This recurring nearshore polynya lies ai the 66-98 foot (20-30 m) isobath south of the Chukotsky Peninsula between Meechkin Spit and Cape Chukotsky. It extends 37-43 miles (59-69 km) from shore and in warmer winters may connect with the St Lawrence island polynya to the southeast. The polynya is formed by a combination of prevailing offshore north-winds and strong coastal currents.
This extensive polynya constitutes one of the most northern wintering habitats for eiders (including the threatened Steller’s eider) and long-tailed ducks, along with lesser numbers of pelagic cormorants, glaucous gulls, ivory gulls, Ross’s gulls, thick-billed murres, black guillemots and Kittlitz’s murrelets. Its open waters in a vast sea of ice are believed primarily responsible for the existence of the most northerly northern fulmar colonies in the Pacific. These waters are also important during spring migration for snow geese, emperor geese, brant, eiders and long-tailed ducks, and provide summer feeding grounds for the 1.5 million seabirds of 13 species that nest in colonies along the adjacent coast.
Other notable wildlife: Several hundred Pacific walrus are believed to breed in and around the polynya. Bowhead and gray whales feed there along with pods of beluga whales and seals. Polar bears are attracted to its ice edges in search of seals.
BirdLife International (2019) Important Bird Areas factsheet: Sireniki shore of Chukotka. Downloaded from http://www.birdlife.org on 21/04/2019.