Scott Island Group

Site description (2001 baseline):

Site location and context
The Scott Islands are a group of five islands extending in a line westward from 10 to 46 km offshore of Cape Scott at the northwestern tip of Vancouver Island. The inner two islands, Cox and Lanz, are large forested islands, whereas the outer two, Triangle and Sartine, are completely treeless. Beresford, the smallest island, lies in the middle of the chain and exhibits transitional features.

Key biodiversity
The Scott Islands support the largest concentration of breeding seabirds in the eastern North Pacific south of Alaska, and are the most important breeding colonies for seabirds in British Columbia. Twelve species of seabirds breed in this group of islands, with virtually all the nesting occurring on Triangle, Sartine and Beresford Islands. Together these Islands support over two million breeding birds.

Three of the seabird species nesting on the islands occur in globally significant numbers (i.e., greater than 1% of their population). These species are: Cassin?s Auklet (as much as 55% of the global, and 73% of the national population); Rhinoceros Auklet (as much as 7% of the global, 9% of the continental, and 12% of the national population); and Tufted Puffin (2% of the global, and almost 90% of the Canadian population). Other species that are present in at least nationally significant numbers (i.e., greater than 1% of the national population) include: Fork-tailed Storm-Petrel (1.5% of the Canadian population), Leach?s Storm-Petrel (2.3% of the western Canada population), Pelagic Cormorant (just over 1% of the North American, and 17.5% of the Canadian population), Brandt?s Cormorant (40% of the Canadian population) Black Oystercatcher (almost 3% of the Canadian population), Glaucous-winged Gull (about 4% of the national population), Common Murre (as much as 95% of the western Canada population) and Pigeon Guillemot (6% of the national population).

Other species of seabirds nesting on the islands include Thick-billed Murre (the only known site in Canada where the Pacific population nests) and Horned Puffin (less than 25 pairs in British Columbia). The marine areas surrounding the islands are important feeding areas for the nesting seabirds as well as other marine birds such as Sooty Shearwaters. Large numbers of migrating and wintering seaducks such as White-winged Scoters also frequent the area, particularly in the vicinity of Cox and Lanz islands.

Triangle Island supports several pairs of Peregrine Falcons (ssp. pealei ) a species considered nationally vulnerable. Peregrine Falcons are also recorded at each of the other four islands in the group and Bald Eagles nest throughout.

Conservation responses/actions for key biodiversity
The primary threats to the area are potential oil spills, and possible disturbance from boaters. During the late 1930s, mink and raccoon were introduced to Lanz and Cox islands. It is thought that their subsequent population explosion caused the extirpation of the Cassin?s and Rhinoceros Auklets colonies that were probably there. The spread of predators (raccoons and mink) to the outer islands has not occurred, and is not thought likely to pose a threat, because of the distance between them and the inner two islands.

Beginning in the mid 1970s, Triangle Island has been a site for seabird ecological studies sponsored by the Canadian Wildlife Service. It is now the site of a research station sponsored by the Canadian Wildlife Service/Simon Fraser University NSERC Wildlife Ecology Chair.

Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Scott Island Group. Downloaded from on 28/02/2024.