Bearded Seal
(Erignathus barbatus)
| Distribution and Numbers So named because of their long whiskers, the ice-inhabiting bearded seals are found around the Arctic Ocean and adjacent seas up to a northern limit of 80-85ºN. There are two recognised subspecies of bearded seal. The E. barbatus barbatus subspecies is found in the western Laptev Sea, Barents Sea and north Atlantic Ocean as far south as the Gulf of St. Lawrence in the western Atlantic and Iceland / Norway in the eastern Atlantic, individuals occasionally found wandering as far south as Portugal. The E. barbatus nauticus subspecies inhabits the remainder of the Arctic Ocean, as well as the Bering and Okhotsk Seas, being found as far south as Hokkaido and, very occasionally, China. There is currently no up-to-date overall population estimate for bearded seals. Estimates have been made of 300,000 for E. barbatus barbatus in the early 1970s, and of 250,000 - 300,000 for E. barbatus nauticus in the early 1980s. |
 Photo: B. Christman, National Marine Mammal Laboratory |
| Status Changes in the abundance of bearded seal populations have not been reported. The effects of natural events and human-caused activities on the abundance of bearded seals are however difficult to determine due to the lack of accurate population data and the difficulty of counting the species. The bearded seal is listed as an Appendix III species under the Bern Convention. |
| The biggest concern at the moment is probably the effects that changes in the Arctic climate may be having on the bearded seal's environment, both through changes in water flow and the transport of nutrients through the Bering Strait, and also the loss of ice habitat caused by such factors as global warming. In addition there are concerns that oil and gas exploration and extraction in many parts of the species' range, particularly in the Chukchi and Beaufort Seas, may cause disturbance to bearded seals as well as possible pollution of the seals, their habitat and their food supply. Potential pollution and disturbance from vessel traffic on the proposed Northern Sea Route is also a cause for concern. There is a potential for conflict between bearded seals and commercial fisheries, particularly in the central Bering Sea for species such as clams, tanner crabs and large snails / whelks, all components of the bearded seal diet. |
 Photo: Kathy Frost, Alaska Department of Fish and Game |
The bearded seal has long been subjected to hunting by
Arctic coastal communities for food, clothing and other subsistence purposes. In previous
years up to 1,500-2,000 seals have been killed each year by Russian hunters in the Bering
and Okhotsk Seas. The current scale of this hunt is likely much lower, although accurate
figures are not available. Bearded seals are also hunted by Alaskan natives but there are no reliable up-to-date figures on the extent of this hunting. Partial data for the 1990s (Norton Sound region and Kotzebue Sound region) indicate an annual kill of about 1,750 seals. However this does not include other areas where bearded seals are an important component of the diet. Local hunting also takes place in Canada and Iceland, while the hunts in Norwegian Svalbard and Greenland take about 100 and 500-1,000 seals per year respectively. These figures do not include seals that are lost during hunting because they sink when killed and cannot be retrieved. |
| Lifestyle The coat of the bearded seal is generally grey to brown and unpatterned. The seal has a noticeably small head in relation to its large size, square-shaped foreflippers and, unusually for a member of the Phocidae, four rather than two teats. |
| Bearded seals are solitary and are mostly found in seasonally ice-covered waters less than 200m deep. They prefer to inhabit areas of broken pack ice and drifting ice floes, but are quite versatile and also occur in areas of shorefast ice and thick ice where they are able to maintain breathing holes. Many of the seals move long distances to follow the receding ice in the summer. They are known, for example, to move from the White and Kara Seas to the northern Barents Sea and from the Bering Sea to the Chukchi Sea. In other areas such as the Laptev, Okhotsk and White Seas they do not follow the ice, but spend the summer in open water, sometimes hauling out on land, preferably on gravel beaches. Bearded seals have also been reported as hauling out and swimming in rivers that empty into Hudson Bay in Canada. Young bearded seals in Alaska may be found in open water, not associated with ice, in summer and autumn. When hauled out on an ice floe, bearded seals are characteristically seen at the edge of the floe with their head pointing towards the water and downwind. From such a position they can move rapidly into the water, probably important as a protection against predators. |
| Pupping and moulting take place on the ice. Most pups are born from mid-March to early May, later in the north than in the south. Pups are born with a greyish-brown coat, lighter patches on the face, head and back, having shed their white pre-natal coat in the womb. Bearded seal pups can swim very shortly after they are born, and at less than a week old have been recorded diving for more than 5 minutes to as deep as 75m. This early development of aquatic ability may have evolved as a means of escaping polar bears. The pup is nursed for about 18-24 days, putting on weight very quickly, and moults into its adult coat at about the time it is weaned. It is believed that the mother also mates around this time. The adult male has a very audible and musical underwater call during the breeding period and it is thought that this call is a means of signalling his underwater territory and/or his breeding condition. Moulting usually takes place in May and June, the seals' peak haulout period, although reports from Inuit in some areas suggest that the moult is variable in timing, some saying that it occurs at any time of the year. |
| Bearded seal diet is varied but consists mainly of decapod crustaceans
(such as shrimps and crabs), and molluscs (such as clams and whelks). Some fish species
such as sculpin, flatfish and cod are also eaten. Bearded seals prefer to feed at the
bottom in areas with water depths of less than 130m. They are preyed upon by polar bears
and killer whales. Walruses are also known to eat an occasional bearded seal pup. |
| Statistics Adult bearded seals of both sexes measure 2.1-2.4m and weigh 200-250kg (maximum 360kg). In some regions, females appear to be slightly larger and heavier than males. Pups are on average 1.3m long and 34kg in weight at birth. Females reach sexual maturity at 3-8 years, males at 6-7 years. Few bearded seals are found to live longer than 25 years, but one female was found to be 31 years old. It is possible that the age of mature bearded seals may be underestimated due to the natural wearing away of their teeth, and that individuals perhaps live longer than has been measured. |
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