Influence of Sand in Redds on Survival and Emergence of Brook Trout (Salvelinus fontinalis)

Abstract

Alevins of brook trout (Salvelinus fontinalis) were buried in laboratory troughs in spawning gravel containing 0 to 25% sand. Sand slowed emergence and reduced the number of fry emerging. Weight of fry was not related to proportion of sand in the gravel, but was related to time; the fry were heaviest near the time of peak emergence, and lighter before and after the peak. Survival was estimated to be 84% from egg deposition to hatching for brook trout in Lawrence Creek, Wisconsin, and 70% from hatching to emergence, providing a total estimate for survival from egg deposition to emergence of 59%.