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ANCHORAGE, Alaska (AP) – The first formal count of polar bears in the United States and Russia indicates they are doing better than some of their cousins elsewhere.
Polar bears are listed as a threat because of climate change. But university and federal researchers estimate a robust and abundant population of nearly 3,000 animals in the Chukchi Sea off Alaska's northwest coast, according to a study published Wednesday in Scientific Reports.
Eric Regehr, lead author of the United States of America, has recently started a research project at the University of Washington's Polar Science Center.
In the longer term, it does not mean the Chukchi Sea bear population will not be affected.
"Reinsurer," Regehr said, "Polar bears need ice to hunt seals, and the ice is projected to decline.
The study shows there is variation around the world in the effects of sea ice, he said Thursday.
"Some subpopulations are still declining while others are still doing OK," he said.
Polar bears are classified as mammals because they spend most of their lives on sea ice. Less sea ice means less productive, more time on shore and longer, energy-sapping swims.
The world's polar bears are divided into 19 subpopulations, including two in U.S. waters. Besides Chukchi bears, the United States shares the southern Beaufort Sea population with Canada.
Stress in southern United States in the United States of America.
Fewer cubs were surviving on their second year and adult males weighed less and had smaller skulls, the U.S. Geological Survey found. Steven Amstrup, Researcher at the time said the trends have been made in the US.
A more recent study by USGS research Karyn Rode found that Chukchi bears spend more time on shore and has almost 30 fewer days to hunt seals on ice than 20 years ago, Regehr said. However, that does not appear to have affected the population, he said.
Polar bears have an amazing ability to build fat reserves, Regehr said, and the Chukchi 's abundant seal population can be used to compensate for the loss of hunting time. The difference with the southern Beaufort was obvious from an airplane, he said.
"It's visually striking to me, the difference, having worked in both places," Regehr said.
When ice melts, many Chukchi bears rest on Russia's Wrangell Island, where they occasionally find a whale or walrus carcass.
The Chukchi population study used data collected by sampler about 60 polar bears between 2008 and 2016. Some were fitted with GPS transmitters. The data was used in a model designed to estimate population size for highly mobile large carnivores.
Blaine Griffen, an associate professor of biology at Brigham Young University, said the study was good news.
"It's nice to see that there's more people doing it better than others," he said.
The difference may be geography, he said. The Chukchi Sea has a more extensive shelf with primary productivity that allows the food chain to support seals.
Chukchi bears would do better than bears elsewhere, Griffen said.
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