Ringed seal (Pusa hispida)
|Also known as:||Arctic ringed seal, Baltic ringed seal, fjord seal, jar seal, Ladoga seal, Okhotsk ringed seal, Saimaa seal|
|Size||Average length: up to 1.30 m (2)|
|Weight||50 - 110 kg (3)|
The ringed seal is classified as Least Concern (LC) on the IUCN Red List (1).
The smallest of all living seal species, growing to a maximum length of just over 1.5 metres (4), the ringed seal (Pusa hispida) is named for the conspicuous ring-shaped markings on its coat. Dark grey spots are encircled by light greyish-white or silver rings, which are most obvious on the back and sides and often so dense that the marks fuse. The coat is variable in colour, but it is usually dark grey on the upperparts and light grey to silver on the underparts (5) (6).
The ringed seal is notably plump with a small, rounded head and a short, thick neck. The broad, blunt muzzle and large, close-set, forward-facing eyes impart an almost cat-like appearance (5). The fore-flippers are relatively small and slightly pointed, bearing claws more than one inch thick that are used to maintain breathing holes through thick ice (6). The vibrissae (whiskers) are light-coloured and beaded (5). The male ringed seal tends to be slightly larger than the female (2).
The ringed seal pup is born with woolly, thick, whitish fur known as ‘lanugo’. As the pup grows, the fur becomes finer and slightly longer than that of the adult, and is dark grey on the upperparts, fading to silver on the underparts. At this stage the pups are known as ‘silver jars’. The pup may also have a scattering of dark spots on the underparts and a few rings on the back (5).
The ringed seal has a circumpolar distribution around the Arctic, occurring in northern parts of the Baltic Sea, Canada, Alaska, Siberia and along the Japanese Pacific coastline.
There are five subspecies currently recognised. The Arctic ringed sea (Pusa hispida hispida) is perhaps the most common of all seals in the Arctic region, occurring in all of the Arctic Ocean seas, as well as the Bering Sea, ranging as far south as Newfoundland and northern Norway. The Okhotsk ringed seal (Pusa hispida ochotensis) is found in the Okhotsk Sea and northern Japan, while the Baltic ringed seal (Pusa hispida botnica) inhabits the northern and central Baltic Sea, with most seals residing in Bothnian Bay. The Ladoga seal (Pusa hispida ladogensis) is found only in Lake Ladoga in western Russia, while the Saimaa seal (Pusa hispida saimensis) occurs only in Lake Saimaa in eastern Finland (1) (7).
The ringed seal is regarded as an ice-associated species, as it uses ice all year round. Its ability to create and maintain breathing holes in sea ice, using the well-developed claws on their fore-flippers, allows it to thrive in areas where other seals cannot reside. Adult ringed seals excavate lairs or dens on the surface of sea ice for birthing and rearing young, as well as for protection from predators and the extreme cold (1) (4).
The Arctic and Okhotsk ringed seals use sea ice exclusively as their breeding, moulting and resting habitat, rarely coming onto land. The Baltic ringed seal and the Ladoga and Saimaa seals, which both occur in freshwater, also use ice for breeding and moulting, but are forced to haul out on islands and shorelines during the summer, when ice is not available (1).
Some ringed seals migrate on a seasonal basis in response to ice availability and there is evidence of long-distance migration, particularly for juvenile ringed seals (8).
Superbly adapted to life on stable Arctic sea ice, nearly all ringed seals breed on fast ice (ice that has frozen along coasts and extends out to sea), where the female excavates lairs in which to give birth (9). The lairs provide thermal protection against cold air temperatures and high wind chill and afford at least some protection from predators, such as Arctic foxes (Vulpes lagopus) and polar bears (Ursus maritimus) (1). The females give birth to a single pup between March and May, with most pups born in early April, although in Lake Saimaa and in the southern part of the Baltic Sea pups are born earlier, in late February or early March (1). The female moves the pup between a system of usually four to six lairs, to prevent the pup being located by predators. However, ringed seal pups learn to dive when they are very young and are soon able to move between lairs independently (1). The female lactates for about six weeks after birth, when both the mother and the pup are active, and spends considerable time making short feeding dives. The pups are weaned prior to the spring ice breakup in June (4). Mating takes place around one month after birthing, but the embryo does not implant in the womb until August or September. The gestation period lasts for around 240 days (8).
After breeding, the ringed seal hauls out on ice at the edge of permanent pack ice to moult. This usually occurs between mid-May to mid-July, during which time the ringed seal rarely feeds and tends to lose much body weight. Female ringed seals reach sexual maturity at three to seven years of age, while males reach sexual maturity at five to seven years, although they probably do not participate in breeding before they are eight to ten years old (1). Male ringed seals are likely to be polygynous, meaning they mate with more than one female. They probably also establish underwater territories during the breeding season (8).
The ringed seal is a fairly opportunistic predator that consumes a variety of fish and crustacean prey. Adult ringed seals tend to prefer to forage on small schooling fish species, but invertebrates such as krill and shrimp may form a more important part of their diet depending upon location and season (1) (4). Polar bears are the ringed seal’s most important predator, with pups and immature seals being particularly vulnerable to predation. Other ringed seal predators include walrus (Odobenus rosmarus), killer whales (Orcinus orca), Arctic foxes, gulls and ravens (4).
The ringed seal has been a mainstay in the diet of native Arctic peoples. Its meat is consumed by people and fed to sled dogs, while its skin is used for clothing. This subsistence hunting continues at unknown levels to this day, but many tens of thousands of seals are thought to be killed each year (3). Commercial hunting has also been widespread. Harvesting for the ringed seal’s pelt peaked in the mid-20th century, when it caused localised declines at southern latitudes, including in the Baltic and Okhotsk Seas. However, harvesting pressure on the ringed seal is now thought to be much less significant (1).
Other threats to the ringed seal include pollution, entanglement in fishing nets and disturbance (1) (2) (3). Pollution is a particularly significant threat in the Baltic Sea, as well as in Lake Saimaa, where mercury pollution from lake-side developments is thought to be contributing to poor breeding success and an ongoing population decline of the Saimaa seal (8). Between 200 and 400 Ladoga seals are thought to die each year as a result of entanglement in fishing nets (8).
However, the greatest threat to the ringed seal is climate change. The ringed seal is dependant upon ice habitat at many stages in its life cycle. Both ice and snow must be stable enough during spring to enable female ringed seals to raise their pups in lairs. But as the Arctic ice continues to melt each year and ice breaks up sooner, more pups may become separated from their mothers prematurely, increasing the risk of exposure and predation. Furthermore, spring rains and warm spring temperatures can also cause the roofs of lairs to collapse, resulting in similar effects (4).
In addition, as Arctic conditions warm, previously inaccessible areas will open up to humans, meaning activities such as shipping and oil exploration will become a more frequent disturbance. This will degrade habitats, while increased fishing activities may reduce fish availability for the ringed seal. Warmer temperatures may also make conditions more favourable for ringed seal parasites and pathogens, as well as reduce the seal’s immunity to these natural threats, due to increased stress from a changing environment (4).
The ringed seal is protected by a variety of laws and quotas across its range. Hunting of the Baltic seal was prohibited by the Soviet Union in 1980, by Sweden in 1986 and by Finland in 1988. Similarly, hunting of seals in Lake Ladoga was prohibited in 1980 and the population in Lake Saimaa has been protected since 1955. The Saimaa seals have also been afforded additional protection by the establishment of two national parks within the lake, as well as by the regulation of shoreline development and the banning of fishing around breeding areas, which aims to prevent entanglement in nets (1) (2).
In the United States, Alaskan Native hunters are allowed to hunt ringed seals for subsistence purposes, but other forms of exploitation are prohibited under the Marine Mammal Protection Act of 1972. The ringed seal also receives a degree of protection in a number of protected areas, including in State Nature Reserves at Franz Josef Land and in the White and Kara seas in the western Russian Arctic (1).
Find out more about the ringed seal and its conservation:
Seal Conservation Society - Ringed seal:
Marine Species Identification Portal - Ringed seal:
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
- Crustaceans: diverse group of animals with jointed limbs and a hard chitinous exoskeleton characterised by the possession of two pairs of antennae, one pair of mandibles (mouthparts used for handling and processing food) and two pairs of maxillae (appendages used in eating, which are located behind the mandibles). Includes crabs, lobsters, shrimps and barnacles.
- Gestation: the state of being pregnant; the period from conception to birth.
- Invertebrates: animals with no backbone, such as insects, worms, spiders and corals.
- Moults: in insects, referring to stages of growth, whereby the hard outer layer of the body (the exoskeleton) is shed and the body becomes larger.
- Pack ice: sea ice that floats on the surface of the water. Often formed from large pieces of ice that consolidate into a single ice mass, pack ice typically moves with currents, tides and wind.
- Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
- Territory: an area occupied and defended by an animal, a pair of animals or a colony.
IUCN Red List (February, 2011)
- Reijnders, P., Brasseur, S., van der Toorn, J., van der Wolf, P., Boyd, I., Harwood, J., Lavigne, D. and Lowry, L. (1993) Seals, Fur Seals, Sea Lions, and Walrus. Status Survey and Conservation Action Plan. IUCN Seal Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK.
Jefferson, T.A., Leatherwood, S. and Webber, M.A. (1993) FAO Species Identification Guide. Marine Mammals of the World. FAO, Rome. Available at:
IUCN (2009) Species and Climate Change: More than Just the Polar Bear. IUCN/Species Survival Commission. Cambridge, UK. Available at:
Marine Species Identification Portal - Ringed seal (February, 2011)
NOAA Fisheries Service - Ringed seal (February, 2011)
Seal Conservation Society - Ringed seal (February, 2011)
MarineBio - Ringed seal (February, 2011)
BBC Wildlife Finder - Ringed seal (February, 2011)