Using size spectra to assess production potential for fisheries in the Great Lakes

Thomas Evans, Lars Rudstam, Jim Watkins, Doran Mason (NOAA), Zacharias Feiner (Wisconsin DNR), Gary Sprules (Univ Toronto) (Funded by CIGLR – Cooperative Institute for Great Lakes Research)

 Changes in the structure of community size spectra have been suggested to operate as indicators for ecosystem change or function, but the necessary understanding of how the size structure of communities respond to major ecological change to create useful predictions based on size spectra shifts is lacking.  This research provides a mechanistic understanding of the effects of anthropogenic disturbance on size spectra across a range of ecosystems.  The opportunity to use the Great Lakes as a natural experiment allowed us to identify spatial heterogeneity in community size structure and its relationship to the taxonomic composition and diversity in aquatic systems.  In addition, freshwater size spectra are relatively understudied compared to their marine counterparts.

A paper on the size spectra analysis across all five Great Lakes was published in the Canadian Journal of Fisheries and Aquatic Science (Evans et al. 2022).