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Sidney Channel (BC047)


Sidney Channel (BC047)

Saanich Peninsula, British Columbia

Latitude 48.626°N
Longitude 123.358°W
Altitude 0m
Area 87.10km²

Site Description

Sidney Channel is a 4 km wide body of water that lies along the extreme southeast shore of Vancouver Island between James Island (and the larger Saanich Peninsula) and Sidney Island. Along with Haro Strait, it connects the Juan de Fuca and Georgia Straits. Both Sidney and James Island are overlain by unconsolidated glacio-marine and outwast sand deposits. Large schools of a smelt, known as sandlance, reproduce in the sand, and subsequently attract large flocks of seabirds in spring and summer. The eroded sand has also formed a lagoon at the northwestern end of Sidney Island, which attracts hundreds of sandpipers in the spring and summer.


Sidney Channel is noted for the variety of marine birds that occur at the site throughout the year. Although most places along the south coast of the Strait of Georgia have relatively few birds in summer, the channel and lagoon on Sidney Island are well known for the presence of murrelets, auklets, cormorants, gulls and shorebirds. During winter, seaducks are spread throughout the channel, and during the spring they are joined by migrating grebes, loons, brant, and shorebirds.

Of particular significance at this site are the large concentrations of Brandt's Cormorants during fall migration (just over 1% of the worlds estimated population), and Mew Gulls and Brant during spring migration (about 1% of the northeastern Pacific Mew Gull population, and 1-2% of estimated Pacific Brant population). During fall, winter, and spring, large number of Pigeon Guillemots are also present (almost 3% of the estimated national population) and about 300 Brant over-wintered in 1996-1997. In addition, about 20 pairs of nesting Black Oystercatchers (about 2% of the estimated national population) nest on islets located in the area.

About 50 Marbled Murrelets (listed as nationally threatened) are also regularly reported at this site. Although breeding sites for these birds have not been found, these observations may represent a remnant local breeding population. (Many of the southern Georgia Strait breeding populations have been extirpated as result of the cutting of old growth forest). In addition to the Marbled Murrelets, about 50 Great Blue Herons (ssp. fannini nationally vulnerable) are also regularly recorded feeding at this site. In 1988, 100 pairs were reported to nest on Sidney Island, but since then the colony has been abandoned.

Conservation Issues

Sidney Channel is located in an area that is affected by a multitude of land uses. For example: sewage from towns on the Saanich Peninsula is deposited into the channel; tanker traffic to and from a large ARCO oil refinery at Cherry Point, Washington passes about 5 km to the north and east along Haro Strait; a crab fishery operates in the strait; thousands of recreational boaters from marinas in both the U.S. and Canada utilize the channel (Sidney is the first Canadian Customs Point); and sea-kayakers travel along the shore. The northern end of Sidney Island including Sidney Spit became part of the Gulf Islands National Park Reserve in 2003. It was formerly the Sidney Spit Marine Park under provincial jurisdiction. The park area comprises about 400 acres at the north end of the island. The southern end of Sidney Island, and all of James Island, is privately owned.

IBA Criteria Habitats Land Uses Potential or Ongoing Threats Conservation Status
Marbled Murrelet
Number Year Season
Heermann's Gull
Number Year Season
60 - 672017Fall
24 - 1002016Fall
25 - 502016Summer
40 - 452015Fall
67 - 1052015Summer
65 - 752014Fall
24 - 1802009Summer
30 - 902007Summer
Great Blue Heron
Number Year Season
Yellow-breasted Chat
Number Year Season
Pelagic Cormorant
Number Year Season
Number Year Season
Iceland Gull (Thayer's)
Number Year Season
Red-necked Grebe
Number Year Season