Chapter 20: Individual-Based Model Analysis of Walleye and Yellow Perch Population Dynamics in Response to Changing Ecosystem Conditions
Edward S. Rutherford and Kenneth A. Rose
Walleye Sander vitreus and Yellow Perch Perca flavescens are the dominant predator and prey species in Oneida Lake and support a valuable recreational fishery. Abundances of both species have fluctuated greatly over time due to changes in weather and alterations in food web dynamics resulting from species irruptions and invasions of exotic species. At least one major ecological perturbation has impacted the Oneida Lake ecosystem in each decade since scientific monitoring of the lake began in the late 1950s, and some changes have occurred simultaneously. Although the population dynamics of Walleyes and Yellow Perch in Oneida Lake have been well documented (reviews in Forney 1980; Mills and Forney 1988; Rudstam et al. Chapter 15), recent coincident invasions by zebra mussels Dreissena polymorpha that affect lower trophic levels (Idrisi et al. 2001; Mayer et al. 2000), and irruptions of double-crested cormorants Phalacrocorax auritus that prey on upper trophic levels (Rudstam et al. 2004) have complicated interpretation of factors influencing percid population dynamics.