America and Russia work together during challenging times
20 April 2021
Studying polar bears is not easy, even in ideal conditions. The Arctic is immense and remote in a way that is hard to fathom in our world of fast travel and instant communication. Research is expensive, often dangerous and takes months of planning. Eric Regehr explains how, like so many other things, research became even more difficult with COVID-19—and how teamwork kept it going.
Although 2020 saw most field research projects cancelled across the Arctic, not all the news was bad. The Chukchi Sea polar bear subpopulation was a welcome bright spot, not only in terms of how the bears are faring, but because of a unique collaboration that allowed research to continue even as the pandemic ground most activities around the world to a halt.
The Chukchi Sea polar bear subpopulation inhabits the ice of the Bering, Chukchi and East Siberian seas, with bears moving freely between the United States and Russia. In 2008, when polar bears were listed as threatened under the Endangered Species Act, the American government started live-capture research on the subpopulation that involved immobilizing bears on the sea ice. That study provided a wealth of information on the habitat use and nutritional ecology of these bears, not to mention the first proper estimate of their abundance: it turns out there are about 3,000 bears, one of the world’s largest subpopulations.
Intriguingly, from 2008 to 2017, researchers found that Chukchi Sea polar bears maintained good body condition (fatness) and reproduction rates despite climate change, likely due to the region’s high biological productivity. Although sea-ice loss has not yet had negative effects on these bears, it has, ironically, limited scientists’ ability to study them. In the past decade, large areas of spring ice west of Alaska have transitioned from a solid platform capable of supporting a helicopter to an unstable surface that even polar bears are reluctant to cross. With the ice literally melting beneath our feet, it was clear that we needed a new approach to continue studying this subpopulation.
Wrangel Island: A sanctuary
Enter Wrangel Island, a 7,600-square-kilometre island with the greatest level of environmental protection in Russia. Each summer when the ice melts, most Chukchi Sea bears come to Wrangel to rest until the ocean freezes again. Pregnant females give birth in snow dens on the island, emerging with new cubs in the spring. In 2016, American and Russian scientists began collaborative research on Wrangel under a bilateral treaty. By 2019, they had collected data on habitat use, body condition and reproduction for 1,600 polar bears. They used non-invasive methods to collect genetic samples from another 100.
In addition to collecting data needed for management and conservation using systematic survey methods, the project has sought to build capacity among Russian scientists. This paid dividends in 2020 when experienced staff from the Wrangel Island State Nature Reserve conducted research without American participation (due to COVID-19 restrictions). The researchers collected observational data on a record 747 bears and genetic samples from 113 bears.
Climate change is the primary threat to polar bears. Even subpopulations like the Chukchi Sea, which appear to be doing well for now, are expected to experience stress and declining numbers as sea-ice loss continues. As the summers lengthen, Wrangel Island is providing bears with a critical terrestrial refuge and researchers with an opportunity to collect data needed for managing and conserving the Chukchi Sea subpopulation. American-Russian research on the island represents the type of international cooperation and capacity development that will be increasingly important as climate change affects both polar bears and our ability to study them.
This study is supported by the Wrangel Island State Nature Reserve, the University of Washington, the US Fish and Wildlife Service, WWF, the All-Russian Research Institute for Environment Protection, Polar Bears International, the Alaska Department of Fish and Game and the Campion Foundation.
ERIC REGEHR is principal quantitative ecologist with the Polar Science Center at the University of Washington and principal investigator on American–Russian polar bear research on Wrangel Island. He has worked with 11 of the world’s 19 polar bear subpopulations.
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