Melting Arctic sea ice drives walruses onto land
Fast-melting Arctic sea ice appears to be pushing walruses to haul themselves out onto land, and many are moving around the area where oil leases have been sold, the U.S. Geological Survey reports.
Walruses are accomplished divers and frequently plunge hundreds of feet (meters) to the bottom of the continental shelf to feed. But they use sea ice as platforms to give birth, nurse their young and elude predators, and when sea ice is scarce or non-existent, as it has been this summer, they come up on land.
Last September, the loss of sea ice caused an estimated 10,000 to 20,000 walruses to venture onto land, and as sea ice melts reached a record last month, U.S. government scientists are working with Alaskan villagers to put radio transmitters on some of the hauled-out walruses to track their movements around the Chukchi Sea.
"The ice is very widely dispersed and there is little of it left over the continental shelf," researcher Chad Jay of the U.S. Geological Survey said in a statement on Wednesday. "Based on our tracking data, the walruses appear to be spreading out and spending quite a bit of time looking for sea ice."
The loss of sea ice puts Pacific walruses at risk, according to the U.S. Fish and Wildlife Service, but other, higher-priority species will get attention first. In February, the wildlife service listed Pacific walruses as candidates for protection, though not protection itself.
Walruses are protected under the Marine Mammal Protection Act, which means these animals cannot be harvested, imported, exported or be part of interstate commerce.
Polar bears, which also use sea ice in the Chukchi Sea as platforms for hunting, have been designated as threatened under the U.S. Endangered Species Act because of declining sea ice in the Arctic.
Compared to last year's massive haul-out, there are few walruses on land, and there is no solid count, Jay said.
"There is a lot less ice than there used to be on the continental shelf this time of year," he said. "So we might be headed into a new normal."
Photo shows Walrus on Bering Sea Ice
Photo Credit: Liz Labunski/USFWS