May 28, 2023

Polar bears are one of the largest land predators on the planet, listed in the International Red Book and the Red Book of the Russian Federation. What else is interesting and unique about these inhabitants of the Arctic? How does their proximity to humans affect them, why have they been visiting residential areas more and more often lately, and how does this way of life affect animals? We talked about this with Ilya Mordvintsev, a leading researcher at the Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, who studies polar bears as part of the Russian Geographical Society’s grant project “Study of rare animal species.”

— How long have you been studying polar bears during expeditions of the Russian Geographical Society and what are the results of this work?

Our research with the support of the Russian Geographical Society began in 2010 and continues to this day. The first expedition took place on the island of Alexandra Land of the Franz Josef Land archipelago, which is the territory of the Russian Arctic National Park. One of the tasks that confronted us at the first stage of research was to find out which methods of trapping polar bears in different seasons of the year can be used with less harm to them. We analyzed hormone levels of stress when trapping animals, baiting, using ground vehicles, an all-terrain vehicle or snowmobile, and from a helicopter. The animal traps were ruled out almost immediately. The bear, being in a confined space, experiences a lot of stress – the greatest in comparison with other methods. Pursuit using a snowmobile, an all-terrain vehicle, a helicopter is also not a very suitable option. The most benign were the baits. In a closed place, for example in an abandoned building, a group of researchers sits in anticipation and, as soon as the animal approaches the bait, immobilizes it.

We obtained interesting results during the expedition of the Russian Geographical Society on the islands of Bely, Vilkitsky and Shokalsky in the Kara Sea near Yamal. There, the main focus of work was to study the adaptation of polar bears to being on land during the ice-free period. It turned out that every year the number of polar bears remaining on the islands in these places is increasing. This is due to climate change: due to the earlier melting of sea ice, animals do not have time to leave for drifting ice.

– It is known that the male kills cubs not always because of hunger, but when the female soon becomes ready for mating. Is he guided by the mind or instinct?

The polar bear is a curious, but at the same time extremely cautious and very intelligent animal that learns well and adapts to various situations. As for the case of an attack on cubs, this is a purely instinctive behavior of the animal. In general, how to evaluate the mind? For example, a bear sits at the base of a huge iceberg that has broken off a glacier and is frozen into the sea ice. We notice him, we decide to immobilize him. So he does not run on ice, on which we can catch up with him, but climbs to the top of the iceberg, realizing that we cannot get there. Or we fly in a helicopter. Not far from the glacier with a sheer wall about 30 m high, we notice a bear. When we start to pursue him, he does not run away from us anywhere, but runs up to the wall of the glacier and stands, realizing that we will not be able to descend by helicopter below and get him. Is it mind or instinct? Still, this is a choice of a smart strategy of behavior.

— You studied polar bears in Novaya Zemlya. And those of them that are looking for food near human habitation, have also become the subject of your research?

On Novaya Zemlya there is a large MSW (municipal solid waste) landfill. Sometimes up to 60 individuals gather on it, creating quite serious problems for the residents of the village. We studied the behavior of more than 20 bears, observed the movement of 10 females and came to disappointing conclusions. According to our observations, the bears that fed on the landfill, at least the individuals we marked, did not go north along with the ice, as, in theory, they should have behaved, but went back to the island and returned to the landfill to feed on the remains human food. There is a clear change in the natural behavior of these animals.

How does this affect their physical well-being?

We compared the microbiome of bears in their natural habitat and those who remain on the island. The microbiome of the animals present in the landfill was significantly different. If the fauna that inhabits the body of a bear in the natural environment is known to some extent, then we observe the presence of microbiome communities that are unusual for a polar bear as a species. Cases of registration of new pathogens in bears are also increasing. The increase in cases of canine distemper virus is recorded mainly in areas where animals more often intersect with humans. This dangerous disease can be carried by pets, their waste products can be in a landfill.

– If the landfill is removed, can polar bears return to their usual way of life?

Of course, they have nowhere to go, and they will return to their natural habitat. But, having tasted human food, the polar bear, moving through the expanses of the Arctic, at the first opportunity, sensing the proximity of human habitation, will strive for it in order to find food near people. This leads to an increase in conflict situations with a person.

– You followed the movement of females – why only them?

We catch and study adult animals of both sexes, but the collar with a satellite transmitter can only be put on a female, her neck girth is smaller than her head girth. The male has the opposite, so the collar falls off him. And most importantly, in males, when the body accumulates fat during the period of active hunting, it is rapidly deposited in the cervical region, so the collar can harm the animal by squeezing the neck. The male can attach a mark to the coat, but such a transmitter does not work for long. If we can follow a female with a satellite collar for one and a half to two years, then a male with a tag can be monitored for a maximum of one and a half to two months.

– It is known that the female predator seeks not only to protect and feed the cubs, but also to teach them to hunt and survive. What do female cubs learn when they forage near human habitation?

The female polar bear trains cubs up to the age of two. These cubs will not say that they are absolutely not adapted to hunting seals in their future life, it is difficult to say this on the basis of only two years of observations, but they are used to what is uncharacteristic for them in their natural habitat. For example, to live in such a “kindergarten”. It is often difficult to understand which bear cub belongs to which mother, there are so many of them, and they coexist in a heap. I would say that this is already an inferior animal, which, following its mother, got used to easy prey in ice-free periods. Of course, the percentage of tagged animals in relation to the entire group that we observed there is insignificant, so I cannot make an unambiguous conclusion that all such females, leaving for the ice, will definitely return to this food spot.

— That is, coexistence next to a person is impossible without harm to polar bears?

On the Alexandra Land of the Franz Josef Land archipelago, the presence of people is growing every year. But human activity there is carried out quite neatly. We did not see a decrease in the number of meetings of animals on the island at different times of the year, a significant change in behavior, and also in the state of health according to the analysis of samples collected from bears in 2022 compared to 2010, although these animals coexist to some extent with people. In 2021, we worked in the southern part of this archipelago and watched bears on the ice, that is, those who are in their natural habitat hunting seals. They caught them, took samples from them and obtained the same data from them as from bears on Alexandra Land. It can be said that in this region, controlled anthropogenic influence occurs without harm to polar bears.

– Are there any habitats of polar bears that are not at all subject to anthropomorphic influence?

On the archipelago of the Bear Islands, where the reserve of the same name was created in 2020, there is no person at all. Together with his staff, we conducted research during the expedition with the support of the Russian Geographical Society in 2022. Bears enter the islands from the ice and remain on them in large numbers when the ice breaks. And they are all in good condition: 4-5 points on the fatness scale. Why individuals in the ice-free period are in such good condition remains to be seen. Bear Islands can be called another “maternity hospital” for polar bears (in addition to Wrangel Island and the Franz Josef Land archipelago), the number of birth dens registered by the reserve’s staff is growing every year. What is the dynamics of change – this and many other questions have yet to be answered.

In 2022, the Umka-2022 complex expedition took place, organized by the Russian Geographical Society together with the High Command of the Navy with the participation of Roszapovedtsentr and the Ecofactor company. One of its key tasks was the “Polar bear census” – monitoring polar bears on Wrangel Island using drones. They took more than 22,000 photographs, including 512 photo portraits of polar bears, fixing the time and coordinates of the meeting with each animal. In total, scientists counted 864 polar bears on Wrangel Island.

— The results of the expedition are unprecedented! — Ilya Chernook, Development Director of ANO Ecofactor, said. “There has never been such a number of digitally documented polar bears in the history of research on this animal. All the stars converged on this expedition: the use of innovative technologies, the organization of the expedition by the Ministry of Natural Resources, the participation of highly qualified specialists from the Wrangel Island Reserve, and, of course, the assistance and support of the Russian Geographical Society. We plan to continue research this year together with the professional team of the Russian Geographical Society.

In the future, specialists plan to expand the survey area to the entire Wrangel Island, count the number of polar bears on Herald Island and in the 12-mile zone of the sea, explore the Bear Islands and then gradually move further west, examining the entire Arctic zone of Russia step by step.

Marina Kruglyakova

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