Lakes, Loons and Water Quality in Nova Scotia

by Benna Keoghoe

Common Loon enjoying some peace and quiet in Southwest Nova Scotia. Photo by Brennan Caverhill.

Nova Scotia is home to a marvelous network of freshwater lakes, perfect for summer swims, autumn canoeing, and for skating on a frosty winter day. They are also habitat for some of our favourite wildlife, including the iconic Loon.

As the lake ice melts in early spring, Common Loons (Gavia immer) return from the ocean to find a place to raise their young. To most of us the Loon is a symbol of the Canadian wilderness, with their striking size, distinctive appearance and their haunting calls which echo across vast landscapes. An adult Loon in summer plumage has a large black head with a sharp dagger-like black bill and red eyes. A ring of white lines surrounds its black neck like a necklace, and its back displays a pattern of black and white, like a checkerboard.

Scientists and naturalists are concerned about Nova Scotia’s Loons. Volunteers and staff with Bird Studies Canada, Parks Canada, Environment Canada and the Mersey Tobeatic Research Institute near Kejimkujik National Park in Queens County are currently monitoring breeding loon populations.

Many of Nova Scotia’s lakes are naturally acidic (with low pH), due to slightly acidic rain and the area's geology and soils. However, humans have been adding to the acidity- most of it originating from factory emissions as far away as Ontario or the northeastern United States. This acidity increases the amount of heavy metals, such as mercury, found in the flesh of lake fish, along with the loons that eat the fish. What hasn't been determined so far is exactly how the increased mercury levels are affecting the Loons.

There are a variety of other threats facing loons. For example, these birds can be very sensitive to human disturbance, especially during breeding season, which runs from late May to the end of August. Lakes inhabited by Loons around the province also tend to attract people for a variety of recreational activities. Boat wakes can flood nests and lakeside development that doesn't leave a vegetative buffer can also destroy nesting habitat.

To avoid disturbing Loons during breeding season, have a look around a lake before engaging in potentially disturbing activities. If a pair of Loons is present then there is a good chance that they have a nest. Be considerate and give them a little space. If you do own property on a lake, consider leaving or restoring a healthy buffer of vegetation along the shore.

If you'd like to volunteer to monitor loons in Kejimkujik or on your own lake, contact Bird Studies Canada or the Mersey Tobeatic Research Institute (902-682-2371). LoonWatchers receive a form that can be filled out through the summer to record loon activities. At the end of the season, your information is collected and used to help protect Nova Scotia’s loon populations.

Benna Keoghoe is studying wildlife conservation at the University of Plymouth, and worked as part of the Loon research team at MTRI during the summer of 2008. Coastlines is coordinated by the Coastal Issues Committee at Ecology Action Centre and supported by the Nova Scotia Habitat Conservation Fund with contributions from hunters and trappers.