Michigan Department of Natural Resources
Research and Development Report
No. 233
Fisheries Research Report No. 1776, 1971
Salmon Eggs as Food for Stream Salmonids and Sculpins
Thomas M. Stauffer
Introduction.-Coho salmon, Oncorhynchus kisutch, were successfully introduced into the Great Lakes in 1966. Since then, annual plants have been increased to an expected 4.5 million yearling coho salmon in 1971. Survival of salmon to maturity has been excellent, and many planted streams have been the scene of extensive spawning by coho salmon. In addition, straying of planted salmon was widespread and spawning occurred in other streams (Peck, 1970). Extensive spawning by adult salmon in many trout streams has caused much concern about the effect of this activity on brown trout (Salmo trutta), brook trout (Salvelinus fontinalis), and rainbow trout (Salmo gairdneri).
Hildebrand (1971) has shown that fall-spawing coho salmon decimate the bottom organisms that serve as food for trout, with little recovery at least until the following May. On the other hand, it has been postulated that salmon are beneficial to stream trout because salmon eggs provide a source of food. My objective here is to ascertain the extent that salmon eggs are utilized as food by small salmon, trout, and slimy sculpins (Cottus cognatus).