Nests on large, shallow freshwater lakes and wetlands. Also nests on slow-moving streams in wooded, bushy, overgrown sites, or, less commonly, in concealed or bare sites in open tundra (NatureServe 2007b). High densities on lakes with densely vegetated (shrubs) islands. In Alaska, high densities on lakes and rivers within boreal forest zone.
NatureServe. 2007b. NatureServe Explorer: An online encyclopedia of life [web application]. Version 6.2. NatureServe, Arlington, Virginia. Available http://www.natureserve.org/explorer.