Collaborative, Bi-national Fish Habitat Study Reaffirms the Importance of Wetlands, and Natural Shorelines in Promoting Abundant Bass and Bluegill populations

By December 8, 2021 News

The recently released summary of the findings of a bi-national fish study conducted on Lake St. Clair serves to emphasize the critical role that wetlands and other natural shoreline features play in promoting and sustaining healthy freshwater fish populations. Focusing on relatively small fish such as minnows, bluegill, and sunfish as well as the young of species such as largemouth and smallmouth bass that ultimately mature into much larger fish, the Collaborative Lake St. Clair Fishery Assessment was conducted by fisheries biologists from the Michigan Department of Natural Resources, Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry, and the U. S. Fish and Wildlife Service. The primary goal of the study was to help fisheries biologists understand how many of the small fish exist within the lake, and to also identify exactly what type of shoreline habitat serves to promote their abundance. The most important finding of the study is indicated by the fact that the keystone fish were found to be ten times more abundant in areas of the lake featuring nearshore and shoreline habitat consisting of wetlands, and other natural features in comparison to more urbanized areas on the Michigan side of the lake where shorelines now consist primarily of steel seawalls, piles of rock and concrete, and other forms of artificial shoreline armoring.

Even though Lake St. Clair possesses a surface area of only 430 square miles it is considered to be an important bi-national resource due to the fact that it is connected to Lake Huron by the St. Clair River, and to Lake Erie by the Detroit River, and is therefore considered one of the busiest waterways in the world due to the fact that 5,000 ships transit the lake each year on their way to and from commercial ports located within the expansive Great Lakes, and to locations far beyond the region via the St. Lawrence Seaway.

It is also important to note that Lake St. Clair’s remaining coastal wetlands, located primarily on the Ontario side of the lake, also provide critical habitat to a diverse array of fish, reptiles, migratory birds, and amphibians. The large inland lake also provides an array of highly valuable ecological, recreational, and commercial benefits, including drinking water, to millions of people who live on or near the lake in southeast Michigan and southern Ontario.

Conducted on both the Michigan and Ontario sides of Lake St. Clair, fisheries biologists deployed fyke nets at 110 locations around the lake in areas defined by both hardened and natural shorelines, and recorded both the quantity and type of fish that swam into the nets. Reporting the findings of their study within the context of a written summary recently submitted to The Detroit News, the fisheries biologists wrote that “the overall fish catch rate was 10 times higher on the Canadian side of the lake, likely related to better nearshore habitat.” In sharp contrast to hardened shorelines comprised of seawalls or piles of concrete, natural shorelines and nearshore habitat comprised of emergent, floating, and submerged aquatic plants such as cattails, bulrush, water lilies, and pondweeds provide small fish such as bluegill and young bass with an ideal habitat within which to forage for abundant aquatic insects, protection from predation, and an ideal habitat for spawning and supporting young fish.

To learn more about the multi-faceted benefits of preserving, and/or restoring natural shorelines, visit the Michigan Natural Shoreline Partnership at https://www.mishorelinepartnership.org/ .