Evidence of interactions between walleye and yellow perch in New York State lakes

Walleye (Stizostedion vitreum vitreum) and yellow perch (Perca flavescens) co-occur in many central North American lakes and often form a tightly coupled predator-prey species pair (Forney 1980, Post & Rudstam 1992). Our current understanding of these species’interactions is based partly on long term studies in Oneida Lake, New York, by John Forney and co-workers (e.g. Forney 1976, 1977, 1980, Mills & Forney 1988). When walleye are abundant (as in Oneida Lake), they are the main predator on youngof-year yellow perch (YOY perch). YOY perch are vulnerable to walleye predation once they reach a total length of 18 mm and walleye often consume a large portion of the YOY perch population during Ann. Zool. Fennici 33: 443–449 ISSN 0003-455X Helsinki 28 November 1996 © Finnish Zoological and Botanical Publishing Board 1996