What's the difference between a seal and a sea lion?

Seals and Sea Lions (and Walruses)

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Seals and sea lions share many characteristics -- that's why they're in the same suborder after all -- but there are a few important features we can use to distinguish them. To examine where the subtle differences occur, let's look closer at these pinnipeds.

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when looking at these pups.

  • Phocidae: This is the family where we find true or earless seals. Phocids have no external ears, although they do have ear holes. The seals' front flippers are generally furry, small and weak, so these marine mammals move on land by using their diminutive forward appendages to wiggle forward. They use their back flippers to generate powerful strokes when swimming in the water.Some common species of phocids include harp seals (the most populous species of seal) and harbor seals.
  • Otariidae: The otariids, sea lions and fur seals, have little external ear flaps that poke out of the sides of their heads (hence why members of this family are also referred to as eared seals). Another big difference between true seals and these guys is that sea lions and fur seals have larger, hairless flippers which they use more effectively on land. Sea lions and fur seals can rotate their hind flippers toward the ground so they're able to walk on all four appendages. Otariids make use of their fore flippers when propelling themselves through water.Well-known sea lion species include the California sea lion and the steller (or northern) sea lion. Fur seals, which tend to have thicker coats and longer flippers than sea lions, include the Guadalupe fur seal, the northern fur seal and the Galapagos fur seal.
  • Odobenidae: The sole surviving species of this family is the walrus. There are two walrus subspecies -- one living in the Pacific Ocean and one in the Atlantic. Embracing characteristics of both of the previously mentioned families, walruses have little fur and no external ears. What they do have is the otariid ability to move on land by using their hind flippers. They make use of both their fore flippers and hind flippers while swimming. They also possess tusks and can grow extremely large, with males weighing up to about 3,000 to 4,000 pounds (1,300 to 1,800 kilograms). For more information about odobenids, read How Walruses Work.
These Atlantic walruses relax on ice. These Atlantic walruses relax on ice.
These Atlantic walruses relax on ice.
Paul Nicklen/National Geographic/Getty Images

Now that you know all about pinnipeds -- and how to tell them apart -- you're ready to seal the deal and impress your friends the next time you're at the beach. Go to the next page for some great links about seals, sea lions, walruses and other creatures of the sea.

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More Great Links


  • "2007 IUCN Red List." International Union for Conservation of Nature and Natural Resources. 2007. (7/1/2008)http://www.iucnredlist.org/search/search-basic
  • "Endangered Marine Mammals." The Marine Mammal Center. (7/1/2008)http://www.marinemammalcenter.org/learning/education/mammalinfo/endanger.asp#top
  • "Fur Seal." Encyclopedia Britannica. 2008. (7/1/2008)http://www.britannica.com/EBchecked/topic/222512/fur-seal
  • Higden, Jeff et al. "Phylogeny and divergence of the pinnipeds (Carnivora: Mammalia) assessed using a multigene dataset." BMC Evolutionary Biology. 11/9/2007. (7/1/2008)http://www.biomedcentral.com/1471-2148/7/216"
  • Marine Mammal Classification." The Marine Mammal Center. (7/1/2008)http://www.marinemammalcenter.org/learning/education/mammalinfo/classification.asp
  • "Pinniped." Encyclopedia Britannica. 2008. (7/1/2008)http://www.britannica.com/EBchecked/topic/461139/pinniped
  • "Pinnipeds: Seals, Sea Lions, and Walruses." National Oceanic and Atmospheric Administration's National Marine Fisheries Service's Office of
  • Protected Resources. (7/1/2008)http://www.nmfs.noaa.gov/pr/species/mammals/pinnipeds/
  • "Seal." Encyclopedia Britannica. 2008. (7/1/2008)http://www.britannica.com/EBchecked/topic/530868/seal
  • "Seals, Sea Lions, and Walruses." SeaWorld Education Department. (7/1/2008)http://www.seaworld.org/just-for-teachers/guides/pdf/s&sl-4-8.pdf
  • "Sea Lion." Encyclopedia Britannica. 2008. (7/1/2008)http://www.britannica.com/EBchecked/topic/530626/sea-lion
  • "Sea lions and seals--what's the difference?" San Diego Zoo's Animal Bytes. (7/1/2008)http://www.sandiegozoo.org/animalbytes/t-sea_lion.html
  • "The Pinnipeds: Seals, Sea Lions, and Walruses." The Marine Mammal Center. 1/2001. (7/1/2008)http://www.marinemammalcenter.org/learning/education/pinnipeds/pinnipeds.asp
  • "Walrus." Encyclopedia Britannica. 2008. (7/1/2008) http://www.britannica.com/EBchecked/topic/635052/walrus
  • "What's the difference between a seal and a sea lion?" North Carolina Aquariums. 10/15/2005. (7/1/2008)http://www.ncaquariums.com/askaquarium/seal.htm