Density-Dependent Growth of Yellow Perch in Southern Lake Michigan, 1984–2004

Abstract

The relationship between the growth rates and abundance of yellow perch Perca flavescens was evaluated in the Indiana waters of Lake Michigan from 1984 to 2004. Relative abundance values were taken from trawl catch per unit effort, while growth rates were determined by back-calculation. Abundance was approximately one order of magnitude higher during the mid-1980s than in 1990–2004. Growth rates were negatively related to relative abundance and were sexually dimorphic (females grew faster than males). Regression analysis indicated that approximately one-half of the observed variation in growth was related to abundance; this was most apparent with smaller and younger fish. Lee's phenomenon was shown to be present during periods of high exploitation and not present during periods of low exploitation. Both intraspecific competition and physiological changes associated with age at maturity are plausible explanations for these relationships.