Seasonal Movements and Relative Abundance of Bearded Seals (<i>Erignathus barbatus</i>) in the Coastal Waters of the Chukotka Peninsula

Abstract

Information about bearded seal seasonal distribution in the Pacific Arctic is limited. Bearded seals (Erignathus barbatus Exleben, 1777) from coastal sites along the southern, eastern, and northern Chukotka Peninsula, Russian Federation, were observed most seasons during 1993 – 96, 1998 – 2000, 2002 – 05, and 2010 – 11. These observations provide spatial and temporal information about bearded seal seasonal distribution, movements, and relative numbers in the coastal zones. In winter, bearded seals aggregate on the young ice in the northern part of the Gulf of Anadyr. Numbers gradually increase during March. In springtime (April–May), bearded seals in the northern Gulf of Anadyr are relatively numerous around Nunligran (Cape Achen), but the number is highly variable across years. During spring bearded seals move eastward along the coast from the northern part of the Gulf of Anadyr towards the Bering Strait and then to the north, as the marginal ice edge zone retreats north. These movements to the east and north continue in ice-free water, and by August, the spring migration of bearded seals along the coast of the Chukotka Peninsula ends. In the summer months of August and September, few bearded seals are present in this coastal zone. The southward autumn migration of bearded seals is not evident near the coast, which suggests that it occurs farther from shore.

Seasonal variations in the call presence of bearded seals in relation to sea ice in the southern Chukchi Sea

“…Of these, E. b. nauticus shows seasonal north-south migration pattern relating to sea ice extent. During spring breeding season, they extend the Beaufort, Chukchi, and Bering Seas (Burns 1981), and most of seals in the Bering and southern Chukchi Seas move northward as sea ice retreat during July and little seals remain in August (McClintock et al 2017;Melnikov 2017). On the other hand, the southward autumn migration pattern is not clear.…”

Seasonal sea ice dynamics drive movement and migration of juvenile bearded seals Erignathus barbatus

“…Previous treatments of bearded seal movement were descriptive and mostly based on sightings near shore, from cruises near the spring ice front, and a few aerial surveys of limited temporal and spatial scope (Burns 1981, Kelly 1988, Cameron et al 2010, Conn et al 2014, Ver Hoef et al 2014, Melnikov 2017. Few analyses of bearded seal tracking data have been published.…”