Late summer distribution and abundance of ice-associated whales in the Norwegian High Arctic

Endangered species research

Tiago A. Marques^2,3¹  Christian Lydersen^1²  Jon Aars^1³  Heidi Ahonen^1⁴  Jade Vacquié-Garcia^1⁵ 

[1] Environmental Modelling (Scottish Oceans Institute), Buchanan Gardens, St Andrews, KY16 9LY, UK^2;Centre for Research into Ecological &Centro de Estatística e Aplicações da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal^3;Institute of Marine Research, 5817 Bergen, Norway^4;Norwegian Polar Institute, Fram Centre, 9296 Tromsø, Norway^1

关键词: Abundance;    Arctic;    Belugas;    Bowhead whales;    Climate change;    Distribution;     ;    Narwhals;    Svalbard;    White whales;   

DOI  :  10.3354/esr00791

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

The Arctic is experiencing rapid warming, and resultant sea ice losses represent a serious threat to ice-associated species in the region. This study explored the distribution and abundance of the 3 Arctic resident whale species: narwhals, bowhead and white whales, in the marginal ice zone and into the sea ice north of the Svalbard Archipelago. Line-transect surveys were conducted using a combination of helicopter-based and ship-based efforts in August 2015. Twenty-six sightings, involving 27 bowhead whales and 58 narwhals, occurred along the helicopter transects, while no whales were recorded along ship transects. No white whales were observed during these surveys. After correcting for surface availability, distance sampling produced abundance estimates of 343 (CV = 0.488) bowhead whales and 837 (CV = 0.501) narwhals within the 52919 km2 study area. Bowhead whales were predominantly seen close to the ice-edge, whereas narwhals were located deeper into the ice. To contextualize these results within the broader Svalbard cetacean community, all whale sightings from the Norwegian Polar Institute’s Svalbard Marine Mammal Sighting Data Base, from the period of the survey, were mapped to compare general distributions. These opportunistic sightings included numerous cetacean species, especially seasonally occurring ones. However, white whales dominated in terms of the numbers of individuals reported. Our results suggest little spatial overlap between seasonally occurring whales and the 3 Arctic resident whales. Bowhead whales and narwhals were tightly associated with sea ice, and white whales were tightly coastal. In contrast, the seasonally occurring species were found over the shelf and along its edges.

【 授权许可】

Unknown