Walruses, weighing as a lot as 1,300 kilograms with enormous tusks and almost impenetrable skulls, are nearly inconceivable for a hungry polar bear to kill. However new analysis means that some polar bears have invented a work-around — bashing walruses on the top with a block of stone or ice.
For greater than 200 years, Inuit in Greenland and the jap Canadian Arctic have instructed tales of polar bears (Ursus maritimus) utilizing such instruments to assist in killing walruses. But explorers, naturalists and writers usually dismissed such accounts, relegating them to fantasy together with tales about shape-shifting bears.
The persistence of those studies, together with one report from an Inuk hunter within the late Nineties, coupled with photographs of a male polar bear named GoGo at a Japanese zoo utilizing instruments to acquire suspended meat compelled Ian Stirling and colleagues to research additional.
“It’s been my basic commentary that if an skilled Inuit hunter tells you that he’s seen one thing, it’s price listening to and really prone to be appropriate,” says Stirling, one of many world’s main polar bear biologists.
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The researchers reviewed historic, secondhand observations of device use in polar bears reported by Inuit hunters to explorers and naturalists in addition to latest observations by Inuit hunters and non-Inuit researchers and documented observations of GoGo and brown bears — polar bears’ closest kinfolk — utilizing instruments in captivity to entry meals. This evaluation suggests that device use in wild polar bears, although rare, does happen within the case of looking walruses due to their massive measurement, the researchers report within the June Arctic.
“Actually, the one species you’d need to bonk on the top with a chunk of ice could be a walrus,” says Andrew Derocher, director of the Polar Bear Science Lab on the College of Alberta in Edmonton, Canada, who wasn’t concerned with the brand new research. He suspects that it’d simply be a number of polar bears that do that habits. For instance, if a mom bear discovered the right way to use ice or stone on this approach, “it’s one thing her offspring would choose up on,” however not essentially a ability polar bears throughout the Arctic would purchase, he says.
Amongst animals, utilizing instruments to unravel issues has lengthy been considered a marker of a better degree of what people take into account intelligence. Notoriously good chimpanzees, for instance, craft spears to hunt smaller mammals (SN: 2/28/07). Dolphins carry marine sponges of their mouths to stir sand and uncover prey (SN: 6/8/05). And elephants have been identified to drop logs or massive rocks onto electrical fences to chop off the facility provide.
Research on the cognitive talents of polar bears are missing. “We don’t know something experimental or goal in any respect,” Stirling says. “Nonetheless, now we have a substantial amount of observational data that tends to counsel polar bears are actually good.”
Members of the bear household, Ursidae, are usually assumed to have robust cognitive abilities on account of their massive brains and evidenced by their subtle looking methods. Research on captive American black bears have even revealed some psychological capabilities that seem to exceed these of primates.
This sculpture within the Itsanitaq Museum in Churchill, Canada reveals a polar bear lifting a block of ice above the top of a sleeping walrus.Gloria Dickie
Gabriel Nirlungayuk, an Inuk hunter of Rankin Inlet in Nunavut, Canada, says he has heard such tales of polar bears utilizing instruments to hunt walruses. “I’ve seen polar bears since I used to be most likely 7 years previous. I’ve been round them, I’ve hunted alongside them, and I’ve seen their behaviors. The neatest hunters are often the feminine bears.” Generally, he says, polar bears will trick younger seals to return nearer by pretending to be asleep on the ice. Different occasions he’s noticed {that a} polar bear can sniff out a seal’s respiration gap in ice, even when it’s obscured by snow.
“I’ve labored with the Inuit on conventional information for a really very long time and one in all my favourite topics is polar bears, as a result of science usually suggests one factor and the Inuit say one other factor,” he notes.
There are round 26,000 wild polar bears residing in 19 subpopulations throughout the Arctic and sub-Arctic. The bears primarily eat seals, looking the marine mammals by staking out above their respiration holes. Due to local weather change, Arctic sea ice is quick disappearing, and scientists predict that many polar bear populations will likely be extinct by the century’s finish. Determined polar bears might more and more assault walruses, however “there are limitations to what number of walruses an grownup bear can take down,” says coauthor Kristin Laidre, an Arctic ecologist on the College of Washington in Seattle. It takes loads of power.
Following publication of the brand new research, Stirling obtained a video from U.S. Geological Survey scientist Anthony Pagano, based mostly in Anchorage, Alaska, who had beforehand connected a GoPro digital camera to a wild polar bear for a separate undertaking. That footage, Stirling says, reveals a feminine polar bear sliding a big block of ice round earlier than throwing it into the water at a seal.
