In current years, polar bears within the Beaufort Sea have needed to journey far outdoors of their conventional arctic searching grounds which has contributed to an nearly 30% lower of their inhabitants.
The bears’ residence vary, or the quantity of space they want for meals and different sources, was round 64% bigger from 1999-2016 than it was in 1986-1998, in line with a current research within the journal Ecosphere.
“Having to travel farther means these bears are expending more energy which can threaten their survival,” stated Anthony Pagano, a postdoctoral researcher in Washington State University’s School of the Environment and lead writer of the research. “If we want to preserve the habitat of these amazing mammals, then we need to focus on the root of the problem, which is slowing global climate change.”
For the research, Pagano and colleagues from the U.S. Geological Survey used satellite monitoring knowledge to investigate the motion patterns of feminine polar bears from 1986-2016 within the Beaufort Sea space north of Alaska.
Their work confirmed over the past twenty years polar bears are having to journey farther north of their conventional searching grounds on the continental shelf to stay on their receding sea ice habitat.
Extending round 100 miles north of Alaska and Canada, the continental shelf is a shallow water habitat that comprises loads of fish for the bears’ favourite prey, seals.
During the early summer when seals are weaning their pups and most susceptible to assault, polar bears will typically double their physique weight from consuming the fatty meat.
The researchers’ knowledge exhibits that as the ocean ice over the continental shelf continues to recede earlier and additional; the bears are being displaced from this main foraging habitat and touring additional north into deeper waters the place there are fewer seals to prey on.
“The combined impact of having to move farther and farther north with the ice in the summer and then having to move back in the fall and winter as the ice freezes is taking a major toll,” Pagano stated. “Our work highlights the worrying impact of sea ice decline on polar bear movement patterns.”
Another attention-grabbing discovering of the research is that round 20% of the polar bear inhabitants within the Beaufort Sea is foregoing their conventional sea ice searching grounds altogether in the summertime and fall. These bears are shifting inland alongside the Alaskan and Canadian coast on the lookout for meals resembling carrion, berries and generally even bowhead whale carcasses which are left on the shore by indigenous residents that hunt the big aquatic mammals.
“Sometimes you’ll have 50 to 100 polar bears that congregate around these whale carcasses and compete with each other for food,” Pagano stated. “As more and more bears move on land, I suspect there’ll be a lot more competition for these food resources and we’ll probably start seeing further decreases in abundance and survival.”
Moving ahead, Pagano and his colleagues with the U.S Geological Survey plan to conduct additional research of the polar bears shifting inland to get a greater concept of how they’re dealing with their new terrestrial habitat.
He stated the most effective factor people can do to assist protect the southern Beaufort Sea’s 800 or so remaining polar bears is to concentrate on curbing world carbon emissions that are the principle trigger behind receding arctic sea ice.
Recent modeling work has proven that if laws are enacted to cut back these emissions to keep away from world warming larger than 2°C or 3.6°F then it might drastically gradual the decline of polar bear habitat within the arctic which might in flip assist these animals to outlive.
“Coming across a polar bear while flying over the arctic in a helicopter is a surreal experience,” Pagano stated. “They are incredibly massive and impressive. It is amazing to observe this animal that is so uniquely adapted to exist in this harsh arctic environment. They are worth the effort it will take to preserve them.”
Anthony M. Pagano et al, Effects of sea ice decline and summer time land use on polar bear residence vary dimension within the Beaufort Sea, Ecosphere (2021). DOI: 10.1002/ecs2.3768
Citation:
Melting sea ice forces polar bears to journey farther for meals (2021, December 14)
retrieved 14 December 2021
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