Cooperative Fish and Wildlife Research Units Program: Wisconsin Fishery
Education, Research and Technical Assistance for Managing Our Natural Resources

Wisconsin Fishery Project

Spatial variation in lake whitefish recruitment in Lake Michigan: the potential roles of zooplankton prey and the relative fitness of age-0 fish

January 2021 - December 2022


Participating Agencies

  • Great Lakes Fish and Wildlife Restoration Act

Lake whitefish support the most economically-important commercial fishery in the Great Lakes and they also support important tribal and recreational fisheries in many areas throughout the basin. In Lake Michigan, many lake whitefish stocks have experienced declines in recruitment. However, at the same time, lake whitefish in some areas of the lake have shown signs of increasing recruitment and expansion. Contrasting trends in recruitment complicate fisheries management and understanding the factors regulating spatial variation in recruitment is critical to implementing appropriate management actions that ensure the sustainability of all stocks. Our project will address whether spatial variation in lake whitefish recruitment may be related to spatial variation in productivity, the availability of zooplankton prey, and the relative fitness of age-0 lake whitefish. This project is a collaboration of researchers across multiple agencies involved with lake whitefish management in Lake Michigan and includes representatives of the USGS Wisconsin Cooperative Fishery Research Unit, the University of Wisconsin-Stevens Point, Wisconsin and Michigan Departments of Natural Resources, the Sault Ste. Marie Tribe of Chippewa Indians, and the National Oceanic and Atmospheric Administration. Our research will directly address research priorities outlined in Wisconsin and Michigan Departments of Natural Resources fishery and wildlife management plans. Our findings will help fishery managers and researchers identify factors contributing to spatial variation in lake whitefish recruitment in Lake Michigan and determine if adjustments to harvest regulations are needed (including spatial reallocation of harvest quotas), design spatially explicit monitoring protocols for lower trophic levels, and better manage expectations of policy makers and stakeholders.