Response of yellow perch (Perca flavescens) in Oneida Lake, New York, to the establishment of zebra mussels (Dreissena polymorpha)

We used long-term data on Oneida Lake, New York, to evaluate hypotheses abo ut the effects of introduced zebra mussels (Dreissena polymorpha) on yellow perch (Perca flavescens). We detected no change in survival, diet, or numb ers of young-of-the-year (YOY) yellow perch. YOY growth increased in associ ation with zebra mussel introduction and was marginally correlated with zoo plankton size, which increased after zebra mussel introduction. Low numbers of YOY in recent years did not explain their increased growth rate. The pe rcentage of age 3 and older yellow perch that consumed zooplankton and bent hos increased after zebra mussel introduction. Water clarity, which has inc reased since zebra mussel introduction, was inversely related to the percen tage of the adult population with empty stomachs and positively related to the percentage that consumed benthos. The percentage of adult yellow perch that consumed zooplankton was positively related to zooplankton size. Despi te the increase in percentage of adults consuming both types of invertebrat e prey, we detected no changes in adult growth associated with zebra mussel introduction. This suggests that the principal effects of zebra mussels on yellow perch in Oneida Lake were not via benthic pathways but through modi fications of water clarity and zooplankton. Thus far, these effects have no t been negative for the yellow perch population.