ringed seal

ringed seal
Name	Ringed seal
Status	LC
Status system	IUCN3.1
Genus	Pusa
Species	hispida
Authority	(Erxleben, 1777)
Range map caption	Distribution of the ringed seal

ringed seal is a small, abundant earless seal inhabiting the Arctic and sub-Arctic regions. It is the most common and widely distributed seal in the Northern Hemisphere, known for the distinctive light-colored rings on its dark fur. This species is a crucial component of the polar ecosystem and a primary food source for predators like the polar bear.

Description and characteristics

The ringed seal is a relatively small phocid, with adults typically measuring between 1.1 and 1.6 meters in length. Its most defining feature is the pattern of light gray rings that dot its dark gray or silverish back, a trait referenced in its scientific name, *Pusa hispida*. The species exhibits significant sexual dimorphism, with females being slightly smaller than males. It possesses strong claws on its front flippers, which are essential for maintaining breathing holes in thick sea ice. Compared to other Arctic seals like the bearded seal or the harp seal, the ringed seal has a more compact and streamlined body shape.

Distribution and habitat

This seal has a circumpolar distribution throughout the Arctic Ocean, including its adjacent seas such as the Bering Sea, the Hudson Bay, and the Baltic Sea. Distinct populations are recognized, including the Saimaa ringed seal in Finland and the Ladoga seal in Russia. Its habitat is intimately tied to ice-covered waters, where it utilizes the stable fast ice of coastal areas for breeding and molting. During the summer months, some individuals may follow the retreating ice edge northward, while others remain in more open water.

Behavior and ecology

Ringed seals are largely solitary and philopatric, often returning to the same general area annually. They are expert ice engineers, using the claws on their foreflippers to create and maintain a network of breathing holes in ice that can be over two meters thick. They also excavate lairs in snow drifts atop the ice, providing critical shelter from predators and harsh weather. These lairs are so well-hidden that they are typically located only by predators like the polar bear or the Arctic fox. Their vocalizations, which include trills and chirps, are important for communication, especially during the breeding season.

Diet and foraging

The diet of the ringed seal is diverse and varies by season and location, primarily consisting of various pelagic fish and crustaceans. Key prey items include Arctic cod, saffron cod, herring, and shrimp. They are opportunistic feeders, also consuming amphipods, euphausiids, and other invertebrates. Foraging dives are typically to depths of less than 50 meters, though they are capable of diving much deeper. Their feeding activity helps regulate prey populations and contributes to the nutrient cycle within the Arctic food web.

Reproduction and life cycle

The breeding season occurs in late March to early April on the stable fast ice. Following a gestation period of about nine months, including a delayed implantation, a single white-coated pup is born in a snow lair. This natal lair provides insulation and camouflage from predators during the vulnerable first weeks of life. Pups are weaned after 5-7 weeks, having rapidly gained weight on their mother's fat-rich milk. Sexual maturity is reached between 5 and 7 years of age. The average lifespan in the wild is 25 to 30 years, though they face high mortality in their first year from predation and environmental conditions.

Conservation status and threats

The ringed seal is currently classified as Least Concern by the IUCN due to its large and widespread population. However, several distinct subspecies, like the endangered Saimaa ringed seal, face critical threats. The primary long-term threat to the species is climate change, which causes rapid loss of sea ice essential for breeding, molting, and predator avoidance. Other significant threats include increased shipping traffic, potential oil spills, and incidental bycatch in fishing gear. Conservation efforts are coordinated by bodies like the IWC and are focused on habitat protection and mitigating human disturbances.

Category:Pinnipeds Category:Arctic fauna Category:Mammals described in 1777