(Erxleben, 1777) - Harp seal
Distinctive Characteristics
The harp seal's head appears somewhat long, wide, and flattened. The long muzzle tapers slightly, and in adults, can appear upturned. The eyes are close-set and there is a slight dip to the forehead. The flippers are relatively small. The foreflippers are slightly pointed and angular, with a short row of digit endings. The claws are strong and dark.
The ontogeny of pelage patterns (reflected in the names of the various age classes) is the species' most distinctive feature. The newborn's pure white coat (which can be stained yellowish for the first few days by amniotic fluid) persists for about 12 days (thus the name “whitecoats”), then it develops a greyish coat (“greycoats”). At about 21 days, the hair begins to fall out in patches (“ragged-jackets”), giving way to a medium grey subadult coat that is scattered with black blotches (“beaters”). At 13 to 14 months of age, “beaters” moult again; the pelage remains the same (“bedlamers”) until the adult pattern begins to appear at the onset of sexual maturity (earlier in males than in females).
The adult pattern is complex and varied. The base colour is silvery white. Two black bands of variable width, joined over the shoulders, extend posteriorly as crescents and sweep down the sides to the area of the pelvis, forming the “harp.” Seen from above, the pattern resembles a large irregular “V.” Black marks may also occur at the insertions of the hindflippers. The head is hooded in black, with a ragged edge on the neck and throat. Many adults retain from a few to many spots; and have incompletely formed harp patterns on their backs (“spotted harps”). A small percentage of seals never develop the harp, retain spots, may have some dark streaks, and are dark grey overall (“sooty harps”).
The dental formula is I 3/2, C 1/1, PC 5/5.
Can be confused with
Harp seals in adult pelage are unlikely to be confused with any other animal. The silvery white body, emblazoned with a conspicuous black harp pattern and hood, is unique. However, the “bedlamer“ and “spotted harp” patterns are more generic, and pose some difficulties. To distinguish harp seals from the 5 other phocids that share their range (harbour, ringed, gray, bearded, and hooded seals), note overall body size; size and shape of the head, muzzle, and nose; details of pelage markings (e.g., spots, rings, or blotches); and base colour (uniform or contrasting from top to bottom).
Size
Adult males are up to 1.9 m in length and average 135 kg in weight, females up to 1.8 m and 120 kg. Pups are born at about 85 cm and almost 10 kg.
Geographical Distribution
Harp seals are widespread in the the Arctic and North Atlantic oceans and adjacent areas from Hudson Bay and Baffin Island east to Cape Chelyuskin, in northern Russia. The most famous of the 3 population centres is the “Front,” near the Magdalen Islands and waters off northeastern Newfoundland and southern Labrador. Harp seals live chiefly in pack ice, but can be found away from it in summer.
Biology and Behaviour
Harp seals congregate to whelp (pup) on pack ice, where they form huge concentrations. Pups are born from late February to mid-March. Mating occurs in the water from mid to late March.
Harp seals are migratory, breeding at the southern edge of the pack ice in late winter, moulting nearby in spring, and following the ice north in summer to the high Arctic. They are very active in the water and sometimes travel in tight groups that are quite large and noisy.
Harp seals feed on a variety of crustaceans and open-water fishes during migration, and switch to several varieties of bottom dwelling fishes in summer on the northern grounds.
Exploitation
Harp seals have been hunted since the earliest times by people inhabiting arctic and subarctic areas. They have been the object of commercial harvesting, principally on the whelping grounds, for fur and oil, dating back to the late 18th Century. In particular, harp seal pups have been clubbed in large numbers for their white coats. This controversial industry continues today on a greatly reduced scale under international quotas.
IUCN Status
Insufficiently known.