White Perch Expansion and Life History Within a Southern Reservoir

Abstract

Concern has been raised regarding the effects of invasive fishes, among them white perch (Morone americana), in a variety of freshwater systems. Previous research on white perch as an invasive species has examined landlocked white perch in ponds, lakes and reservoirs throughout much of its geographic range. However, research has been lacking regarding the role of invasive white perch in southern reservoirs. A long-term data set of the Jordan Lake fish community indexed via gill nets was evaluated to assess the expansion of white perch in Jordan Lake, as well as concurrent declines in other fishes found in Jordan Lake from 1987 through 1998. White perch catch rates increased from zero fish per net night in 1987 to 16.1 fish per net night in 1994, surpassing catch rates for all other fish captured in gill nets. White perch were found to live to age 7 in Jordan Lake where they shift food habits seasonally from zooplankton and diptera larvae in the spring to young shad in the fall. Relative weights and mean calculated total lengths at annulus formation suggest that the Jordan Lake white perch population is in good condition, comparable to other landlocked white perch populations in North Carolina and surpassing white perch populations found in their native estuarine environs throughout the eastern seaboard. Young white perch were found to prefer cover-free primary points featuring hard sand and clay substrates, minimizing the likelihood that Jordan Lake white perch will impact centrarchids as has been suggested by research in other freshwater systems outside of the southeastern United States.