Arctic: The polar bears resist, until when?

Eternal pollutants, cast iron of the ice floe: the polar bears of the Svalbard in the Arctic manage to face the ravages of man on the planet better than expected, have noted experts from the Norwegian polar institute (NPI), but for how long?

“So far, they seem to go well. There are notable changes in their behavior, but they remain in good health and in good physical condition, they reproduce, they are better than we fear. But there is a limit and the future may not be so radiant, “summarizes Norwegian Jon Aars, head of the” polar bear “program at the NPI. He bases his observation on the study of 50 to 70 polar bear captured each year over two decades.

For forty years, the NPI has observed this mammal in Svalbard, where it is affected both by the “eternal pollutants” produced at the end of the world and by global warming three to four times more important in the Arctic than the world average. About 300 polar bears live in Svalbard all year round, according to the polar institute.

In April, eight scientists participated in an expedition to the Kronprins Haakon research break, during which new methodologies were experienced. Experts have for the first time took slices of fatty tissue where PFAS are housed to assess their impact on the bear health.

They also noted the data from cardiac sensors implanted last year on females and which, coupled with GPS, must give information on their energy expenses according to a new technology.

Between two outings, they expressed their observation to an AFP photographer who accompanied them for this mission. “Over the years, there have been bears that we have repeatedly recapped, sometimes six or eight times, and we have observed a decrease in pollutant levels in some of them. This reflects the success of the regulations in recent decades, “notes the Finnish eco -with Heli Routti who has been working on this program for 15 years.

NPI experts contribute to the Arctic Surveillance and Assessment Program (AMAP), under the leadership of the Arctic Council, whose conclusions are taken into account for the adoption of regulations against different types of pollutants.

“The concentration of many pollutants, subject to regulations, has decreased in forty years in the water of the Arctic. But the variety of pollutants has increased. We now observe more types of chemical substances, ”continues Heli Routti, evoking prohibited organochlorine pesticides, but found in adipose tissues or perfluored compounds identified in the blood of the mammal.

Almost indestructible and present in quantity of objects and products such as non-stick stoves or cosmetics, “eternal pollutants” are per- and polyfluoroalkylated chemicals that accumulate in the air, soil, water, food and, ultimately, in the human body, especially in the blood and the kidney tissues. These PFAS worries for several toxic health effects, including cancers for some.

Regarding global warming, “what we can clearly see is that the environment changes, the ice floe backs. Bear can no longer use it as 20 or 30 years ago. There is also a significant inter-annual variability: from one year to the next, the conditions change a lot, which makes the environment more and more unpredictable. It is difficult to follow for animals, ”explains the Frenchman Marie-Anne Blanchet, specialist in space ecology.

“But bears have an advantage: they live for a long time, accumulate experience and learn throughout their lives. This gives them some adaptation potential. For example, in recent years, the local Svalbard bears have started chasing more Rennes, ”continues Marie-Anne Blanchet.

“Is it because the population of Rennes increases?” Or because they can no longer catch seals because of the decline in ice? Difficult to say. But this food diversification can help them adapt. ” As long as we do not reach a rocking point “beyond which the bears could no longer face the changes,” she adds.

The Norwegian Polar Institute (Norsk Polarinstittt), based in Tromso, is a public organization responsible for scientific research and the management of polar zones. It is mainly funded by the Norwegian State with supplements from national and international projects.