A review of the ecology and status of white whales (Delphinapterus leucas) in Svalbard, Norway

Abstract

The Norwegian Polar Institute initiated a research programme on white whales in 1995 to gather biological information relevant for the species’ management; the results of which are reviewed herein. Satellite tracking from two periods (1995–2001 and 2013–16), between which sea ice diminished markedly, showed that the whales in waters off the archipelago of Svalbard spent most of their time foraging close to tidewater glaciers. Transits between glaciers typically followed the coastline, with the whales moving rapidly from one glacier to another. During the later period, the whales spent some time out in the fjords, suggesting that they might be targeting prey in the Atlantic Water masses that now prevail in Svalbard’s west-coast fjords. Most of their dives were extremely shallow (13 ± 26 m; maximum 350 m) and of short duration (97 ± 123 s; maximum 31.4 min). Fatty-acid analyses indicated that polar cod (Boreogadus saida) was the main prey during the first sampling period. An aerial survey in 2018 estimated the population numbered 549 (CI: 436–723) animals. Svalbard white whales are genetically separate from populations off west Greenland and in the White Sea. Predation by killer whales appears to have influenced white whale behaviour in Svalbard; they are often silent, despite having a normal vocal repertoire for the species and their coastal movements take place in very shallow water. This population has extremely high contaminant levels. Climate change poses a threat to this small population of white whales.

Possible occurrence of contact calls in all‐male groups of free‐ranging beluga whales

“…Wild belugas are known to decrease their vocal activity as an anti‐predator response to nearby killer whales (Fish & Vania, 1971) or during foraging (Alekseeva et al, 2013; Castellote et al, 2021). Predation by killer whales is thought to be an important factor affecting Svalbard belugas' behavior, including their acoustic signalization (Lydersen & Kovacs, 2021). However, because killer whales are extremely rare in the White Sea, a feeding context seems a more likely explanation for the taciturnity of belugas in the Varzuga River.…”

Pathogen Exposure in White Whales (Delphinapterus leucas) in Svalbard, Norway

“…White whales ( n = 27) were live captured in 2001–2006 at various locations in the Svalbard Archipelago ( Table 2 , Figure 1 ); for details see [ 3 , 68 ]. Briefly, the whales were caught in nets that were set from the shore and physically restrained for a short period in shallow water using a rope around the caudal peduncle and a hoop-net held over the head.…”

“…The global population estimate for the species is around 200,000. In the Svalbard Archipelago, white whales are year-round residents that occupy a very tight coastal zone [ 2 , 3 ]. The species is listed in the International Union for Conservation of Nature (IUCN) Red List as “Least Concern” [ 4 ], however, the Svalbard population has been listed as “Endangered” in the Norwegian Red List since 2021 [ 5 ].…”