The health of Lake St. Clair and the Sydenham River is under threat and needs to be protected.
That's according to the Nature Conservancy of Canada (NCC).
Its report shows primary threats to these freshwater Key Biodiversity Areas (KBAs) are changes in natural flows from dams, water pollution from agriculture and urbanization, overuse of surface and ground waters, and competition with invasive species.
The NCC says Lake St. Clair has two species of threatened mussels that must be protected, adding that invasive species have led to the decline of these native mussels in the Great Lakes region. But recent surveys have found the species in considerable abundance in Lake St. Clair.
The report also shows almost 85% of the Sydenham River's basin is now agricultural and wetland cover is less than 1%.
Five globally threatened mussel species have been found there and threats include sedimentation (mainly from agriculture), reduced flow and downstream erosion from dams, nutrient loading from agriculture and urban runoff, and invasive species, including zebra and quagga mussels.
"Our freshwater ecosystems are under threat in Canada," says Dan Kraus, Nature Conservancy of Canada senior conservation biologist and co-author of the report. "Across southern Canada, we are continuing to lose freshwater habitats, such as wetlands, and altering the water quality and flow patterns of rivers and streams. In many settled parts of Canada, more than half of the wetlands have been lost, and we are seeing an increase in nutrient runoff that is polluting our lakes. Protecting freshwater habitats is important for saving these globally rare species, but also critical for people.
“By protecting these KBAs, we are protecting places that are not just important for Canada, but also important for global nature conservation,” says Kraus.