Site Complet

Lancaster Sound Polynya (NU058)


Lancaster Sound Polynya (NU058)

Nanisivik, Nunavut

Latitude 74,160°N
Longitude 79,605°O
Altitude 0m
Superficie 8 727,65km²

Description du site

The Lancaster Sound Polynya is located between the northwestern end of Baffin Island and the south coast of Devon Island. The shape and extensiveness of the polynya (an area of open water surrounded by ice, varies from year to year) and associated leads is influenced by the severity of the winter, water currents and winds. Landfast ice starts to develop in late September, with the sound becoming completely ice-covered by mid to late October. Leads and cracks begin to form between mid November and mid December, and remain until break-up. One of the most regularly occurring leads is one that develops along the south coast of Devon Island. In the 1970s break-up occurred any time between early May and August. Many large marine mammals, such as Bearded Seals, Belugas, Walruses and Polar Bears, feed in the waters here.


The Lancaster Sound Polynya supports an amazing number of migrant Dovekies. During the latter half of May, this small alcid is migrating north to its breeding grounds in the Thule District of northwest Greenland, where many millions of Dovekies breed. On route, they stop at the Lancaster Sound Polynya to feed along the ice edges and loose drift ice of the open water found here.

In the latter half of May, 1976, aerial surveys of the eastern end of Lancaster Sound led to estimates of 1.5 million Dovekies. During the same time of the year in 1978, aerial surveys of an adjacent area in the sound led to estimates of 6 million and 14 million Dovekies. This is a significant portion of the Thule breeding population and an outstanding number by any measure.

Enjeux de conservation

Even the infrequent ship traffic and oil exploration in these northern waters could result in oil spills, potentially leading to high bird mortality. Due to the remoteness of Lancaster Sound, there are currently no other concerns for the birds in this location.

Catégories ZICO Habitats Usages Menaces Potencielles ou Existantes Status de Protection
Mergule nain
Nombre Année Saison
6 000 000 - 14 000 0001978Printemps
71 012 - 1 500 0001976Printemps