SUMMER DISTRIBUTION, SURVIVAL, AND GROWTH OF JUVENILE COHO SALMON UNDER VARYING EXPERIMENTAL CONDITIONS OF BRUSHY INSTREAM COVER

Woody debris is an important feature of streams, and its presence and abundance have been correlated with the abundance, growth, and surviva l of juvenile salmonids. To investigate the proximate mechanisms linki ng brushy woody debris to salmonid fishes, we determined, over a 1-mon th period in summer, the spatial distribution of juvenile coho salmon Oncorhynchus kisutch introduced into an outdoor experimental stream co ntaining riffle-pool units that had one of four different levels of in stream brushy-debris complexity. We then equalized the fish density in each unit and monitored fish growth and survival over a 15-week perio d. Coho salmon distribution, growth, and survival varied greatly but w ere not consistently related to the complexity of brushy debris.