Scott Islands IBA Area

Posted April 26, 2013 | Categories : 11,12,13,Reports |
IBA Scott Island Group
Northern Vancouver Island, British Columbia
Site Summary
BC006 Latitude
50.823° N
128.825° W
0 – 312 m
1186.72 km²
coniferous forest (temperate), open sea, coastal cliffs/rocky shores (marine)
Land Use:
Not Utilized (Natural Area)
Potential or ongoing Threats:
Introduced species, Other increased mortality, Oil slicks
IBA Criteria: Globally Significant: Congregatory Species, Colonial Waterbirds/Seabird Concentrations, Nationally Significant: Threatened Species, Congregatory Species
Conservation status: IBA Conservation Plan written/being written, Provincial Park (including Marine)
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Site Description

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.


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.

Summary of bird records available for Scott Island Group
Click here to view all records
Species Season Number Unit Date
Black Oystercatcher BR 29 N P 1989
Brandt’s Cormorant BR 39 N P 1989
Cassin’s Auklet BR 990,000 G P 1989
Colonial Waterbirds/Seabirds BR 2,177,216 G I 1989
Colonial Waterbirds/Seabirds BR 1,090,000 G P 1989
Common Murre (Pacific) BR 4,100 N P 1989
Fork-tailed Storm-Petrel BR 3,000 N P 1989
Glaucous-winged Gull BR 1,077 N P 1989
Horned Puffin BR 11 P 1989
Leach’s Storm-Petrel (E. Pacific) BR 12,700 G P 1989
Pelagic Cormorant BR 33 – 607 N P 1982 – 1989
Peregrine Falcon (pealei) BR 2 N P 1989
Pigeon Guillemot BR 619 N I 1989
Rhinoceros Auklet BR 41,700 G P 1989
Thick-billed Murre (Pacific) BR 7 P 1989
Tufted Puffin BR 34,900 G P 1989
Note: species shown in bold indicate that their population level (as estimated by the maximum number) exceeds at least one of the IBA thresholds (national, continental or global). The site may still not qualify for that level of IBA if the maximum number reflects an exceptional or historical occurence.
Conservation Issues

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.

Scott Islands IBA