At the end of the Canadian Arctic summer, polar bears head inland to wait for the ice to form.
And while thousands of tourists flock to catch a glimpse of these magnificent predators, researchers are developing novel ways to keep people and bears safely separated.
New tracking devices that stick in polar bears’ fur could be the key to protecting both people and bears – by closely monitoring the animals’ locations.
Polar bears now spend more of the year on land, as Arctic sea ice melts, so conservationists are increasingly concerned about bears and people coming into contact.
The tracking tags, which have been tested on bears in Canadian Arctic, could help prevent those encounters, by “keeping a remote eye” on the bears.
Lead researcher Tyler Ross, a PhD candidate from York University in Toronto, said the fur tags were “particularly promising” for the prevention of these “human-bear interactions”.
In communities in the southern Canadian Arctic, where the scientists tested these tags, polar bears that wander too close to a community are sometimes caught, transported and released in carefully selected sites away from towns and villages.
“These tags could be fitted to those bears to monitor where they are after they’ve been released,” explained Mr Ross.
“If they’re coming back towards the community, conservation staff would have a sense of where they are, and they could head them off. I think that’s where they offer considerable promise.”
The researcher, who studies polar bear ecology, also says the tags could fill important gaps in knowledge about the bears. And as the Arctic climate warms up rapidly, the need to monitor bears becomes increasingly urgent.
“There’s a dearth of information about male polar bear movements, because they can’t be equipped with conventional tracking collars,” said Mr Ross.
The sea ice [that the polar bears use as a platform from which to hunt] is disappearing faster than it has in the past,” explained Mr Ross. “So the winter hunting season is getting shorter. We want to know where they’re moving in response.”
Polar bears are difficult to tag. Male bears’ heads are smaller than their necks, so tracking collars can just slip off.
Another option is ear tags – attached by piercing the bear’s ear. They require an animal to be recaptured in order to remove the tag and, in rare cases, can injure the ear.
The three new tags the researchers tested were designed by the company 3M in collaboration with the charity Polar Bears International. They all attach to the bears’ coarse fur.
To fit the tags, scientists had to locate and sedate bears. They then assessed the quality of the data they received from each device and noted when the tags fell off.
The best performing device was called a SeaTrkr tag, which is “crimped” into the bears’ fur. It stayed attached for an average of 58 days and – with an in-built GPS system – allowed the scientists to pinpoint the bears’ location to within just a few metres.
“It’s ideal to have something that falls off naturally – that’s not permanently attached to the bear,” explained Mr Ross. “But anything that lasts in the order of a few months would be great [for our research], because then you’re getting these important seasons that the bears are going through throughout the year.”
Climate change is bringing bears and humans into closer proximity, making places where polar bears and people coexist, riskier for both.
One US Geological Survey study in 2022 that that used data from satellite tracking collars on more than 400 polar bears in Alaska, shows the time they spend onshore has grown significantly in recent decades.
“Getting a better sense of polar bears’ movements is really crucial,” Mr Ross commented. “Particularly given the state of their environment at this point.”
This study of the bear tags is published in the journal Animal Biotelemetry.