, growth and survival

Abstract

The effect of food ration on larval lake whitefish, Coregonus clupeaformis, growth and survival was determined in the laboratory using brine shrimp as the test prey. In replicate experiments, larval whitefish were fed one of seven different rations of brine shrimp over a 25 day period. Statistically significant differences were found between larval growth and survival at each feeding level. Larvae fed to excess were 1.33 times as long and 2.80 times as heavy as those on the 1.8 zooplankton/fish (z/f) ration. No mortality was recorded until after day 15 of the experiment by which time all larvae had resorbed their yolk sac. Total mortality followed within 1 week for all feeding densities with the exception of the three highest (18 z/f, 32 z/f and excess rations) where total mortality equalled 90%, 12% and 0%, respectively.