Latest reports suggest that Polar bears in Canada’s Hudson Bay risk starvation as the climate crisis lengthens periods without Arctic Sea ice, despite the creatures’ willingness to expand their diets.
Polar bears use the ice that stretches across the ocean surface in the Arctic during colder months to help them access their main source of prey – fatty ringed and bearded seals. They would be expected to conserve their energy and even enter a hibernation-like state, In the warmer months when the sea ice recedes.
However, human-caused climate change is extending this ice-free period in parts of the Arctic – which is heating between two and four times faster than the rest of the world – and forcing the polar bears to spend more and more time on land.
A new research that looked at 20 polar bears in Hudson Bay suggests that without sea ice they still try to find food.
“Polar bears are creative, they’re ingenious, you know, they will search the landscape for ways to try to survive and find food resources to compensate their energy demands if they’re motivated,” Anthony Pagano, a research wildlife biologist with the US Geological Survey and lead author of the study, told AFP.
Read also: UN says migratory species increasingly under threat
The research, which was published in the journal Nature Communications, used video camera GPS collars to track the polar bears for three-week periods over the course of three years in the western Hudson Bay, where the ice-free period has increased by three weeks from 1979 to 2015, meaning that in the last decade bears were on land for approximately 130 days.
Among other things, the researchers found that of the group, two bears indeed rested and reduced their total energy expenditure to levels similar to hibernation, but the 18 others stayed active. The study said that these active bears may have been pushed to continue to look for food, with individual animals documented eating a variety of foods including grasses, berries, a gull, a rodent and a seal carcass.
Three ventured off on long swims – one travelled a total distance of 175km (more than a hundred miles) – while other bears spent time playing together or gnawing on caribou antlers, which researchers said was like the way dogs might chew bones.
But ultimately the researchers found that the bears’ efforts to find sustenance on land did not provide them with enough calories to match their normal marine mammal prey.
Nineteen out of the 20 polar bears studied lost weight during the period consistent with the amount of weight they would lose during a period of fasting, researchers said.
That means that the longer polar bears spend on land, the higher their risk for starvation.
Story was adapted from the Guardian.
