Polar bear biopsies to shed light on Arctic pollutants
With one foot braced on the helicopter's landing skid, a veterinarian lifted his air rifle, took aim and fired a tranquiliser dart at a polar bear.
The predator bolted but soon slumped into the snowdrifts, its broad frame motionless beneath the Arctic sky.
The dramatic pursuit formed part of a pioneering research mission in Norway's Svalbard archipelago, where scientists, for the first time, took fat tissue biopsies from polar bears to study the impact of pollutants on their health.
The expedition came at a time when the Arctic region was warming at four times the global average, putting mounting pressure on the iconic predators as their sea-ice habitat shrank.
"The idea is to show as accurately as possible how the bears live in the wild -- but in a lab," Laura Pirard, a Belgian toxicologist, told AFP.
"To do this, we take their (fatty) tissue, cut it in very thin slices and expose it to the stresses they face, in other words pollutants and stress hormones," said Pirard, who developed the method.
Moments after the bear collapsed, the chopper circled back and landed. Researchers spilled out, boots crunching on the snow.
One knelt by the bear's flank, cutting thin strips of fatty tissue. Another drew blood.
Each sample was sealed and labelled before the bear was fitted with a satellite collar.
Scientists said that while the study monitors all the bears, only females were tracked with GPS collars as their necks are smaller than their heads -- unlike males, who cannot keep a collar on for more than a few minutes.
- Arctic lab -
For the scientists aboard the Norwegian Polar Institute's research vessel Kronprins Haakon, these fleeting encounters were the culmination of months of planning and decades of Arctic fieldwork.
In a makeshift lab on the icebreaker, samples remained usable for several days, subjected to controlled doses of pollutants and hormones before being frozen for further analysis back on land.
Each tissue fragment gave Pirard and her colleagues insight into the health of an animal that spent much of its life on sea ice.
Analysis of the fat samples showed that the main pollutants present were per- and polyfluoroalkyl substances (PFAS) -- synthetic chemicals used in industry and consumer goods that linger in the environment for decades.
Despite years of exposure, Svalbard's polar bears showed no signs of emaciation or ill health, according to the team.
The local population has remained stable or even increased slightly, unlike parts of Canada, where the Western Hudson Bay group declined by 27 percent between 2016 and 2021, from 842 to 618 bears, according to a government aerial survey.
Other populations in the Canadian Arctic, including the Southern Beaufort Sea, have also shown long-term declines linked to reduced prey access and longer ice-free seasons.
Scientists estimate there are around 300 polar bears in the Svalbard archipelago and roughly 2,000 in the broader region stretching from the North Pole to the Barents Sea.
The team found no direct link between sea ice loss and higher concentrations of pollutants in Svalbard's bears. Instead, differences in pollutant levels came down to the bears' diet.
Two types of bears -- sedentary and pelagic -- feed on different prey, leading to different chemicals building up in their bodies.
- Changing diet -
With reduced sea ice, the bears' diets have already started shifting, researchers said. These behavioural adaptations appeared to help maintain the population's health.
"They still hunt seals but they also take reindeer (and) eggs. They even eat grass (seaweed), even though that has no energy for them," Jon Aars, the head of the Svalbard polar bear programme, told AFP.
"If they have very little sea ice, they necessarily need to be on land," he said, adding that they spend "much more time on land than they used to... 20 or 30 years ago".
This season alone, Aars and his team of marine toxicologists and spatial behaviour experts captured 53 bears, fitted 17 satellite collars, and tracked 10 mothers with cubs or yearlings.
"We had a good season," Aars said.
The team's innovations go beyond biopsies. Last year, they attached small "health log" cylinders to five females, recording their pulse and temperature.
Combined with GPS data, the devices offer a detailed record of how the bears roam, how they rest and what they endure.
Polar bears were once hunted freely across Svalbard but since an international protection agreement in 1976, the population here has slowly recovered.
The team's findings may help explain how the bears' world is changing, and at an alarming rate.
As the light faded and the icebreaker's engines hummed against the vast silence, the team packed away their tools, leaving the Arctic wilderness to its inhabitants.
olm-ef/po/srg/jj/gil
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


Washington Post
9 hours ago
- Washington Post
NIH scientists go public to criticize Trump's deep cuts in public health research
WASHINGTON — In his confirmation hearings to lead the National Institutes of Health, Jay Bhattacharya pledged his openness to views that might conflict with his own. 'Dissent,' he said, 'is the very essence of science.' That commitment is being put to the test. On Monday, scores of scientists at the agency sent their Trump-appointed leader a letter titled the Bethesda Declaration, a frontal challenge to 'policies that undermine the NIH mission, waste public resources , and harm the health of Americans and people across the globe.'


CNN
20 hours ago
- CNN
New tech reveals never-before-seen details in solar corona
A breakthrough in adaptive optics technology captured the clearest images to date of the sun's corona. The incredible resolution of the new images could provide new insights on some of the mysteries surrounding our star.
Yahoo
a day ago
- Yahoo
Astronomers finally figured out how Pluto cools itself
If you purchase an independently reviewed product or service through a link on our website, BGR may receive an affiliate commission. Pluto might be small and distant, but it keeps surprising scientists. After the New Horizons spacecraft zipped past it in 2015, we got our first real look at its icy landscape and unexpectedly active atmosphere. But even with those discoveries, one question lingered in scientists' minds. How does Pluto regulate its temperature with such a strange environment? Well, thanks to new data from the James Webb Space Telescope, researchers say they may have found the answer, and it's pretty wild. Where most planets rely on gases in the atmosphere to regulate their temperatures, researchers believe that Pluto cools itself using haze particles. Today's Top Deals Best deals: Tech, laptops, TVs, and more sales Best Ring Video Doorbell deals Memorial Day security camera deals: Reolink's unbeatable sale has prices from $29.98 See, Pluto's atmosphere is incredibly thin and made mostly of nitrogen, with traces of methane and carbon monoxide. What makes it special isn't just its composition, but the presence of a constant haze. This haze is made up of tiny particles, and if the data from James Webb is correct, it does more than just drift around in the cold. Normally, planetary atmospheres manage temperature through movement and properties of gas molecules, as I mentioned before. But Pluto cools itself differently. As sunlight hits the planet, the haze particles absorb energy and rise. When they cool, they sink again. This up-and-down cycle helps manage the planet's heat, keeping the atmosphere in a delicate balance. No other world cools itself this way, as far as we know. The idea is kind of crazy, but it also isn't unprecedented. Researchers actually proposed it a few years ago, before we had any proof. That's where James Webb comes in. Recent observations focused on Pluto using mid-infrared wavelengths. The telescope detected the exact type of thermal signals that scientists had predicted. The haze in Pluto's atmosphere was indeed radiating heat, just as the theory suggested it would. But these findings tell us more than how Pluto cools itself. They will also force scientists to rethink what's possible for other hazy worlds. Moons like Titan and Triton, for instance, also have nitrogen-heavy atmospheres and thick hazes. They could be managing their heat in similar ways. There's also a deeper link to our own planet. Researchers say Earth's early atmosphere may have looked more like Pluto's, filled with nitrogen and hydrocarbons. By studying how Pluto's haze behaves, researchers might uncover clues about how conditions to support life first formed here on Earth. More Top Deals Amazon gift card deals, offers & coupons 2025: Get $2,000+ free See the