White whale4/18/2023 ![]() In Svalbard their diet appears to be dominated by polar cod with capelin and shrimps also being consumed. In western Greenland white whales consume pelagic polar cod and arctic cod. In summer they often feed on seasonally abundant anadromous (salmonids) and coastal fishes in some parts of their range. White whales consume a wide variety of prey items ranging from benthic invertebrates and squid to pelagic fishes. White whales are quite slow swimmers but they can dive to depths greater than 1,000 metres, though in the Barents Sea Region water depths limit their diving to a few hundred metres. Similar to other toothed whales, white whales use echolocation during foraging and probably also when travelling in murky water to avoid striking objects. In Svalbard white whales spend a lot of their time along tidal glacier fronts, during the ice-free season, presumably because up-welling in these areas result in concentrations of prey being available. White whales usually feed in waters above the continental shelf, often at discrete coastal locations at least during the summer months. During the early winter they have been documented travelling deep into drifting ice where the ice cover was more than 90%.ĭifferent foraging strategies might play a role in the different movement patterns observed across the species range. In Svalbard, white whales remain very close to the coasts. Although the winter whereabouts of white whales are poorly known, it is assumed that they either over winter in polynyas and ice leads or they migrate in the direction of the advancing polar ice. In some regions white whales tend to follow the seasonal movement patterns of the sea ice, remaining near the expanding or retracting ice edges. In some regions they spend a lot of time in coastal areas, occasionally even in estuarine areas, during summer – while in other areas they occur far offshore. In some areas they exhibit marked migratory patterns, while in other areas they remain resident year round. Beyond this basic knowledge, the social dynamics of this species are not well documented.Īcross their range, white whales display highly variable patterns with regard to seasonal movements. Groups are not fixed entities, they seem to divide and reconsolidate through time. There is significant sexual segregation among groups of white whales with females, calves and juveniles travelling together, while adult males form separate groups. However, in Svalbard white whales are remarkably quiet for unknown reasons. Most populations are extremely vocal – which has given this species the popular name canaries of the sea. White whales are very social animals that travel in groups virtually all the time. The number of white whales is Svalbard is not known, but they are the most numerous cetacean species in the area and also the most commonly observed whale. The global population of white whales is not accurately known, but adding the numbers from all of the various stocks results in a figure of about 200,000 animals. During their moult white whales shed an outer cork layer as well as the top layers of skin this special ”cork” is unique to white whales and the closely related narwhal it thought to be an adaptation to protect the skin from ice-abrasion. White whales can appear a rusty yellow prior to their annual moult during the summer. Females are white by about age 14, whereas males are about 20 when they are completely white. They fade in colour over their juvenile years becoming lighter each year until they are eventually white. They are approximately 140 cm long and weigh 50–60 kg. When white whales are born they are creamy-grey in colour, but turn dark grey rapidly. They have small flippers and a small fluke. ![]() They have small eyes, a bulbous melon on the front of their heads, and a flexible neck (unlike most cetaceans that have fused neck vertebrae). White whales lack a dorsal fin but they have a prominent dorsal ridge that is used to break through thin ice. Females are somewhat smaller reaching 4 metres and 1,200 kg. Males reach lengths of 4.5 metres and 1,500 kg. ![]() White whales are a mid-sized toothed whale ( Odontocete). International cooperation in the Arctic.International cooperation in Antarctica. ![]()
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