Coastal wetlands of the Great Lakes are critical habitats for ecologically and economically important species. Such habitats are susceptible to various anthropogenic disturbances, and monitoring of fish communities in the natural and restored Great Lakes coastal wetlands has been increasingly important for ecological sustainability. In this study, comparison of fish communities in natural and restored coastal wetlands were based on fish composition and abundance data collected from the Big Island Wetland (BIW) Habitat Bank and the Durham Region Coastal Wetland Monitoring Project (DRCWMP). The BIW Habitat Bank serves as one of the offsetting measures to counterbalance residual impacts to fishes resulting from impingement and entrainment at the Ontario Power Generation (OPG) Pickering Nuclear Generating Station (PNGS) since 2013. The fish community data from boat electrofishing surveys in BIW for late summer (August to September) 2018-2020 were compiled with the data from DRWCMP in 2015-2020. Nine fish species (Black Crappie, Bluegill, Bowfin, Brown Bullhead, Common Carp, Largemouth Bass, Northern Pike, Pumpkinseed, and Yellow Perch) from a total of 33 Great Lakes coastal wetlands were included in the analysis. Principal component analysis (PCA) and correspondence analysis (CA) were performed to examine the relationships between the nine fish species and the 33 wetlands.
Results/Conclusions
The wetlands were grouped according to their geographic locations: the east group included the wetlands with longitude of 76°W to 77°W, and the west group included the wetlands with longitude of 78°W to 79°W. Principal component analysis (PCA) and correspondence analysis (CA) suggested that Brown Bullhead, Common Carp and Northern Pike were more likely to occur in the western group of wetlands. Small fish species, such as Pumpkinseed, Yellow Perch, Bluegill, Largemouth Bass and Black Crappie, occurred more frequently in the relatively young, restored wetland BIW, whereas Brown Bullhead and Common Carp were more likely to occur in the other wetlands. This study suggested that the restored BIW fish community is similar in composition and abundance to the surrounding natural wetlands, and such restored coastal wetlands show great potential in serving as valuable habitats for the Great Lakes fish communities.
