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| SCIENTIFIC
CLASSIFICATION |
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| COMMON
NAME: |
seals, true seals, earless seals, hair seals |
| KINGDOM: |
Animalia |
| PHYLUM: |
Chordata |
| CLASS: |
Mammalia |
| ORDER: |
Pinnipedia |
| FAMILY: |
Phocidae |
| GENUS
SPECIES: |
10 genera; 19 species |
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| DESCRIPTION: |
Streamlined body with a small tail. The forelimbs are short, hair-covered flippers. Do not possess the flexible pelvic girdle that otariids have thus their hind flippers cannot be tucked under the body to stand on. Land locomotion is accomplished by crawling on the belly. Do not possess a noticeable external ear structure. The snout is blunt and has numerous sensitive whiskers. Coloration varies, many species are spotted and some have banded color patterns. |
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| SIZE: |
Range extensively in size from 110-580 cm (3.6-19 ft.); males are approximately the same size as females |
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| WEIGHT: |
Range in weight from 50-5,000 kg (110-11,023 lb) |
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| DIET: |
Generally eat various fish, shell fish and cephalopods |
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| GESTATION: |
270-350 days; some species have delayed implantation |
| NURSING
DURATION |
10-80 days |
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| SEXUAL
MATURITY: |
Varies by species |
| MALE |
Generally 4-6 years |
| FEMALE |
Generally 4 years |
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| LIFE
SPAN: |
Varies; up to 45 years in ringed seals (Pusa hispida) and 14 years in male elephant seals (Mirounga leonina) |
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| RANGE: |
Coastlines and ice fronts throughout the world except the Indian Ocean. Some species are found in inland lakes. |
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| HABITAT: |
Prefer coastal areas with shallow waters near abundant food sources. |
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| POPULATION: |
GLOBAL |
Varies |
| REGIONAL |
Varies |
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| STATUS: |
IUCN |
Endangered: Hawaiian monk seal (Monachus schauinslandi), Saimaa seal (Phoca hispida saimensis)
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| Critically Endangered: Mediterranean monk seal (Monachus monachus) |
| Vulnerable: Caspian seal (Pusa caspica), Baltic seal (Pusa hispida botnica), Ladoga seal (Pusa hispida ladogensis) |
| Insufficiently Known: all other species |
| CITES |
Appendix I: Hawaiian and Mediterranean monk seals |
| USFWS |
Endangered: Hawaiian and Mediterranean monk seals |
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| 1. |
The elephant seal (Mirounga leonina) dives to 1200 m (3937 ft.) and can remain submerged for 120 minutes. |
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| 2. |
The size of seal pups at birth is approximately 10% of their mother's mass. They grow very quickly achieving two to five times their original weight in just 4-50 days. |
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| 3. |
The elephant seal is the most massive of all the pinniped species - which includes all seals, sea lions and walruses. |
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| 4. |
Leopard seals are among the top predators in the Antarctic ocean preying on fish, penguins and other seal species. |
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| 5. |
In many of the phocids, gestation includes a phenomenon called delayed implantation: when the fertilized egg divides into a hollow ball of cells one layer thick (blastocyst stage) it stops growing and floats freely in the uterus for six weeks to five months, depending upon the species. Hormonal changes in the female both cause the delay and trigger the implantation in the uterine wall, where the blastocyst resumes development. |
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| 6. |
All pinnipeds have vibrissae on their muzzles. Vibrissae are thick whiskers, each with its own blood supply and nerve ending, making it sensitive to touch. They are attached to tiny muscles that enable a pinniped to move the vibrissae voluntarily. The vibrissae transmit tactile information to the brain. |
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| 7. |
Phocids generally have more cusps (points) on their teeth than other Pinnipeds. The teeth of crabeater seals (Lobodon carcinophagus) have long, comb-like cusps, presumably for filter-feeding on krill in a manner similar to filter-feeding in baleen whales. |
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All pinniped species have been affected to some degree by human activities. Some populations have been severely impacted; others, owing to the remoteness of their ranges, have hardly been affected. Most seals, with the exception of those in the most remote areas, have been hunted for their meat, oil, hides and other raw materials. Hunting of some species continues today. Seals are also affected by chemical pollutants, marine debris, and competition with fishing industry for food resources.
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| Byrum, J. Pinnipeds From Pole to Pole: Seals, Sea Lions and Walruses. SeaWorld Education Department, 2000. |
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Nowak, Ronald M. (ed.). Walkers Mammals of the World. Vol. II. Baltimore: Johns Hopkins University Press, 1999. |
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