Movement, diving, and haul-out behaviors of juvenile bearded seals in the Bering, Chukchi and Beaufort seas, 2014–2018

Abstract

Bearded seals (Erignathus barbatus) are abundant in the Pacific Arctic and are an important subsistence resource for many Alaska Native communities. The Pacific Arctic is warming rapidly with substantial consequences predicted for ice-associated marine mammals, such as the bearded seal, which led to its 2012 listing as Threatened under the U.S. Endangered Species Act. We provide the most comprehensive description of juvenile bearded seal movement, diving, and haul-out behaviors for the Pacific Arctic, obtained from 24 seals tagged with satellite-linked data recorders along Alaska’s coast from 2014 to 2018. Most seals (19 of 24) made north–south movements with the seasonal extent of sea ice, however, all three seals tagged north of Bering Strait made minimal north–south movements and two seals tagged in the Bering Sea moved north as sea ice advanced south. All seals primarily occupied shallow coastal waters and areas with intermediate-concentration pack ice or that were near the ice edge. Seals spent half their time near the sea floor. Hauling out occurred less in the winter and increased during spring and summer, coinciding with the annual molting period. When ice was at its minimum extent, seven seals frequently hauled out on land. Juvenile bearded seals made use of much of the continental shelf in the Bering, Chukchi and Beaufort Seas, and their use of a broad range of ice concentrations and willingness to haul out on land suggests some resilience to changing sea ice conditions. However, whether the behaviors we documented in juveniles are similar for adult bearded seals remains unclear.