Connecting yellow perch early-life dynamics to angler harvest in southwestern Lake Michigan

Session: Great Lakes Fish Habitat Priorities Development, Implementation, and Adaptive Management (4)

Charles Roswell, Illinois Natural History Survey, [email protected]
Scot Peterson, Illinois Natural History Survey, [email protected]
Sergiusz Czesny, University of Illinois, Illinois Natural History Survey, [email protected]

Abstract

Poor recruitment of yellow perch (Perca flavescens) has led to low harvest success for anglers fishing Illinois waters of Lake Michigan in recent years.  Previous research suggests multiple confounding ecological factors can affect yellow perch recruitment.  Additionally, dramatic declines in Illinois yellow perch harvest over the last decade suggest ecosystem changes may be further limiting availability of yellow perch to anglers (via poor survival or changes in adult behavior).  We have a poor understanding of how variation in harvest is driven by various early-life mechanisms prior to recruitment, e.g., age-0 production versus growth through age-3 (age-3+ fish typically comprise most of the angler harvest).  We use 13 years of small-mesh gill net assessments in nearshore waters of Lake Michigan (CPUE, size-at-age of ages 0-2) to track year classes and examine drivers of subsequent angler success (assessed via harvest rate, size- and age-composition of harvest data from the recreational fishery).  Because angler harvest can be driven by factors beyond adult fish abundance (e.g., changes in habitat use), understanding the link between early life dynamics and subsequent harvest can help identify other ecosystem processes that are important to the fishery and can inform management.