The ringed seal (Phoca hispida) is a marine mammal that lives in Arctic regions from about 35 degrees North to the North Pole.
Ringed seals are one of the smallest seal species. They grow to about 5 feet in length and 100-150 pounds in weight. They get their name from the light gray rings that cover their dark coat. They have a silvery gray belly. They have claws on their flippers that they can use to scratch breathing holes into the ice. These seals can survive on the ice due to their thick blubber layer, which provides insulation against cold ice and seas, and an energy source if prey is scarce.
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Carnivora
- Family: Phocidae
- Genus: Pusa
- Species: hispida
Habitat and Distribution:
Ringed seals live primarily on ice, spending little time in the open ocean, although they can seek shelter by hiding under solid ice, and breathing through cone-shaped holes that they dig with the claws on their front flippers.
When there is snow on the ice, ringed seals will build caves in the snow. They use these lairs for resting and giving birth.
Both males and females become sexually mature at 5-6 years. Ringed seals mate in the spring (April-May). Males smell strongly of gasoline due to a scent that comes from glands in their faces. One benefit of this strong smell is that both hunters and polar bears avoid males at this time of year.
Females exhibit delayed implantation - the embryo isn't implanted until July or August. The total gestation period is about 11 months, after which a small pup about 10 pounds in weight is born in a snow cave. Pups are born with a coat of white fur called lanugo, which is shed after 2-3 weeks. They nurse for about 2 months.
The lifespan of ringed seals is thought to be about 40 years.
Conservation and Predators:
Ringed seals are listed as least concern on the IUCN Red List. They are one of the most common seal species in the Arctic.
Threats to ringed seals include polar bears(their main natural predators), hunting (by native hunters), pollution, oil exploration, coastal development, and climate change. These seals use the ice for breeding, moulting, and resting, so they are a species thought to be very vulnerable to global warming.
In December 2012, several subspecies of ringed seals were listed under the Endangered Species Act. This included four subspecies of ringed seals (the Arctic, Okhostsk and Baltic subspecies were listed as threatened and the Ladoga subspecies was listed as endangered), who live off Alaska and Russia. The listing was due to the likelihood of a "significant decrease in sea ice later this century."
An "unusual mortality event" occurred in 2011, when over 100 ringed seals (some dead) were discovered with skin lesions, the cause of which has not yet been determined. Read more here.
References and Further Reading:
- Alaska Department of Fish and Game. Ringed Seal Species Profile. Accessed January 31, 2013.
- Berta, A.; Churchill, M. 2012. Pusa hispida Schreber, 1775. Accessed through: World Register of Marine Species, January 31, 2013.
- Kovacs, K., Lowry, L. & Härkönen, T. (IUCN SSC Pinniped Specialist Group) 2008. Pusa hispida. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. , Accessed January 31, 2013.
- National Geographic. Ringed Seal. Accessed January 31, 2013.
- National Marine Mammal Laboratory. Ringed Seals Accessed January 31, 2013.
- NOAA Fisheries: Office of Protected Resources. Ringed Seal Accessed January 31, 2013.