When a polar bear kills, it doesn’t simply eat. It feeds an entire ecosystem

When a polar bear kills its prey, it’s not the one one who will get to reap the bloody advantages.

Many of nature’s apex predators guard their dinner from scavengers till they’ve wolfed up each final morsel and licked the bones clear. But scientists say polar bars are inclined to eat what they want, and depart the remaining behind for different Arctic critters to munch.

A brand new research, published the journal Oikos, estimates that one polar bear offers roughly 300 kilograms of meat per 12 months for different animals to dine on. With 26,000 polar bears within the Arctic, that’s a whopping 7.6 million kilograms of meals yearly. 

“If we lose polar bears from the Arctic … nothing can replace that,” Holly Gamblin, wildlife biologist at University of Manitoba, instructed As It Happens host Nil Köksal. “There’s no other comparable species that is doing this.”

Sharing isn’t essentially caring

By sharing the spoils of the hunt, polar bears are offering what’s generally known as an “ecosystem service,” says Gamblin, the research’s lead writer. And it’s in stark distinction to the behaviours of many different high predators, like mountain lions and wolves. 

But polar bears, she says, aren’t doing this out of the kindness of their hearts. 

“I can’t say that they have this altruistic nature about them,” she stated. “But what they do have is this blubber specialist diet.”

Polar bears, she says, actually solely wish to eat one factor — and that factor is blubber, the thick layer of warming fats beneath the pores and skin of marine animals like seals and penguins.

“They’re usually stripping that first,” Gamblin stated. “They don’t really care so much about the meat that’s left over. It’s hard for them to digest that protein.”

Geoff York, a polar bear researcher who wasn’t concerned on this research, says polar bears will transcend the blubber in the event that they’re hungry sufficient, however they positively choose these fatty morsels.

“Much like brown bears along salmon streams become more selective as they gain weight, eating only the eggs of spawning salmon and leaving the carcass, polar bears in good body condition also focus on the fat from marine mammal prey,” York, director of analysis on the conservation group Polar Bear International, stated in an electronic mail.

And one Arctic carnivore’s trash is one other’s treasure.

The research, which incorporates scientists from the University of Alberta, confirmed 11 vertebrate species have been documented scavenging polar bears’ discarded meat, together with wolves, foxes, gulls, hawks, snowy owls and grizzly bears.

The group additionally recognized one other eight species as potential scavengers as a result of they have been noticed on the ocean ice, however have not been noticed consuming polar-bear cast-offs.

Chief among the many benefactors are Arctic foxes, who’re recognized to observe polar bear tracks approach out onto sea ice within the hope of snagging some meaty scraps.

“Arctic foxes are kind of considered the best friend of polar bears,” Gamblin stated. “So polar bears making kills and fattening up can actually impact Arctic fox populations from year to year.”

But polar bear populations are declining quickly. 

One research from final 12 months estimates that polar bears may disappear totally from Hudson Bay over the following couple of a long time due to melting sea ice from local weather change. 

Gamblin and her colleagues be aware that polar bear populations declined 32 per cent within the Western Hudson Bay between 1987 and 2011, and 44 per cent within the Southern Beaufort Sea between 2004 and 2016. 

Those losses alone quantity to 323,000 kilograms in misplaced meals assets for different Arctic animals, the research’s authors say.

That’s simply another reason why it’s vital to guard polar bears, says York.

“The potential loss of top predators is not about the loss of a single species, but the loss of a key player in the ecosystem that will have domino effects across the Arctic,” he stated.