By SETH BORENSTEIN, AP Science Author
With the polar bear species in a struggle for survival due to disappearing Arctic sea ice, a brand new distinct group of Greenland bears appear to have came across an icy oasis which may permit a small distant inhabitants to “grasp on.”
Nevertheless it’s removed from “a life raft” for the endangered species that has lengthy been an emblem of local weather change, scientists mentioned.
A staff of scientists tracked a gaggle of some hundred polar bears in Southeast Greenland that they present are genetically distinct and geographically separate from others, one thing not thought-about earlier than. However what’s actually distinct is that these bears handle to outlive regardless of solely having 100 days a 12 months when there’s sea ice to hunt seals from. Elsewhere on the earth, polar bears want at the least 180 days, often extra, of sea ice for them to make use of as their looking base. When there’s no sea ice bears usually don’t eat for months.
With restricted sea ice, which is frozen ocean water, these Southeast Greenland polar bears use freshwater icebergs spawned from the shrinking Greenland ice sheet as makeshift looking grounds, in line with a examine in Thursday’s journal Science. Nevertheless, scientists aren’t positive if they’re thriving as a result of they’re smaller and have fewer cubs than different polar bear populations.
“These polar bears are tailored to dwelling in an surroundings that appears like the longer term,” mentioned examine lead creator Kristin Laidre, a polar bear biologist on the College of Washington, who over 9 years tracked, collared and examined the all-white bears often from a helicopter hovering the white snow and ice backdrop. “However most bears within the Arctic don’t have glacial ice. They don’t have entry to this. So it will possibly’t be taken out of context like one way or the other this is sort of a life raft for polar bears across the Arctic. It’s not. Greenland is exclusive.”
“We mission giant declines of polar bears throughout the Arctic and this examine doesn’t change that essential message,” Laidre mentioned. “What this examine does is present that we discover this remoted group dwelling on this distinctive place… We’re the place within the Arctic polar bears can as a species grasp on, the place they may persist.”
The freshwater ice will preserve coming off the ice sheet for hundreds of years giving restricted hope that that is “a spot that polar bears may proceed to outlive’’ but it surely’s separate from an general development of sea ice loss in the summertime due to emissions of heat-trapping gases from the burning of coal, oil and pure fuel, mentioned Nationwide Snow and Ice Knowledge Middle deputy lead scientist Twila Moon, a examine co-author.
These bears hunt on the recent glacial ice that has extra peaks and valleys than the flatter sea ice, usually in house- or car-sized bergs, known as bergy bits, Moon mentioned.
This inhabitants of polar bears are on the southeast tip of the enormous island, the place there aren’t any cities. For years scientists figured these bears had been a part of the identical inhabitants in Northeast Greenland, simply roaming up and down the large coast. However they don’t, Laidre mentioned. An uncommon arrange of winds, currents and geographical options round 64 levels North make it subsequent to not possible for bears to maneuver north of that time, the present sends them south quick, she mentioned.
Whereas most bears journey 25 miles (40 kilometers) over 4 days, the Southeast Greenland bears go about 6 miles (10 kilometers) in the identical time, the examine mentioned.
“They simply keep in the identical place for years and years,” Laidre mentioned.
Genetic testing Laidre and colleagues did confirmed they’re extra completely different from the neighboring populations than another pair of polar bear populations on Earth, mentioned examine co-author Beth Shapiro, a College of California Santa Cruz evolutionary geneticist.
Sometimes, a bear from elsewhere breeds with the southeast bear, however Shapiro mentioned it’s rare and solely one-way with no bear heading north and breeding with that inhabitants.
On the whole these bears are thinner than different Arctic bears, with females weighing about 400 kilos (185 kilograms), in comparison with 440 to 560 kilos (199 to 255 kilograms) elsewhere within the North American Arctic, Laidre mentioned. And so they additionally are likely to have fewer cubs, which might be as a result of they’re so remoted and don’t get as many mating alternatives, she mentioned.
As a result of this group hadn’t been studied earlier than, Laidre mentioned it’s not possible to inform if the Southeast Greenland polar bear inhabitants has simply tailored to be smaller and have fewer cubs or whether or not these are indicators of a harassed inhabitants and never a great signal for survival. Shapiro and others do not suppose it appears to be like good.
“They’re not reproducing as a lot as different people,” Shapiro mentioned. “They’re not as wholesome as different people who’re in a greater habitat. So it’s type of an oasis perhaps, but it surely’s not a cheerful oasis. It’s a I’m-struggling-to-get-by-but-just-making-it type of oasis.”
Lengthy-time polar bear scientist Steve Amstrup of Polar Bear Worldwide, who wasn’t a part of the examine, mentioned he worries that individuals will wrongly take this analysis to imply polar bears can adapt to local weather change, when it’s about one small group that’s prolonging their capability to persist, including that this “doesn’t supply salvation.” Whereas this group is distinct he mentioned he fears that calling consideration to it “could the truth is diminish the pure isolation they presently take pleasure in.”
This exhibits “that we are able to nonetheless actually have surprises,” Moon mentioned. “And I’m consistently reminded that there’s not ever some extent the place we throw within the towel.”
Comply with AP’s local weather protection at https://apnews.com/hub/local weather
Comply with Seth Borenstein on Twitter at @borenbears
Related Press local weather and environmental protection receives help from a number of non-public foundations. See extra about AP’s local weather initiative right here. The AP is solely answerable for all content material.
Copyright 2022 The Related Press. All rights reserved. This materials is probably not printed, broadcast, rewritten or redistributed.