Akimiski Strait

Country/territory: Canada

IBA criteria met: A4i, A4iii (2008)
For more information about IBA criteria, please click here

Area: 91,000 ha

Birds Canada / Nature Canada

Site description (baseline)
Akimiski Strait is located in James Bay between the Ontario mainland and Akimiski Island. It is approximately 15 to 20 km wide and stretches from Ekwan Point in the north to the mouth of the Kapiskau River in the south. Within the strait, the water is relatively shallow and there are numerous submerged shoals and small gravelly islands mostly concentrated from the western tip of Akimiski northward. The largest islands have some deciduous scrub and stunted trees, while vegetation on the smaller islands is restricted to sparse grasses and other herbaceous plants. Supertidal coastal marshes extend inland along the Ontario shore for a km or more. The main freshwater discharge is the Attawapiskat River, which is located approximately near the centre of this strait. At this location, intertidal marshes and shoals extending offshore for at least 5 km. During the winter, a polynya (an ice-free area caused by currents and upwellings) is located within the strait.

Key biodiversity
The Akimiski Strait supports tremendous numbers of staging waterfowl during both the spring and fall migration. The most numerous species is the Snow Goose, with one-day estimates from the late 1970s being as high as 68,000 during spring migration. During the fall, one-day counts have been as high as 15,000. No systematic surveys have recently been completed at this site, but casual observations suggest that large numbers still use the area.

In addition to Snow Geese, large numbers of Brant, and Canada Geese also utilize this area during spring and fall migration respectively. In May 1994, a one-day count of 8,700 Brant was recorded, which represents about 7% of the estimated eastern (ssp. hrota) population. Canada Geese numbers (from the tall grass prairie population ssp. hutchinsii) have been as high as 9,000 during a one-day count in 1982. This would represent from 5 to 10% of the estimated population. It is likely that large numbers of both these species also use this site during spring migration, but few surveys have been completed to document numbers. Clearly, the open water leads from freshwater discharge and strong currents provide important early spring staging habitat for many species. Not only is the site an important staging area: it also acts as a major bottleneck for all of the birds that migrate along the coast of James Bay.

A large colony of Caspian Terns is located the gravelly islands in the strait. At least 100 pairs were present in the early 1980s, and even though the colony had moved to other islands in 1995 a similar number were estimated that year too. There is likely about 1% of the species national population present. Ring-billed Gulls and Herring Gulls also nest here. Yellow Rails (nationally vulnerable) are also reported to be common in the coastal marshes, although no population estimates are available.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Akimiski Strait. Downloaded from on 31/05/2023.