Monitoring wildlife in Ontario's lakes

Goal: To verify that acid rain controls protect aquatic habitats important for wildlife in Ontario and beyond.

The Canadian Wildlife Service (CWS) has studied the effects of acid rain on waterbirds and their habitats since 1980. Chemistry, food chains (fish, invertebrates) and waterbirds are monitored in 600 lakes in Muskoka, Sudbury and Algoma districts, including the Turkey Lakes Watershed (TLW). Lakes tend to be small (< 20 ha, often headwaters), range in acidity (pH), and often lack fish. In Algoma, small lakes and wetlands are poorly buffered against acidifying pollutants.

Common waterbirds include fish-eating species (Common Loon, Common Merganser), dabbling ducks (Mallard, Black Duck) and diving ducks (Hooded Merganser, Ring-necked Duck, Common Goldeneye). Effects of acid rain on waterbirds vary with their foraging habits and lake acidity. Adverse effects arise from shifts in habitat quality or diet, notably for fish-eating species.Some improvements in Algoma breeding habitats are predicted under existing Canadian and U.S. pollution control targets (2010) but further reductions are needed to protect and enhance the recovery of acid-sensitive lakes across Algoma.