Two seals in water

Scientific Classification

Order - Pinnipedia

Pinnipeds are seals, sea lions, and walruses. Some scientists classify Pinnipedia as a suborder of Order Carnivora.


Family - Phocidae

Phocidae includes all "true" seals. True seals lack external ear flaps; have a stout, round body; and are unable to rotate their hind flippers forward.


Genus, Species - Phoca Vitulina

Most scientists recognize five subspecies of harbor seals: P.v. richardsi, P.v.vitulina, P.v. concolor, P.v. mellonae, and P.v. stejnegeri. Each subspecies is separated geographically, and so is reproductively isolated. Historically, scientists classified P. largha (the largha seal) as a harbor seal subspecies. Currently, P. largha is widely recognized as a separate species. The harbor seal also is known as the common seal.


Fossil Record

  • The earliest phocid fossils date back 12 to 15 million years.
  • Ancestral phocids gave rise to modern harbor seals, which appeared in the North Pacific two to three million years ago when the Bering Strait formed.
  • The skeleton and limb structure of pinnipeds shows that the ancestors of harbor seals once were able to walk on land. Scientists, however, have not found fossil evidence to identify a common ancestor with living land mammals.