Middle Back River

Country/territory: Canada

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

Area: 160,000 ha

Birds Canada / Nature Canada

Site description (baseline)
This site follows the middle part of the Back River, in southern Nunavut, where it widens to include Pelly, Upper Garry, Garry, and Lower Garry lakes (the latter to 99°W). The area has low relief and the substrates are glacial silts, sands and gravels. Meadows of sedges and grasses are located along the shores of the lakes and rivers. This river is isolated with no nearby communities.

Key biodiversity
In late summer the middle section of the Back River supports many moulting Canada Geese. In 1986, 32,300 geese were recorded, and the two-year average (1984 and 1986) was 21,050 geese. These Canada Geese may be subspecies maxima (Mississippi Flyway Giants) or moffitti (Western Prairie/Great Plains, Hi-line and Rocky Mountain populations) or they may be from the Tall Grass Prairie population. Although the exact Canada Goose population is unknown, this site most likely supports more than 1% of whichever population is present. The moulting geese arrive in mid-June and leave in mid or late August. They feed in the shoreline grass-sedge habitats and roost and loaf in areas of open water.

In summer, Snow Geese breed in the Pelly Lake area. Between 1984 and 1988, an average of 5,065 Lesser Snow Geese (Western Canadian Arctic population) bred in the area with a peak of 9,000 in 1987. There are two reasons for the annual variation in numbers of breeding Snow Geese. First, the Lesser Snow Goose population has increased rapidly over the last several decades. Second, in years of late snow melt, Snow Geese en route to the more northerly Queen Maud Gulf colonies may short-stop to breed and this site.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Middle Back River. Downloaded from on 31/05/2023.