The ringed seal is the most common seal in the Arctic. This species is rarely found on the open sea, but instead is prefers areas where the ice is firm. It is found along Pacific Japanese coasts, the northern parts of the Baltic Sea, Canada, Alaska, and Siberia (Harris 1991).
The preferred habitat of P. hispida is areas that freeze to stable ice in winter (Kingsley 1990). This species lives in darkness under ice for several months during the year (Hyvarinen 1988). Ringed seals make lairs in the snow and ice for protection from predators and thermal shelter. They can occupy ice covered areas by maintaining breathing holes and breathing through cracks in the ice. Ringed seals make their lairs by rubbing away the ice with their fore flippers (Smith and Stirling 1975).
Adult ringed seals are 140-150 cm in length, and females are generally slightly smaller than males. Pusa hispida is similar in shape and color to common seals, but it is generally darker. The belly is silver gray color and the dorsal side is pale gray with dark spots that are surrounded with pale colored rings (Harris 1991).
Males are thought to be polygynous and probably hold underwater territories.
The female ringed seal matures reproductively at about 6 years of age and may bear one pup per year (Kingsley 1990). Most mating occurs in late April and early May, which is within one month of parturition (Frost and Lowry 1981). Although mating occurs in May, the blastocyst does not implant until August or September. The gestation period is approximately 240 days (Kingsley 1990). Ringed seals require solid ice for pupping, which makes the pups more vulnerable to predators.
Adult seals are solitary except for loose feeding aggregations in the water in summer. Starting in mid-May, ringed seals haul out onto the ice and bask in the sun. They moult at this time and do not feed very much (Kingsley 1990). Groups of seals at haul out sites are large and seals lying on the ice are vigilant and aggressive.
Ringed seals spend most of their time feeding from late summer to early spring (Frost and Lowry 1981). During the spring and summer, Pusa hispida feeds on saffron cod (Eleginus gracilis), various shrimps, hypeni amphipods, and euphausiids. In the fall, Pusa hispida eats mostly saffron cod, and from winter to early spring, ringed seals feed mainly on Arctic cod (Boreogadus saida) (Lowry et al. 1980).
Ringed seals are preyed on by humans and polar bears in the Arctic. Pups are taken by bears, foxes, and humans when they are in the birth lair (Hammill and Smith 1991). As a result of strong predation, ringed seal pups spend a large proportion of time in the water and learn to dive at an extremely young age (Lydersen and Hammill 1993).
Pusa hispida is an important source of food for humans, dogs, foxes, and polar bears in the Arctic.
The ringed seal is also used by Inuit for fuel and clothing (Kingsley 1990). Newly moulted ringed seal pups are hunted by Canadian fur traders for their pelts (Frost and Lowry 1981).
Pusa hispida is a very common species and, as of now, there are no measures to protect it The habitat is protected as it is the same habitat as the polar bear (Ursus maritimus). The ringed seal is an important part of the polar bear's diet (Kingsley 1990).
Cindy Felcher (author), University of Michigan-Ann Arbor.
the body of water between Europe, Asia, and North America which occurs mostly north of the Arctic circle.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
the nearshore aquatic habitats near a coast, or shoreline.
in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
A substance that provides both nutrients and energy to a living thing.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
specialized for swimming
the area in which the animal is naturally found, the region in which it is endemic.
an animal that mainly eats fish
the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.
having more than one female as a mate at one time
mainly lives in oceans, seas, or other bodies of salt water.
breeding is confined to a particular season
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
young are relatively well-developed when born
Frost, K.J. and L.F. Lowry. 1981. Ringed, Baikal and Caspian seals - Phoca hispida Schreber, 1775 Phoca Sibirica Gmelin, 1758 Phoca caspica Gmelin, 1788. Handbook of marine mammals. Academic Press, New York.
Harris, S.H. 1991. The handbook of British mammals. Blackwell Scientific Publications Ltd., Osney Mead, Oxford. p. 480.
Hammill, M.O. and T.G. Smith. 1991. The role of predation in the ecology of the ringed seal in Barrow Strait, Northwest Territories, Canada. Marine Mammal Science, 7(2): 123-135.
Hyvarinen, H. 1989. Diving in darkness: whiskers as sense organs of the ringed seal (Phoca hispida saimensis). Journal of Zoology (London), 218(4): 663-678.
Kingsley, M.C.S. 1990. Status of the ringed seal, Phoca hispida, in Canada. Canadian Field-Naturalist, 104(1): 138-145.
Lowry, L.F., K.J. Frost, and J.J. Burns. 1980. Variability in the diet of ringed seals, Phoca hispida, in Alaska. Canadian Journal of Fish and Aquatic Sciences, 37(12): 2254-2261.
Lyderson, C. and M.O. Hammill. 1993. Diving in ringed seal (Phoca hispida) pups during the nursing period. Canadian Journal of Zoology, 71(5): 991-996.
Smith, T.G. and I. Stirling. 1975. The breeding habitat of the ringed seal (Phoca hispida): The birth lair and associated structures. Canadian Journal of Zoology, 53(9): 1297-1305.