While surveying walruses on a mile stretch of beach near the Inupiaq Eskimo village of Point Lay in Alaska, officials from the U.S. Fish and Wildlife Service (USFWS) discovered the bodies of 64 young walruses among the thousands of other walruses that have migrated to the area over the past month.
Though the cause of the deaths is unknown, experts suspect they died in a stampede, the USFWS told the Associated Press.
"Our thinking is, because of the age of the animals—they were young animals—it's likely that it was caused by a stampede, probably more likely than disease, given the age class," USFWS spokeswoman Andrea Medeiros told the AP.
All the dead walruses were under a year old.
Walruses make a mad dash en masse into the ocean when they become startled, usually by a polar bear, hunter, airplane or boat. As the larger walruses rush to the sea, they crush the smaller animals, which are vulnerable when side by side with females weighing a ton apiece.
Alaska Native residents in Point Lay pointed to an airplane seen flying near the herd and possibly circling as the potential reason for the stampede.
Single-engine airplanes are supposed to remain a half-mile away or be at least 2,000 feet above so as not to disturb the walruses. Helicopters and multi-engine aircraft are to remain a mile away or 3,000 feet above them.
"That certainly is a concern," Medeiros told the AP about the plane sighting. "That's not what we want people to be doing."
The USFWS said disturbing the walruses is a violation of federal law.
More about the walruses from the Associated Press:
Several hundred walruses came ashore near Point Lay on Aug. 3, the earliest recorded appearance of a herd in a phenomenon tied to climate warming and diminished Arctic Ocean sea ice.
A week later, the number had grown to 2,000. In the past month, 30,000 to 40,000 walruses at times have crowded the beach, Medeiros said.
Walrus dive hundreds of feet to eat clams on the ocean bottom, but unlike seals, they cannot swim indefinitely. Historically, sea ice has provided a platform for rest and safety far from predators for mothers and calves north of the Bering Strait.
However, sea ice has receded much farther north in recent years because of global warming, beyond the shallow continental shelf, over water more than 10,000 feet (3,050 meters) deep. That’s far too deep for walruses to reach the ocean bottom.
Instead of staying on sea ice over the deep water, walruses have gathered on shore to rest.
Read more about walruses on GrindTV