Number of the Most Abundant Sea Mammal Species in the Vicinities of the Antarctic Peninsula, Scotia Sea and Powell Basin Area

Abstract

Observations were conducted from the Research Vessel “Akademik Mstislav Keldysh” in the Drake Passage, vicinities of the Antarctic Peninsula, Scotia Sea and the northern part of the Weddel Sea during two voyages in January–early March 2020 (the vessel trip number 79) and during the single voyage in January–February 2022 (trip number 87). Data allow to evaluate the number of the most abundant sea mammals in the area near South Shetland Islands, Scotia Sea and Powell Basin. Observation area of 2022 in the Antarctic were located in about 150 km eastwards of the area of 2020. The area under survey of a little bit greater than 343 th. square km in January-February 2020 held approximately 1200 Humpback Whales (Megaptera novaeangliae) and 2800 Fin Whales (Balaenoptera physalus). In 2022 this area held approximately 2500 Fin Whales and again 1200 or more amount of Humpback Whales. Numbers of the Antarctic Fur Seals in each season here assessed approximately 2000-3000 animals. Type of distribution of these two whale species along the vessel track pointed on the absence of food competition either within or between these species during Antarctic summers of 2020 and 2022. It was possible to evaluate the total numbers of the Antarctic Fur Seal (Arctocephalus gazella), however this evaluation appeared to be less precise than the same ones for Humpback Whales and Fin Whales.