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Location Canada, Nunavut
Central coordinates 100o 19.84' West  65o 55.27' North
IBA criteria A4iii
Area 160,000 ha
Year of IBA assessment 2008

Bird Studies Canada/Nature Canada

Site description 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.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
A4iii Species group - waterbirds passage  1986  20,000-49,999 individuals  unknown  A4iii   

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Thelon Wildlife Sanctuary Wildlife Sanctuary 5,579,634 protected area overlaps with site 4,000  


IUCN habitat Habitat detail Extent (% of site)
Grassland Edaphic grassland  -
Wetlands (inland) Freshwater marshes/swamps; Rivers  -

Land use

Land-use Extent (% of site)
not utilised major

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Middle Back River. Downloaded from on 26/10/2016

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