To evaluate factors affecting recruitment of yellow perch Perca flavescens in southwestern Lake Michigan, a Ricker stock-recruitment model was fitted to age-0 abundance estimated from a fall bottom trawl survey (1989-2007) and spawning stock biomass estimates. Models were built for all possible combinations of four external variables: spring-summer water temperature, June nearshore zooplankton density, spring abundance of alewives Alosa pseudoharengus, and an index of wind-induced transport of yellow perch larvae. Four relatively parsimonious models were deemed robust, and three external variables were represented (spring-summer water temperature, spring alewife abundance, and June zooplankton density). The Ricker stock-recruitment model with the lowest value of Akaike's information criterion (i.e., the best-supported model) included spring-summer water temperature and spring alewife abundance. The basic Ricker stock-recruitment model ranked second, followed by the Ricker model that included June zooplankton density. The fourth Rickermodel that was deemed robust included spring-summer water temperature. The four best models provided a good fit to age-0 yellow perch abundance estimates based on fall seining catches along the Illinois shoreline of Lake Michigan during 1989-2007. Our findings indicate that over the last two decades, yellow perch recruitment benefited during years associated with relatively warm water, low alewife abundance, and high zooplankton density.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science