ANCHORAGE, Alaska — Pacific walrus have come ashore on the northwest coast of Alaska in what has become an annual sign of the effects of climate change.

“There appears to be several thousand animals up there,” said Andrea Medeiros, spokeswoman for the U.S. Fish and Wildlife Service in Anchorage.

Images of the walrus were captured over the weekend by a photographer not affiliated with the agency near Point Lay, an Inupiat Eskimo village 700 miles northwest of Anchorage and 300 miles southwest of Barrow.

Walrus have been coming to shore on the U.S. side of the Chukchi Sea in large numbers for about eight years. They also come to shore on the Russian side.

Researchers say it’s likely a result of less sea ice brought on by climate warming.

Walrus dive to feed on clams, sea snails and other food on the ocean bottom but cannot swim indefinitely.

Many male walrus never leave the Bering Sea but females, especially mothers with pups, ride the edge of the sea ice as it moves north in summer through the Bering Strait and into the Arctic Ocean. They use sea ice as a platform from which to dive for food while pups rest on the ice.

In recent years, sea ice has receded north beyond shallow continental shelf waters and over water that exceeds 2 miles deep, beyond the diving range of an adult walrus.

Walrus in large numbers were first spotted on the U.S. side of the Chukchi Sea in 2007. They returned in 2009, and in 2011, scientists estimated 30,000 walruses along 1 kilometer of beach near Point Lay.

Last year, an estimated 35,000 walrus were photographed 5 miles north of Point Lay.

The agency and two others last week issued an appeal to stay away from large gatherings of walrus that come ashore. Young animals are vulnerable to stampedes when a group gathers nearly shoulder-to-shoulder on a beach.

Stampedes can be triggered by a polar bear, human or low-flying airplane.

The carcasses of more than 130 mostly young walruses were counted after a stampede in September 2009 at Alaska’s Icy Cape.

With this year’s low summer sea ice, it’s not surprising to see walrus on shore looking for a place to rest, Margaret Williams of the World Wildlife Fund in Anchorage said in a statement. The sharp decline of Arctic sea ice over the last decade is leading to major changes for wildlife and communities.

“Such extreme events are a stark reminder of the urgent need to ratchet down the emissions that are warming our planet,” Williams said.