Coastal Wetland Support of Great Lakes Fisheries: Progress from Concept to Quantification

Abstract

Fishery support is recognized as a valuable ecosystem service provided by aquatic systems, but it is harder to quantify than to describe conceptually. In this paper, we combine data on fish inhabiting Great Lakes coastal wetlands (GLCWs) with information on commercial and recreational harvest and the piscivore forage base to develop quantitative understanding of the multiple species involved in direct and indirect fishery support of this complex fishery. We then examine patterns of species co-occurrence and life history and relationships to GLCW conditions in order to identify fishery support metrics useful in aggregating species patterns and evaluating management outcomes. Our criteria for wetland prevalence (≥10% occurrence) and fishery importance (≥1% of recreational or commercial harvest in one or more of the Great Lakes or having a major forage fish role) yielded 21 wetland-using, fishery-relevant species representing multiple taxonomic groups and life history attributes. Wetland-using species are estimated to make up half the biomass and 60% of the dollar value of the fish landed commercially and ∼80% of the fish numbers harvested recreationally. All of the GLCWs studied supported species of interest to recreational and commercial fishers but with widely varying composition. A few key habitat characteristics (e.g., vegetation structure) are broadly predictive of the types of sport and panfish present, with more degraded GLCWs generally supporting abundant but lower-value taxa (rough-fish species) and less degraded GLCWs supporting fewer but higher-value taxa (sport and panfish species). No single taxonomic or functional metric seems adequate to capture the diversity of fishery-relevant species supported by GLCWs; fishery support needs to be understood and managed in a multimetric context.

Received May 16, 2014; accepted October 15, 2014

ACKNOWLEDGMENTS

We thank Michael Sierszen, John Brazner, David Jude, Edward Rutherford, and Don Schreiner for conversations that helped shape our thinking; staff from various fish management agencies for helping locate data reports; and the MED coastal wetland team for generating fish composition and habitat data. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency.