Climate crisis may be pushing polar bears to drown reindeer for food
Josh Marcus
Mon, November 29, 2021
Polar bears have been spending more time on land as the climate crisis causes see ice to melt (China News Service via Getty Ima)
The climate crisis may be pushing polar bears to use new tactics to seek out unexpected sources, including drowning reindeer, according to researchers.
In 2020, Polish researchers captured what’s believed to be the first ever recording of a polar bear drowning a reindeer, which they described in a recent article in the journal Polar Biology.
The clip, filmed by Mateusz Gruszka on Norway’s frigid Svalbard archipelago, shows a polar bear that appears in “excellent condition” swimming after a reindeer, which it drowns then drags to shore.
The tactic suggests that the bears, increasingly pushed to spend more time on land because of melting polar ice caps, are seeking out other food sources to replace their usual diet of fat-rich seals.
“In recent decades, more polar bears have been forced to remain longer on land, so their access to seals is limited,” the researchers write, though they caution “the importance of terrestrial food to polar bears is disputable, and more data are needed.”
Polar bears weren’t known to hunt reindeer in large numbers before 2000, as global heating became unignorable, and reindeer remains began showing up in “high frequency” in polar bear scat, according to the researchers.
Svalbard, home to a population of about 300 polar bears, could become a regular reindeer hunting ground.
“If polar bear mothers learn to hunt reindeer efficiently, their offspring, which stay with their mothers for over two years, may also become reindeer hunters,” the researchers add.
The climate crisis could also push the bears to seek out other opportunistic food sources, such as dead fish and cetaceans washed ashore, rodents, offal from landfills, and the leftover remains of marine mammals hunted by humans.
Josh Marcus
Mon, November 29, 2021
Polar bears have been spending more time on land as the climate crisis causes see ice to melt (China News Service via Getty Ima)
The climate crisis may be pushing polar bears to use new tactics to seek out unexpected sources, including drowning reindeer, according to researchers.
In 2020, Polish researchers captured what’s believed to be the first ever recording of a polar bear drowning a reindeer, which they described in a recent article in the journal Polar Biology.
The clip, filmed by Mateusz Gruszka on Norway’s frigid Svalbard archipelago, shows a polar bear that appears in “excellent condition” swimming after a reindeer, which it drowns then drags to shore.
The tactic suggests that the bears, increasingly pushed to spend more time on land because of melting polar ice caps, are seeking out other food sources to replace their usual diet of fat-rich seals.
“In recent decades, more polar bears have been forced to remain longer on land, so their access to seals is limited,” the researchers write, though they caution “the importance of terrestrial food to polar bears is disputable, and more data are needed.”
Polar bears weren’t known to hunt reindeer in large numbers before 2000, as global heating became unignorable, and reindeer remains began showing up in “high frequency” in polar bear scat, according to the researchers.
Svalbard, home to a population of about 300 polar bears, could become a regular reindeer hunting ground.
“If polar bear mothers learn to hunt reindeer efficiently, their offspring, which stay with their mothers for over two years, may also become reindeer hunters,” the researchers add.
The climate crisis could also push the bears to seek out other opportunistic food sources, such as dead fish and cetaceans washed ashore, rodents, offal from landfills, and the leftover remains of marine mammals hunted by humans.
Disturbing theory behind 'rare' polar bear video
Michael Dahlstrom
·News and Video Producer
Mon, November 29, 2021
This article originally appeared on Yahoo News Australia.
WARNING – DISTURBING CONTENT: Video of a polar bear attacking and killing a reindeer shows how the species are adapting their diet.
Polish scientists stationed in Norway's Svalbard archipelago believe this is the first time such an interaction has been captured on film.
Shaky hand-held-footage shot in 2020 shows the apex predator swimming closely behind its frightened prey.
The adult female then pulls the reindeer underwater and drowns it.
A polar bear has been filmed chasing down a reindeer. Source: AFP / Izabela Kulaszewicz
Moments later the bear can be seen dragging its lifeless prey onto the rocky shore.
Images published in the journal Polar Biology show the reindeer being consumed and the remains buried.
Polish scientists said the bear was observed using “much the same method” to kill reindeer twice, leading them to hypothesize it could be becoming “specialized” at hunting the species.
With reindeer outpacing polar bears on land, forcing the reindeer into water could be giving giving the predator an advantage.
Climate crisis forcing polar bears to adapt their diet
As sea ice melting worsens across the Arctic due to global heating, researchers have observed polar bears are spending more time on land around Svalbard.
This is limiting the bears’ access to their primary prey, seals, forcing them to look for land-based high-calorie food sources.
Polar bears are classified as marine mammals due to their habitat and food sources, so their changing behaviour could one day lead to an adjustment as to how scientists categorize them.
Researchers studying the animals did not find evidence that polar bears had been hunting reindeer before 2000, but by 2013 their remains were found in "high frequency" through their scats.
They theorize that reindeer could increasingly be forming a regular part of polar bear diets.
Concern for future of polar bears despite signs of adaption
Studies have indicated polar bears have lost weight attempting to adapt to land-based food sources, however the animal filmed killing the reindeer appeared to be in "excellent condition".
Despite not being as fatty as seals, reindeer appear to be an increasingly important food source during the summer months.
The region is home to around 300 polar bears who have been observed passing down the same hunting grounds for generations.
Reindeer numbers are increasing across Svalbard. Source: Getty
“If polar bear mothers learn to hunt reindeer efficiently, their offspring, which stay with their mothers for over two years, may also become reindeer hunters,” researchers said.
Scientists believe their impact on the island’s birds will also likely increase, however seals will continue to be a key food source during spring and early summer.
Despite their success at hunting terrestrial prey, as sea ice continues to retreat the seal hunting season will become shorter, and there will likely be a tipping point when polar bears will struggle to further adapt.
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