The Koktac River Archipelago stretches for about 70 km along the northeastern Hudson Bay coastline. There are 768 islands in the group, with two islands larger than 500 ha and most islands less than 50 ha in size. Although the islands lie very close to the Quebec mainland they are in fact in Nunavut territory. The community of Inukjuak is located just to the north of this site and Povungnitak is located to the south. The Koktac River flows westward to meet the sea in the southern portion of the archipelago.
In 1985, about 2,300 pairs of nesting Common Eider (ssp. sedentaria) were recorded on these islands. At that time, this represented about 9.4% of the estimated population for the sedentaria subspecies that breeds and winters in Hudson and James Bay. However, the population of this subspecies is thought to have declined dramatically since then with some of the larger colonies experiencing as much as a 75% decline. A particularly cold winter in 1991-92 caused many of the traditional wintering areas (polynyas and ice-flow edges) to freeze over. A recent survey of the colony on the Koktac River Archipelago has not been completed to determine whether a similar decline has occurred.
Most of the nests recorded in 1985 were found on only 15% of the islands. These islands were not concentrated in any one area, but were scattered throughout the archipelago. About 10% of the nests were on the islands in the foreshore flats.
Many Common Eider colonies are in isolated locations where few birds nest. However, at the Koktac River Archipelgo about 160 Glaucous Gulls and Herring Gulls nest on the same islands as the eiders. Also, a large number Arctic Terns (870 pairs) nested there in 1985.
BirdLife International (2022) Important Bird Areas factsheet: Koktac River Archipelago. Downloaded from http://www.birdlife.org on 18/08/2022.