Researchers from the Siberian Federal University are observing the migration process of the Taimyr-Evenki reindeer population. The objective of the expedition is to assess the count of young stock born this year in order to make a model for the population dynamics in the changing climate of the Arctic.

During the research, ongoing since 2014 and supported by Rosneft and its subsidiary, East-Siberian Oil and Gas Company, the scientists recorded incremental changes in the reindeer behaviour. Today, reindeer stay on traditional fawning sites at summer pastures of Taimyr for the average of 63 days, which is trice as less as in 1960s. Having barely reached the north end of the Byrranga Mountains, the reindeer turn around and go back, according to the data from satellite trackers. The last decade has seen the herds of reindeer leaving the tundra in mid-August but this time frame is shifted even further back this year. At the average speed of 13 to 14 kilometres per day, the reindeer will have returned to Evenki woods for wintering in August.

The researchers note not only the abnormal decrease in the reindeer’s residence time in Taimyr from 7-8 months to 63 days but also the shortening of their run from 1,100 km to 700 km in the five years of observation. According to estimates, the population count is within 430-450 thousands of animals, while it reached one million in the Soviet times.

One of the probable reasons for such fast-track and massive changes is the so-called greening of the tundra triggered by climate warming. Studies show that the temperature in the polar region is increasing twice as fast as in the rest of the world, which causes the transformation of the vegetation cover on reindeer pastures. The lichen cover shrank from 70% to 17%, while at some places the lichen forage stock dropped 10 times, according to some geobotanical research.

Some researchers mention another reason for the population decline--mass offspring mortality while crossing the northern rivers in spring. While earlier the deer crossed the rivers over ice and passed the greater part of the journey north before the ice drift, now they have to swim across along with the weak fawns many of whom die in water.

To test this hypothesis, SibFU scientists have sent two research groups to the Kheta and the Khatanga rivers area. The expedition should define the sex-age structure of population and the percentage of fawns born in this year (youngs-of-the-year). The collected data will allow making a mathematical forecast of the population size.

SibFU ecologists anticipate that the observed population dynamics can be a response to global climate changes. Reindeer are a sensitive indicator of the state of the Arctic ecosystems so the study of them gives a clue to the Russian Arctic future forecast.

Rosneft
Information Division
July 30,2020

Keywords: Social News 2020