Fort Providence, Territoires-du-Nord-Ouest
Beaver Lake is the name for a wide part of the Mackenzie River where the river meets the western end of Great Slave Lake. Fort Providence, Northwest Territories is situated 20 kilometres downstream. Most of the land surrounding the lake is low-lying and underlain by shales and limestones. Big Island sits at the mouth of the Mackenzie River and so separates Beaver Lake (the river) into two channels, North and South. The north shores of these channels contain large areas of sedge-grass marshes, whereas narrower marshes line the south shores. Islands of the North Channel are generally low and marshy, but the islands of the South Channel are higher and often hold small spruce-poplar forests.
Tundra Swans and several species of ducks stop over in Beaver Lake during both spring and fall migration. Records from the autumn of 1972 show that 4,470 Tundra Swans were observed at this time, and in the spring of the following year, 1,175 were seen. The fall numbers equal about 2% of the current North American Tundra Swan population. This percentage may actually be higher because the overall population of the species has grown in recent years.
In the fall, roughly double the number of ducks (approximately 10,000) use the area as do in the spring (approximately 5,000). The most common species are Canvasback, American Wigeon, Mallards, and the scaup species. On one occasion, 8,000 Canvasbacks were seen in the North Channel. This is about 1% of the global population of the species.
Several potential industrial activities could lead to problems for waterfowl in the Beaver Lake area. Barges are a major mode of transport along the Mackenzie River and dredging is sometimes done to enable barge traffic to move with greater ease. This could be a source of disturbance if it is done during peak migration time. Secondly, a proposal has been put forward to dam Slave River (which feeds into Great Slave Lake) and this could influence the water levels at Beaver Lake (the outlet of Great Slave Lake). A final concern is the possibility that a set of transmission wires may be installed by the Northwest Territories Power Corporation over the river near Fort Providence. Overhead utility lines near wetlands in other locations have caused waterfowl mortality.Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
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