The scientists' work included daily accounting of the number of animals on the shore and in the water area, an assessment of the sexual and age structure, as well as an analysis of the factors of anxiety and mortality of walruses on shore rookeries. The key to the rapid collection of information was the use of unmanned aerial vehicles.
According to experts of the Pacific branch of VNIRO, the first walruses were spotted at Cape Heart-Stone in the Chukchi Sea on September 17 last year. The peak number was noted on October 23, when there were more than 64 thousand individuals on the shore, mature females dominated the rookery.
Due to warming in the eastern Arctic, scientists believe that storms in the Chukchi Sea have become more frequent during the summer and autumn season. There is a late ice formation - this affects walruses, it is more difficult for them to get food. The duration of migration through open water has increased, the animals come ashore weakened and exhausted. The lack of ice forces polar bears to stay on the shore, which increases the number of factors of concern for walruses. As a result, the mortality of walruses in rookeries increases.
In general, taking into account the data of 2020 and a long-term series of previous observations, scientists have concluded that the state of the Pacific walrus population in the Arctic Seas surrounding the Chukchi Peninsula is in satisfactory condition. The replenishment of the sexually mature part of the population is at the level of the average long-term indicators.
The occurrence of whales in the Mechigmen Bay increased slightly. According to scientists, this is due to a good food supply in the area.
Studies were also conducted on the number of largs in the Anadyr estuary. The maximum number of animals was noted on July 31 last year, and amounted to 637 mammals – this is 200 animals more than in 2020. Larga is the main consumer of Pacific salmon going through the Anadyr Estuary to spawn.
According to Kirill Kolonchin, Director of VNIRO, in 2022 scientists will continue monitoring the coastal rookeries of the Pacific walrus and larga, as well as whale watching in the Mechigmen Bay.
"The effectiveness of our work in this direction largely depends on the technical base of the research. Now we are actively developing and improving the practice of using unmanned aerial vehicles, which allows us to obtain more accurate data for estimating the number of walruses due to their fixation on hard-to-reach areas of the coastline," the director of the Institute stressed.
VNIRO scientists express their gratitude to the residents of national villages for their active assistance to scientific observers during research work.
VNIRO Press Service