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<br />684 <br /> <br />sible that a substantial portion of the juvenile <br />salmonids consumed by northern squawfish be- <br />low McNary Dam were already dead. Thus, the <br />number of live juvenile salmonids consumed by <br />northern squawfish may be less than previously <br />assumed, suggesting that estimates of the impact <br />of northern squawfish predation on salmonid pop- <br />ulations should be adjusted. <br /> <br />Acknowledgments <br /> <br />We thank T. Olson, A. Murphy, and J. Petersen <br />for laboratory assistance, and J. Petersen, T. Poe, <br />M. Mesa, W. Nelson, E. Rockwell, and three <br />anonymous readers for reviewing the manuscript. <br />This work was funded by the Bonneville Power <br />Administration (contract DE-AI79-88BP91964) <br />and administered by W. Maslen. <br /> <br />References <br /> <br />Allan, J. D., and A. S. Aecker. 1988. Prey preference <br />in stoneflies: a comparative analysis of prey vul- <br />nerability. 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