CA115
Stuart, Tachie and Middle Rivers


Site description (2001 baseline):

Site location and context
The Stuart, Tachie and Middle rivers are a series of connected rivers in north-central British Columbia. Middle River (at the north end) is joined to the Tachie River by Trembleur Lake, and Stuart Lake lies between the Tachie and Stuart rivers. This IBA is in three separated pieces of 30, 20 and 40 kilometres representing respectively the Middle River, Tachie River and part of the Stuart River. The town of Fort St. James is located at the junction of Stuart Lake and Stuart River and marks the northern end of the Stuart River portion. The gravel-bottomed Stuart River is the narrowest of the three rivers and fastest flowing, while the silty-bottomed Middle is wider and fairly slow moving. The rivers all discharge from large lakes, and so do not typically freeze in winter. Chinook Salmon spawn in the Stuart River.

Key biodiversity
This Important Bird Area supports globally significant numbers of wintering Trumpeter Swans. Throughout the 1990s, 500-550 swans wintered on these three sections of river. This represents about 2.5% of this species' global population, and is the northern-most population of wintering Trumpeter Swans. Swans have been wintering at this site for hundreds and perhaps thousands of years.

Conservation responses/actions for key biodiversity
There are no immediate threats to the future of this wintering population of Trumpeter Swans. The major source of mortality is caused by extreme cold. During colder than average winters, more ice forms on the river thereby sealing off feeding areas. A forestry bridge built over the Middle River has also contributed to increased ice build up in that location. Additionally, some swans have died from flying into powerlines.

Dams that have been constructed on other rivers in the region have resulted in increased siltation in some areas. When rivers channels become shallower due to the accumulation of silt, food resources available to the swans are reduced and ice build-up is more common.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Stuart, Tachie and Middle Rivers (Canada). Downloaded from https://datazone.birdlife.org/site/factsheet/stuart-tachie-and-middle-rivers-iba-canada on 25/12/2024.