Dubawnt Lake, 3833 km2, elevation 236 m, is situated in the southern part of mainland Nunavut, 350 km south of the Arctic Circle. Within the Precambrian Shield, the lake has irregular shorelines and numerous islands. It is drained northward by the Dubawnt River into Aberdeen Lake, then eastward by the Thelon River into Hudson Bay. Its water is clear and deep. Lake trout, lake and round whitefish and arctic grayling are common in the lake. The surrounding slopes consist of glacial till, festooned by the abandoned beaches of a proglacial lake up to 73 m above the present water level. The vegetation is low arctic tundra with heath and lichens, although scattered groves of stunted spruce occur at the south end. The lake is on the migration route of the Qamanirjuaq caribou herd, consisting of over 500 000 animals. Muskoxen occur in the area, especially to the west, within the Thelon Game Sanctuary. Wolves, foxes and grizzly bears are the main predators. The lake is at the contact point between the Chipewyan and inland Inuit, but there are no permanent settlements here. The lake was discovered by Samuel Hearne in 1770, but remained virtually unknown until explored by Joseph B. Tyrrell in 1893.