Great Slave Lake - Geography and Natural History

Geography and Natural History

The Hay, Slave and Taltson Rivers are its chief tributaries. It is drained by the Mackenzie River. Though the western shore is forested, the east shore and northern arm are tundra-like. The southern and eastern shores reach the edge of the Canadian Shield. Along with other lakes such as the Great Bear and Athabasca, it is a remnant of the vast Glacial Lake McConnell.

The East Arm of Great Slave Lake is filled with islands, and the area is within Thaydene Nene National Park. The Pethei Peninsula separates the East Arm into McLeod Bay in the north and Christie Bay in the south. The lake is at least partially frozen during an average of eight months of the year. During winter, the ice is thick enough for semi-trailer trucks to pass over using ice roads. Until 1967, when an all-season highway was built around the lake, goods were shipped across the ice to Yellowknife, located on the north shore. Goods and fuel are still shipped across frozen lakes up the winter road to the diamond mines located near the headwaters of the Coppermine River, Northwest Territories. A ferry is required to reach Yellowknife when the ice is not present in a solid sheet along Highway 3 where it crosses the Mackenzie River. The ferry usually runs from mid-May until January with a three to four week period (from mid-April to mid-May) between the closing of the ice road and the start of ferry service. However, the expected completion of the Deh Cho Bridge across the Mackenzie in 2012 is expected to end the need for the ferry.

The main western portion of the lake forms a moderately deep bowl with a surface area of 18,500 km2 (7,100 sq mi) and a volume of 596 km3 (143 cu mi). This main portion has a maximum depth of 187.7 m (616 ft) and a mean depth of 32.2 m (106 ft). To the east, McLeod Bay (62°52′N 110°10′W / 62.867°N 110.167°W / 62.867; -110.167 (McLeod Bay, Great Slave Lake)) and Christie Bay (62°32′N 111°00′W / 62.533°N 111°W / 62.533; -111 (Christie Bay, Great Slave Lake)) are much deeper, with a maximum recorded depth in Christie Bay of 614 m (2,014 ft).

On some of the plains surrounding Great Slave Lake, climax polygonal bogs have formed, the early successional stage to which often consists of pioneer Black Spruce.

South of Great Slave Lake, in a remote corner of Wood Buffalo National Park, is the nesting site of a remnant flock of Whooping Cranes, discovered in 1954.