ANCHORAGE, Alaska (AP) – Hundreds of Pacific walruses came ashore to a barrier island on Alaska’s northwest coast, the earliest appearance of the animals in a phenomenon tied to climate warming and diminished Arctic Ocean sea ice.

The U.S. Fish and Wildlife Service announced Wednesday that several hundred walruses were spotted during the first week of August near the village of Point Lay on the Chukchi Sea. Last week, the number had grown to 2,000, said spokeswoman Andrea Medeiros in an email response to questions.

It’s the earliest date for the arrival, known as a “haulout,” to...