CHURCHILL: He’s lying in the sun facing the waves, away from the ice. On rocks, its white fur is useless camouflage. For this enormously built male Canadian polar bear, life is now slowing down away from its prey, seals.
In northern Canada’s Hudson Bay, in midsummer, the last chunks of ice are like confetti in the blue expanse. All around, the coast is almost flat, made of rocks, tall grass, especially willows with purple flowers, and thin trees that struggle to grow in the wind.
This is a critical time for bears in the region. Every year from the end of June, when the ice disappears, they are forced to settle on this shore and start a period of fasting, which is increasingly long and dangerous for them.
Once on land, “bears typically have very few food options,” says Geoff York, a biologist at Polar Bear International (PBI).
This American comes several weeks a year to Churchill, a town at the entrance to the Arctic in the Canadian province of Manitoba, to follow the evolution of the endangered animal.
Here, it can be seen more easily than anywhere else on the ice, borrowing off-road vehicles adapted to the tundra or zodiacs in Hudson Bay. It was during one such expedition that an AFP team managed to track Geoff York in early August.
Next to the impressive male basking in the sun, a remnant of bone. But nothing that doesn’t satisfy this animal from about 3.5 meters to about 600 kilos.
“In some places they can find a beluga carcass or a careless seal close to shore, but most of the time they fast and lose about a kilo a day,” continues the scientist.
In the Arctic, global warming is three times faster than in other parts of the world, or up to four times faster, according to the latest studies. Gradually, the ice, habitat of the polar bear, disappears.
According to a report published in Nature Climate Change in 2020, this could mark the near extinction of this iconic animal: from 1,200 individuals in the 1980s, the polar bear population in western Hudson Bay has risen to around 800 today.
In summer, the ice begins to melt earlier and earlier and glaciation in winter occurs later: its entire annual rhythm is questioned by the effects of global warming.
The possibility of accumulating stores of fat – and calories – before the summer famine is reduced.
The polar bear – also called Ursus maritimus – is a meticulous carnivore, feeding mainly on the white blubber that envelops the seals’ bodies.
But now, in the summer, this arctic super predator sometimes comes to eat seaweed. Like this mother and her cub, seen not far from Churchill’s harbor, which calls itself the “polar bear capital”.
The off-ice limit “for females, responsible for feeding their young that are suckled up to two years, is about 117 days” against 180 for males, details American Steve Amstrup, chief scientist at PBI.
Thus, births drop and it is increasingly rare for females to give birth to three cubs, as used to happen before.
A whole world in decline that Geoff York, 54, knows by heart after more than 20 years of researching the Arctic for the environmental organization WWF and then PBI.
In Alaska, for example, where he kept a tenacious memory of the fangs planted in his leg during a capture. Or when he came face to face with a woman in a den he thought was empty. This calm man shouted that day “louder than ever” in his life.
Today, however, the polar bear is a colossus with feet of clay.
In Hudson Bay, “polar bears now stay on land an average of a month longer than their parents or grandparents.”
“This leads them, when they become physically weak, to take more risks to find food, including approaching humans.”
Patrols in the city
With binoculars in hand, provincial wildlife officer Ian Van Nest surveys the rocks around Churchill “where bears like to hide” several times a day.
In this town of 800 inhabitants, inaccessible by car, the bears acquired the habit of frequenting the garbage collection center a few years ago, an easy – but harmful – source of food for them.
They could be seen tearing up garbage bags, eating plastic or poking their noses into cans amid the burning garbage.
Since then, precautions have been taken. The dump is one of the best guarded places with cameras, fences and patrols.
Everywhere in the city, car and house doors remain open in case you have to take refuge there after a bad encounter with the largest land carnivore.
And here, on every wall, is the emergency number to reach Ian or his colleagues.
When the alert phone rings, they jump in, hop in their truck armed with a rifle and a spray can of repellent and bulletproof vest on their backs. Ian Van Nest, in his early thirties with a beautiful beard, takes his role very seriously, which has become crucial with the proliferation of plantigrades across the city.
“Sometimes you have to stun the bear, sometimes you just have to honk,” the father told AFP during an inspection. “If we have to get out of the car, we use deterrent bullets. We shoot close to him, we don’t want to hurt him.”
Some areas are monitored more closely, especially around the school in the morning before doors open “to make sure families are safe on the way.”
Last bad memory: In 2013, when a woman was seriously injured by a bear in front of her house, barely saved by her neighbor who came out in her pajamas armed with her snow shovel.
Sometimes the animal must be captured and flown north or put behind bars until winter.
Churchill’s only prison is for bears: 28 cells, sometimes full in the fall, when bears roam the city en masse, hoping the ice will recover in November.
“Planet Air Conditioning”
The polar bear case should alarm us because the Arctic is a good “barometer”, notes Flavio Lehner, professor of earth and atmospheric sciences at American Cornell University, also on the expedition.
Since the 1980s, sea ice has shrunk by nearly 50% in summer, according to the National Snow and Ice Data Center.
“We see here some of the most significant changes” in the world, says the Swiss scientist.
This region is essential on a larger scale because “it is a kind of air conditioning of the planet thanks to this important feedback mechanism of sea ice and snow in general”, from which the white mirror returns 80% of the sun’s radiation, cooling it down. oh, he explains.
When the Arctic loses this reflective ability, it has consequences for the global temperature as a whole.
So when sea ice melts, the much darker ocean surface that replaces it absorbs 80% of the solar radiation, accelerating warming, continues Flavio Lehner.
A few years ago, scientists feared that sea ice in the Arctic summer would quickly reach a climatic “tipping point” and disappear permanently above a certain temperature.
The latest studies show that the phenomenon is reversible. “If we manage to lower temperatures again, the sea ice will come back”, says the scientist.
However, in the region today “all ecosystems, without exception, are affected” by the effects of global warming, explains Jane Waterman, a biologist at the University of Manitoba.
The permafrost – ground that remains permanently frozen for two years in a row – has begun to thaw and in Churchill the contours of landscapes have already changed, damaging railroads and wildlife habitat.
The entire food chain is threatened, with the appearance of other animals, such as red foxes or wolves, that threaten Arctic species.
According to the Canadian scientist, from viruses and bacteria to whales, “nothing is spared from change”.
beluga summer refuge
Not even the belugas that in summer, by the tens of thousands, migrate from arctic waters to find refuge in Hudson Bay. These little white whales are everywhere you look in this blue expanse.
Advancing in small groups, on an incessant broom, they like to follow the boats of scientists who come to study them, seeming to take pleasure in displaying their large round heads and breathing a few centimeters from the observers.
The little ones, gray in color, rest on their mothers’ backs in this estuary with relatively warmer waters, where they can protect themselves from orcas and find abundant food.
But more generally, in “certain areas of the Arctic, the beluga doesn’t have as many prey at its disposal” as it used to, explains Valeria Vergara, an Argentine researcher who has devoted her life to studying these whales.
“The absence of sea ice prevents phytoplankton from surviving and therefore feeding zooplankton, which feeds the big fish”, explains the scientist from the Raincoast Conservation Foundation. Belugas need to dive much deeper to find their food, which consumes more energy.
And in Hudson Bay, a new danger awaits them: some climate models predict that by 2030, with the reduction of sea ice, ships will be able to sail there year-round.
However, noise pollution is a big problem for the species, nicknamed “sea canaries” as their communication develops (whistles, clicks, touches…). They “depend on sound to communicate, but they also locate themselves, find their way, find food…”, explains Valeria Vergara.
Thanks to the boat’s hydrophone, the “Barco Beluga”, conversations from the depths come to the fore. The 53-year-old researcher is able to privately recognize the cries of mothers to maintain contact with their young.
For a beginning ear, it’s a surprising, cacophonous set. A bustling community, no doubt. But until when, scientists are alarmed.
Far away from the ice floe, this summer we saw a beluga on the Seine in France and in May a polar bear in southern Canada.