The story of these unknown, isolated and surprising polar bears will certainly shock you.

Loose polar bears They are very special animals that suffer serious consequences climate change. A few years ago, a group of scientists discovered a group of these enormous ursids living in very special conditions that could change all the views we had about this species.

Newly documented group of polar bears that have uniquely adapted to their environment

One of the most iconic images of the climate crisis is that of a starving and malnourished polar bear, photographed on the Spitsbergen archipelago. It went around the world in 2015 polar bears are dependent on the Arctic sea ice, which is rapidly disappearing due to the global warming. The concerns are therefore more than justified.

In Greenland, there is a team of scientists who have documented a subpopulation of polar bears hitherto unknown. This lives in the southeast of the archipelago. And they only have access to sea ice for four months. Between February and the end of May.

The surprising thing about these animals is that they survive with limited access to this type of ice. And they hunt in the fresh water that flows into the ocean from Greenland’s glaciers. They are the most genetically isolated population of polar bears on the entire planet.

Getting information

As a preliminary step to field work, the researchers collected information from hunters for two years. They participated in all phases of the research and contributed their experiences. And providing samples for genetic analysis. “To address the situation of the polar bears In this area we started by asking the hunters to send us a tooth and the tip of the tongue from each bear hunted. The tooth to calculate age and the tongue for genetic analysis.

We have received these samples since 2011 and they are part of the data analyzed in the study published in Science.” This is explained by Fernando Ugarte, a Mexican biologist at the Greenland Institute of Natural Resources. Ugarte moved to Greenland in 2005.

The research is part of a broader project to advise the country’s government. The government is in favor of the conservation and sustainable use of polar bears in the east of the island. “This is important because there are people whose livelihoods depend on hunting these bears. And because the polar bears They are also affected by the pollution which comes from industrialized countries and as a result of global warming,” the scientist argues.

A population of polar bears well known to locals

What’s new is that scientists are now aware that there are two populations of them polar bears separated, in eastern Greenland, and not one as they previously believed. That is, there are six populations in the country, not five, and twenty in the world, instead of 19.

“We knew there were some polar bears in the area due to historical records and indigenous knowledge. “We just didn’t know how special they were,” said lead author Kristin Laidre, a polar researcher at the Applied Physics Laboratory at the University of Washington (US).

Sea ice provides the platform for most of the approximately 26,000 polar bears of the Arctic where seals used to be hunted. However, these bears in southeastern Greenland have adapted their survival to a different strategy: they hunt seals between patches of freshwater ice that break off from the Greenland ice sheet.

Years of tracking polar bears under extreme conditions

The second step of the evaluation was a local knowledge survey, which they conducted in late 2014 and early 2015. They contacted hunters who had reported the most bears in the five years between 2009 and 2013 and asked them several questions about the climate. animals and hunting.

“This study was essential to confirm that there have indeed been many changes and to plan the next phases of the review. We published the results of the interviews in 2018,” the researcher explains.

The penultimate phase consisted of anesthesia polar bears to take biological samples, mark them with tattoos and fit them with radio transmitter collars. That took them six seasons of field work, between 2015 and 2022 – not to mention 2019 and 2020, when they could not go into the field due to Covid-19. This remote region had been little studied due to its unpredictable climate, steep mountains and heavy snowfall. Some of the collected results were analyzed in the study.

“We will conduct the final part of the research in the coming years. It will consist of using all the data from the collars and the information from the hunters to conduct an aerial count and know how many polar bears That is true,” adds Ugarte.

Genetically different from all others

Another conclusion of the study is that the genetic difference between this group of bears and their nearest genetic neighbor is greater than that observed in any of the 19 populations of bears. polar bonesIt is known before.

“We isolated different types of genetic data from some bears and compared them to other subpopulations around the world. In doing this we find that they are more different from their geographically closest populations than any other pair of populations are from each other.

“It was a really surprising genetic isolation, suggesting a long-term separation,” Beth Shapiro, a molecular biologist at the University of California and director of evolutionary genomics at that institution’s Genomics Institute, tells SINC.

The low genetic diversity of the population also indicates that they have been a small population for as long as they have been isolated. The polar bears In general, they do not have much genetic diversity, but this tends to increase as the population increases.

Isolated population

“We can take advantage of the amount of diversity we see in this population. And how it is distributed among individuals and between population groups to reconstruct its history. In this case we saw that the population was isolated and different from other bears. And it had also been small for at least a few hundred years,” Shapiro points out.

In future studies, they hope to be able to link the fixed genetic differences of this group. That sets them apart from others, with functional adaptations to their unique environment. “For me this is the most important part of the job. There is a population of it polar bears not described above. It does not mix with other populations and is also genetically distinct. It has a different behavior and some different biological parameters,” Ugarte points out.

What they still don’t know is whether the differences with other population groups are due to genes or learned cultural patterns. “More studies will need to be done, but I suspect that what the polar bears They learn from their mothers. And that their own experiences play a very important role in how they adapt to different circumstances,” he continues.

‘Fenced’ polar bears

Researchers believe part of the reason the population is so isolated is that they are surrounded by the jagged mountain peaks and massive Greenland Ice Sheet to the west, the open waters of the Denmark Strait to the east, and the fast-moving East -Greenland Coastal Current. , which poses a danger on the high seas.

He ecosystem Where they live are fjords where the sea only freezes for about four months of the year, but there is ice the rest of the year due to icebergs and chunks of ice coming out of glaciers at the bottom of the fjords, connected to the Greenland Ice Sheet. .

“The recordings we made to place transmitter collars were in April, when the fjords were frozen, so the bears hunted in the usual way looking for seals in the dens where they have their young or in the holes they make in the ice make to breathe. .

And what happens to these polar bears in the summer?

I would like to know how they hunt in the summer. I can imagine that they abuse the pieces of ice where they relax,” Ugarte reveals. But one of the special things they saw is that these bears travel between the fjords, taking shortcuts over the mountains and sliding down the slopes on a kind of slide.

“From the helicopter we could follow their footprints, and then the long trails they left behind as they slid into the snow,” he describes. Satellite tracking of adult females shows that, unlike most others polar bears Because they travel far across the sea ice to hunt, the bears of southeastern Greenland are homely.

In addition, half of the 27 bears tracked accidentally drifted an average of 120 miles (190 kilometers) south on small ice floes caught in the East Greenland coastal current, but then jumped out and walked overland back north to their original fjord.

While this work represents a hopeful vision for the polar bears that could live longer than previously expected in places with glacial ice, these areas are unfortunately sparse compared to their current habitat. “I’m thinking of Greenland, Spitsbergen and parts of the Canadian Arctic,” the scientist adds.

Extrapolation of these findings is therefore not possible because the glacial ice that ensures the survival of the Southeast Greenland bears is unavailable in most of the Arctic. However, it is good news for these bear populations that they have been able to adapt.

In a sense, they offer insight into how the country’s bears might behave in future scenarios, given the currents climate crisis who experiences the world. It will be the Greenland government that will decide on any protection and management measures for these groups.

Likewise, it will be the International Union for the Conservation of Nature, which helps monitor protected species, that will determine whether this is the case polar bears of the Southeast are internationally recognized as a distinct population, the twentieth largest in the world.