Federal prosecutors have opened a criminal investigation into the deaths of 25 Pacific walrus found last week on an isolated northwest Alaska beach.
The U.S. Fish and Wildlife Service on Wednesday received a report and photos of the dead animals found near Cape Lisburne on the Chukchi Sea about 230 miles northeast of the Bering Strait.
Initial reports indicated the walrus — 12 pups and 13 adults — had been shot. However, the agency would not speculate on the causes of death and sent two officers from its law enforcement division to investigate.
The officers have not returned, said USFWS spokeswoman Crystal Leonetti on Monday. She said she could not reveal details of what they found. Additional information will only be released by the U.S. Attorney's office.
"We've opened an investigation and can no longer answer questions about it," she said.
The dead walrus were reported by a person connected to an Air Force radar station at Cape Lisburne.
Some walrus were missing heads and tusks. Walrus ivory is prized for jewelry and crafts. Skulls with tusks attached are collectors' items.
Only Alaska Natives who live in the state may hunt walrus. Walrus killed solely for ivory with the meat wasted is illegal.
The fate of walrus has become a cause for concern as climate warming diminishes summer sea ice. Arctic sea ice hit its summer minimum this month 1.7 million square miles, down 240,000 square miles from 2014, according to the National Snow and Ice Data Center. It's the fourth-lowest level on record for minimum summer sea ice.
Walrus breed in the Bering Sea. Many walrus found in the Chukchi Sea north of the Bering Strait are females with pups that use ice as a platform from which to dive and rest. As ice melts, walrus move north over new feeding areas.
The animals eat clams, sea snails and other food on the ocean bottom but cannot swim indefinitely. In recent years, sea ice has receded north beyond the shallow continental shelf to water that exceeds 2 miles deep, beyond the diving range of an adult walrus.
Walrus in large numbers on shore were first spotted on the U.S. side of the Chukchi Sea in 2007. An estimated 35,000 Pacific walrus were photographed Sept. 2 near Point Lay about 100 miles northeast of Cape Lisburne.
When in massive herds, walrus can stampede and trample their young if startled by an airplane, hunter or polar bear.
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