Melting sea ice is forcing
polar bears on to dry land – and, increasingly, into contact with humans
Suzanne Goldenberg in Churchill, Manitoba
theguardian.com, Wednesday 27 November 2013/ http://www.theguardian.com/environment/2013/nov/27/canada-living-with-polar-bears-climate-change
It was just a few days after a polar bear had mauled two
people in the centre of town that the patrol officer pulled up by the school
and scanned his binoculars along the rocky shoreline of Hudson Bay looking for
any signs of a telltale white lump.
"There could be a bear, or several bears, right there
hiding in the willows and you wouldn't even know it," said Bob Windsor,
the officer for Manitoba Conservation. He had received three reported sightings
in town that morning; there could be up to 20 on a typical November day.
Such is life in Churchill, a town with about as many polar
bears as people.
But living with polar bears is growing more risky, for both
species, in a future being written by climate change. The loss of sea ice has
already caused a precipitous drop in the bear population around Hudson Bay,
forcing bears off their platform for hunting seals – their main source of food.
The ice season in Hudson Bay has fallen by about one day
each year over the past three decades, interrupting the polar bears' prime
feeding season in the spring and keeping them off the ice longer into the
autumn and winter.
Scientists say the starving bears are resorting to risky and
atypical behaviours, such as cannibalism, and are wandering far inland, where
they come into closer proximity with people in the small communities across the
north.
For Windsor, who has a bandolier of shotgun shells slung
around the seat of his truck, meeting a bear is all in a day's work. The
officer, equipped with scare pistol armed with blanks, an array of
firecrackers, an air horn and a paintball gun, spends his nights and days
herding polar bears out of town and back on to the tundra.
"The bears that we deal with in our programme, we are
teaching them to be scared of people," Windsor says. "Every bear that
we chase, maybe we are helping out somebody down the line that encounters a
bear, because it recognises that that's a person – and that is something to be
scared of."
But Windsor's job is expected to grow more difficult with a
warming Arctic. Local people in Churchill, and aboriginal hunters in the
self-governing territory of Nunavut, report a rise in sightings of bears near
communities in recent years.
Most encounters between the people of Churchill and the
polar bears have been near misses – like the case of the woman who threw a bag
of groceries at a bear to chase it away, and a man who distracted a bear from
his two young children by swatting the animal with a dog leash. By the first
week of November, there had been 168 such harmless incidents in Churchill this
year. Most of those bears were sub-adult males. "Think of them as
teenagers," said Daryll Hedman of Manitoba Conservation. "They are
the ones that seem to get themselves into trouble."
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Polar bears playing in Hudson Bay. Photograph: Rex Features
About a dozen polar bears that had been caught in town and
resisted officers' efforts to chase them away were confined to a polar bear
jail until they could be returned to the wild.
But in the pre-dawn hours of 1 November, an intruding polar
bear ripped the ear of a young woman making her way home from a Halloween party
and then pounced on a neighbour who came to her rescue, badly lacerating his
head and torso.
The attack occurred in front of a dozen onlookers, who
screamed, banged pots and pans, let off firecrackers and shot at the bear
repeatedly – without effect. "My heart was pounding out of my chest,"
said Didier Foubert-Allen, another neighbour. "I shot at the bear maybe
four times when I realised it was not going anywhere."
The bear,now streaked with blood, ran off only when
Foubert-Allen ran for his truck and charged the bear with lights blazing and
horn blaring.
Scientists predict a rise in such encounters across the
north, with the melting of the sea ice. Wildlife managers across the polar
region are already planning for a future of rising encounters between polar
bears and humans.
The governments of America and Norway are working to
assemble a database of bear attacks across all five polar range territories –
Alaska, Canada, Greenland, Norway, and Russia – in anticipation of a rise in
such conflicts.
To date, there are 110 recorded instances of polar bear
attacks causing severe injury. James Wilder, the US fish and wildlife agency
biologist overseeing the registry, said that number should be set against the
"thousands and thousands – probably tens of thousands – of nonviolent
encounters with polar bears" across the north.
Until this autumn, Churchill had a fairly peaceful history
of living with polar bears, with only two recorded fatalities attributed to
attacks from the creatures since 1717.
Conservation officials in Churchill and Nunavut are working
on early-warning systems for intruding polar bears, such as radar or
sophisticated ear tags. Last year, officials in Churchill fitted one of the
town's worst nuisance bears – an adult male known locally as Lardass – with an
ear tag fitted with a VHF transmitter.
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One of many polar bear alert warning signs in Churchill.
Photograph: Paul J Richards/AFP/Getty Images
The device was designed to send a text message to conservation
officials if Lardass wandered towards town, allowing the bear patrol to
intercept the repeat offender. However, the tag fell off and the bear patrol
lost track of Lardass until late September.
Some American polar bear scientists have proposed Churchill
residents make greater use of bear spray. Such irritant sprays are commonly
used in wilderness areas of Alaska and other places where there is a risk of
running into grizzlies.
Officials and conservation groups are also revisiting the
once taboo notion of taking adult bears who are repeat offenders to the zoo,
rather than killing the animals to reduce the risk to humans. The notion would
upset the idea of only consigning orphaned cubs to a lifetime in captivity, and
remains highly controversial.
"It is not know how well an adult bear would adapt to a
captive life but in this situation where the choice is death by euthanasia,
maybe it's a reasonable thing to try to see if it could be happy in a captive
setting," said Geoff York of WWF.
But authorities are increasingly going to have to confront
such difficult situations, as melting sea ice forces polar bears off their
traditional platforms for hunting seal on to dry land. The decline of the sea
ice and the shortage of food are cutting into the birth rate for female polar
bears, threatening the survival of cubs and leading to strange or dangerous
behaviour.
"Where really good research has been done, we find
bears that are nutritionally stressed or otherwise desperate will try things
that are risky," said Tom Smith, a wildlife biologist at Brigham Young
University who studies human-bear interactions.
Researchers have seen evidence of cannibalism, which was
previously unknown, and greater movement inland by polar bears, which
ordinarily stay within five miles of the coast. There had been at least one
recent incident of a polar bear travelling as far as 250 miles inland in
search of food, Smith said.
The most dangerous behaviour of all, however, may be coming
into contact with humans. Scientists expect that, too, to rise, as the polar
bears are pushed off the ice. "When we see bears attacking people that is
a very good sign that these are bears that are on the edge," said Smith.
For the moment, Churchill is holding its own. The town is
seen as a model of human-polar bear coexistence. Children are trained in polar
bear safety, and at the height of the season, Windsor and his colleagues are on
24-hour shifts.
But the polar bear alert programme Churchill is so proud of
is operating on a tiny budget: just $95,500 (£59,000).
The authorities have already been forced to turn to tourists
and television crews to "sponsor" expensive helicopter airlifts of
animals from the polar bear jail back into the wild.
And so long as there remains seasonal ice in Hudson Bay, the
town expects to continue seeing polar bears. Michael Spence, the mayor,
acknowledges it is impossible to guarantee there will never be another polar
bear attack in the town – especially in a future under climate change.
"You can't close every street. You can't fence the
community," he said.
Encounters with polar bears were a fact of life, Spence said
– even those that resulted in violence.
"The unfortunate part is, it is going to happen,
because of where we live: we coexist," Spence said. "I think it's
just like rolling dice: it will happen, but it's when it will happen."
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