Polar bears face decimation because of the warming planet
Endgame for polar bears as Arctic habitat melts away
24th August, 2011
The recent polar bear attack in Norway is the latest reminder that time is running out for these iconic mammals, with runaway climate change and habitat loss. Gavin Haines reports
I was awoken suddenly by what sounded like firecrackers going off. They were coming from outside, but as I peered through the curtains of my hotel room, the streets of Churchill, Canada appeared calm and quiet; I went back to sleep questioning whether it was a dream.
Later, over breakfast, I’m told that my ears weren't mistaken; a marauding polar bear had ventured into town at dawn, forcing locals to set off firecrackers in a bid to scare it off. Residents were on high alert; the day before another bear had chased a man through the coastal town, which sits on the edge of the Hudson Bay, and very nearly caught him.
'A guy was taking photographs on the beach when this polar bear appeared and started chasing him,' explains Hayley Shephard, my tour guide in Churchill.
'Fortunately the rangers were nearby so they drove their vehicle between the bear and the man but the bear became aggressive and smashed the hood – they ended up shooting it.'
As I listened to tales of close encounters in Canada, over in Norway a group of British students were embarking on an ill-fated trip into the Arctic.
It was, tragically, an adventure they didn’t all return from; in the night a polar bear crept into their camp and attacked the young explorers in their tents, killing 17-year-old Horatio Chapple and leaving several others seriously injured. The bear was shot dead and a post-mortem revealed it was eight stone underweight, just like the malnourished bear that was shot in Churchill.
It’s an all too familiar story; as temperatures in the Arctic rise, the ice, which bears use as hunting platforms, is melting sooner every year. This leaves them with less time to build up their fat reserves before an increasingly long and hungry summer.
'A compressed feeding schedule is the biggest threat to them,' explains Duane Collins, a guide for Parks Canada, who I meet later that day. 'Without ice they can’t hunt'
According to Duane, the Hudson Bay has lost about three weeks of ice coverage in recent decades. 'Every week the bears aren’t on ice they lose about 10kg of fat,' he says. 'And bears that aren’t fat enough can’t conceive; the fertilised eggs hang in suspended animation until the bear is fat enough and if that doesn’t happen she will self-abort.'
As Duane guides me around Churchill’s heritage centre, he shares his worst fears with me. 'Polar bears in West Hudson Bay are in decline; numbers have decreased by 25 per cent in the last 20 years' he says.'Scientists think that soon the area could stop being a habitat for the bears.'
One of those scientists is Dr. Steven Amstrup, who works for Polar Bears International; a non-profit organisation dedicated to protecting the world’s 25,000 odd polar bears. 'Some of this disappearance will be due to starvation and some due to the migration of bears to higher latitudes and cooler conditions,' says the US based scientist. 'The sea ice there is not persistent for long enough to support them anymore.'
Researchers for the US Geological Survey agree. They've been studying populations in Alaska, which are also shrinking and believe diminishing sea ice is forcing bears to swim greater distances, which burns precious calories and frequently claims the lives of their cubs.
One female bear they tracked swam an incredible 426 miles in nine days, without any ice to rest on. And that’s not all; she then walked and swam a further 1,118 miles, an epic odyssey that took her just two months to complete. However, it didn't come without a price; she lost her cub along the way and when scientists recaptured the bear she’d lost nearly a quarter of her body weight.
While some bears embark on mammoth journeys in search of food, others, as recent events have highlighted, are drawn to human settlements. So can we make any links between recent attacks in Norway and Canada with global warming? 'We cannot link any one particular incident to global warming,' explains Dr. Amstrup.
'However, we have long predicted that negative interactions between bears and people can only increase as the bears are stressed nutritionally; one consequence of that will be more attacks by bears on people and domestic animals.'
Despite the gloomy predictions, Churchill still proudly claims to be the 'polar bear capital of the world.' It has to; the town’s economy relies on tourists coming to see them. Most visitors come in March, which is the beginning of bear season. 'In December, mother bears make an underground den and give birth inside,' says Duane. 'The insulated peat and snow keeps the temperature inside the den at -1 degrees compared to around -40 degrees outside.'
When the worst of the winter is over, in March, the mother and her cubs break out the den and go hunting. And the father? He disappeared long ago, leaving mum to raise the cubs. 'March is the most important time of the year for bears because that’s when the baby ring seals are born,' explains Duane. 'They are the polar bear’s primary prey source.'
Although it was now summer in Churchill, and the ice and snow had melted away, I still had a fairly high chance of seeing polar bears; some were still completing the swim from their now-melted ice platforms to the coast, while others were conserving energy on land.
Eager to spot one of these magnificent beasts, I arrange a boat trip into the Hudson Bay. As Hayley drives me to the town’s small, industrial port, she tells me what to do if ever I get chased by a polar bear. 'Take off your clothes while you’re running away,' she says. 'It buys you time because the bears stop to sniff them. And when you arrive at someone’s house stark naked, knocking at the door, they won’t ask any questions, they’ll let you in because they’ll know a polar bear is after you.'
At the port we meet a local legend called Mike Macri, who operates boat trips in the Churchill Estuary, which is where the River Churchill meets the Hudson Bay. Mike had been described to me as a true bushman, a title borne out of the fact he has been known to disappear into the Arctic, mid winter, for weeks on end to live in igloos and take photographs of bears. He’s pleasant chap of few words and he doesn't want to hang around.
'We need to go,' he says, gesturing towards the boat. 'There were some bears at Eskimo Point this morning – let’s go and see if we can find them.' It’s a short and relatively calm journey to Eskimo Point and when we get there, sure enough, there’s a bear relaxing on the rocks. To me it’s a magnificent spectacle but Mike isn’t happy. 'That one looks kind of skinny,' he says, shaking his head. 'That’s not a healthy polar bear.'
Coincidentally, as Mike and I looked for polar bears, the Canadian government were announcing plans to list them as a species at risk. For many it’s an overdue acknowledgement that this iconic mammal is under threat, but not everyone welcomed the news; the Inuit (first nation) populations are worried this will impact on their rights to hunt polar bears, which they have done since their ancestors first stepped foot on the chilly land.
Furthermore, many Inuit claim bear numbers in northern regions are actually increasing and disagree that the species should be added to the list. While Dr. Steven Amstrup doesn’t have sufficient evidence to confirm whether or not bear numbers in the north Arctic have increased, he warns it is likely to be a short tem trend.
'At the northern extremes of the polar bear's current range, where sea ice historically has been too heavy for too long, polar bears may benefit from a somewhat milder climate,' he says. 'However, any improving trend will be transitory.' In other words, while northern bears might benefit from a warming climate initially, eventually they will become a victim of it.
A happy ending?
As Mike and I cruise back to the port, we spot another bear lumbering over the rocks. We get close enough for a good look, but keep our distance to avoid aggravating it. 'That’s more like it,' says Mike, peering through binoculars. 'He’s got a good gut on him.'
It was my last day in Churchill and seeing this fat, healthy bear it felt as though my trip had a happy ending. But, sadly, that isn’t the end of the story for the world’s polar bears, because unless climate change is halted or reversed, the species’ days are numbered. 'The only way to save the bears and their sea ice habitats is to control temperature rise through greenhouse gas mitigation,' explains Dr. Amstrup.
'Without such mitigation, polar bears will be expected to occur only in increasingly northerly climes until they ultimately wink out. When the last vestiges of ice are gone, so will be the polar bears.'
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