email a friend
printable version
Location Canada, Nunavut
Central coordinates 79o 29.98' West  72o 55.27' North
IBA criteria A1, A4i, A4ii, A4iii
Area 200,000 ha
Altitude 0 - 500m
Year of IBA assessment 2008

Bird Studies Canada/Nature Canada

Site description Bylot Island is located at the south-eastern corner of the Lancaster Sound along the northern edge of Baffin Island. Navy Board Inlet, Eclipse Sound, and Pond Inlet separate Bylot Island from the much larger Baffin Island to the south and west. Much of Bylot Island is characterized by glaciers and mountains that rise to an elevation of 1900 metres above sea level. A rolling outwash plain occurs on the southwest corner of the island, directly north of Eclipse Sound. Glacial rivers have dissected the plain, which rises about 60 metres above sea level and slopes gradually upwards to the mountains. The vegetation on the plain is dominated by low shrub-herb, and shrub-sedge tundra. In the river valleys, heath, willow, and other flowering plants are more common.

Key Biodiversity The southwest plain of Bylot Island contains the largest known breeding colony of the Greater Snow Goose (ssp. atlanticus). Nesting colonies of a few pairs to several thousand geese are scattered over the entire plain. Like other populations of white geese in the Canadian Arctic, the Greater Snow Goose population has risen dramatically since the mid 1960s (about 11% annually). The population on South Bylot has experienced similar growth, with 15,100 breeders being recorded in 1983, 26,700 breeders in 1988, and 55,000 breeders in 1993. In all, the 1993 population (including non-breeders and juveniles) was 156,000 birds. The breeders and non-breeders represent about 16% of the estimated 1993 spring population of this subspecies. In 1988, the number of breeding geese on Southwest Bylot represented about 13% of the Greater Snow Goose population.

The southwest Bylot Island breeding bird community has been well studied. Between 1992 and 1997, 31 breeding species were recorded in study plots within the plain. Overall, the most common species were Lapland Longspur, Snow Goose, American Golden Plover, Baird's Sandpiper, and Long-tailed Jaeger. Other species present in relatively larger numbers were Snow Bunting, Horned Lark, American Pipit, and Snowy Owl, the owls only being present during years when lemming numbers were high. The number of species and density of nesting pairs at this site is greater than at all other sites in the Canadian Arctic Archipelago north of 70° latitude where detailed avifaunal surveys have been completed. All of the species identified as being largely restricted to the Arctic Cordillera Biome occur as nesters on the southwest plain, with the exception of Ivory Gull.

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Snow Goose Anser caerulescens non-breeding  1993  156,000 individuals  A4i  Least Concern 
Ivory Gull Pagophila eburnea non-breeding  1994  75 individuals  A1, A4i  Near Threatened 
Thick-billed Murre Uria lomvia breeding  1975  420,000 breeding pairs  A4ii  Least Concern 
A4iii Species group - seabirds breeding  1975  100,000-499,999 breeding pairs  unknown  A4iii   

Protected areas

Protected area Designation Area (ha) Relationship with IBA Overlap with IBA (ha)  
Bylot Island Migratory Bird Sanctuary 1,263,500 protected area overlaps with site 140,000  
Sirmilik National Park 2,210,732 protected area overlaps with site 110,000  


IUCN habitat Habitat detail Extent (% of site)
Grassland Tundra  -
Coastline Rocky flats & barrens  -

Land use

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

Contribute  Please click here to help BirdLife conserve the world's birds - your data for this IBA and others are vital for helping protect the environment.

Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Southwest Bylot. Downloaded from on 28/10/2016

To provide new information to update this factsheet or to correct any errors, please email BirdLife