Bollens et al.: Feeding ecology of juvenile Oncorhynchus spp. 
405 
derstand species-specific responses to resource and en- 
vironmental variability. Our results from Dabob Bay 
indicate that periodic high diet overlap between salmon 
species may occur. However, evidence of resource parti- 
tioning, especially between frequently co-occurring spe- 
cies (e.g., chum and Chinook salmon), combined with a 
lack of evidence for food limitation (although this should 
be more explicitly tested in the future), indicates that 
competition between juvenile salmon is unlikely to oc- 
cur in this marine fjord. 
Acknowledgments 
We thank D. Thoreson, S. Jonasdottir, C. Mobley, and 
the crew of the RV Barnes for assistance with field work, 
W. Peterson for assistance with zooplankton analyses, 
and J. Breckenridge and J. Emerson for assistance with 
graphics. R. Brodeur and three anonymous reviewers 
provided comments that substantially improved the 
manuscript. Special thanks go to S. Simenstad and 
K. Fresh for helping a young oceanography graduate 
student bridge the gap between fisheries and biological 
oceanography. We also thank the University of Otago’s 
Departments of Zoology and Marine Sciences for provid- 
ing office space and other support to S. Bollens during 
the writing of this article. This research was supported 
by National Science Foundation grant 84-08929 to B. 
Frost, and Washington State University institutional 
funds (including a sabbatical leave) made available to 
S. Bollens. 
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