Russell K. Wong, Richard L. Noble, James R. Jackson, Department of Zoology, Campus Box 7617, NC State University, Raleigh, NC 27695-7617, and Scott L. Van Horn, NC Wildlife Resources Commission Falls Lake Office, 1142 I-85 Service Road, Creedmore, NC 27522

Abstract. White perch (Morone americana) are opportunistic feeders capable of early maturation, high fecundity and indiscriminate broadcast spawning at early spring temperatures. These characteristics enable white perch to invade lentic freshwater systems where juveniles occupy the littoral zone and adults the limnetic. We documented the invasion and community impacts of white perch in Jordan Lake through lakewide gillnet catches of adults and shoreline electrofishing of juveniles. Adult white perch catches increased almost exponentially from 1990-95. Concurrent increases in relative abundance of juveniles were recorded until 1997 when a year-class failure reduced juvenile abundance to pre-1991 levels. Diet analysis indicates that young-of-year white perch in Jordan Lake are zooplanktivorous and insectivorous in spring, shifting primarily to insectivory in summer. White perch remain insectivorous through several growing seasons until they exceed 200 mm at which time juvenile shad and bluegill begin to appear in their diets. However, white perch in Jordan Lake remain predominantly insectivorous unlike other freshwater populations of adult white perch. We hypothesize that this failure to shift to piscivory is responsible for the low condition of white perch adults in Jordan Lake.