Mysteriously, 25 Pacific walrus were found dead on an isolated beach in northwest Alaska. Among the dead were 12 pups. Many were missing their heads and tusks. The US Fish and Wildlife Service have announced an investigation.

“We can’t come to any conclusions based on a report,” said Andrea Medeiros, spokeswoman for the agency. “You have to go out and investigate.”

Federal law stipulates that only Alaskan Natives may hunt walrus for subsistence or for the creation of traditional items. However, anyone is allowed to collect bones, teeth, and ivory from marine animals found dead on land a quarter mile away from the ocean.

Walrus skulls, with tusks attached, are valuable collectors’ items; the tusks’ ivory is also valuable. Walrus killed exclusively to gather skulls and tusks is considered immoral and highly illegal.

The dead animals were spotted by an Air Force radar station operative at Cape Lisburne. The carcasses were photographed and the US Fish and Wildlife Service notified.

Investigators rushed to the scene as quickly as possible in order to thoroughly examine the bodies before other animals, such as polar bears or sea gulls, started to eat them.

“Time is of the essence,” said Medeiros. “We really appreciate people notifying us promptly.”

The investigation needs to determine if the animals died naturally in the ocean, then washed ashore. Or if there was foul play involved.

As global warming diminishes the amount of summer sea ice, walrus are growing increasingly threatened. In 2014, the Artic sea ice was 240,000 square miles less than the previous year. It currently stands at a mere 1.7 million square miles, the fourth-lowest level ever recorded.

Females with pups ride the edge of the sea ice north towards the Bering Strait. They use the floating ice as a mobile platform from which to dive as well as to rest. Small pups cannot swim far distances without getting exhausted.

Climate change has caused the sea ice to recede further and further north. At this point, the ice is floating two miles above the shallow continental shelf. This is a problem as walrus mainly eat clams, snails, and urchins found on the ocean floor. An adult walrus cannot swim two miles beneath the surface, let alone a young pup.