Current view: Text account
Site description (2004 baseline):
Site location and context
At 18.6 square miles (48 sq km), this is the largest of the Diomede Islands located near the corner of the 53-mile-wide (85 km) Bering Strait 26 miles (42 km) east of Cape Dezhnev (65°46'N; 169°03'W). The entire island is designated a Russian border guard outpost and is closed to public access.
The estimated two million crested auklets and one million least auklets make Big Diomede one of the largest colonies for these two species in the North Pacific. There also are substantial numbers of nine other species of nesting seabirds: black-legged kittiwakes, common and thick-billed murres, parakeet auklets, pigeon guillemots, pelagic cormorants, and homed and tufted puffins. Other birds commonly sighted include western sandpipers, rufous-necked stints, Baird’s sandpipers, yellow wagtails, red-throated pipits, northern ravens, common redpolls, snow buntings and Lapland longspurs.
Other notable wildlife: A large walrus haul-out is located on the island’s southwestern shore. Bering Strait is a major migration corridor between the Bering and Chukchi seas for bowhead, gray and beluga whales, Pacific walrus, polar bears and seals.
Sea cliffs, alternating with scree slopes and bedrock, predominate on the northern and southern portions of the 14-mile (22 km) coastline. Northward flowing currents through Bering Strait concentrate zooplankton a short distance north of the island.
Pressure/threats to key biodiversity
There is the danger of future oil spills and disturbance from vessel traffic along the Northern Shipping Route. Disruption of marine food chains and incidental take of seabirds in fishing gear would accompany expansion of commercial fishing into island waters.
Conservation responses/actions for key biodiversity
No oil and gas development should be permitted in Bering Strait Access to the island is needed for Russian biologists to conduct periodic seabird monitoring. The island appears an ideal unit for inclusion in the proposed Beringian Heritage International Park.
The map polygon is provided courtesy of the Spatial Database on Important Bird Areas of Russia 2014 (© Russian Bird Conservation Union, © Transparent World).
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Ratmanova Island (Russia (Asian)). Downloaded from
https://datazone.birdlife.org/site/factsheet/ratmanova-island-iba-russia-(asian) on 22/11/2024.
