Sealife guideOcean giants: exploring the sea mammalsMarine vertebrates

Last updated on 08/13/2025 at 12:24 AM

Marine mammals include notably the cetaceans such as whales, dolphins, orcas and sperm whales, as well as pinnipeds like seals, walruses, sea lions and finally the sirenia which include manatees.

Marine mammals are characterized by a respiratory system made up of lungs. They therefore need to regularly surface to breathe.

Cetaceans

Cetaceans comprise more than 80 different species and are divided into two subgroups: the baleen whales, also called Mysticetes and the toothed whales, also called Odontocetes.

Baleen whales

Anatomy of baleen whales

Toothed Whales

There are about thirty species of dolphins, all grouped within the family of Delphinidae.

Common bottlenose dolphin
(Tursiops truncatus)

Short-beaked common dolphin
(Delphinus delphis)

Spinner dolphin
(Stenella longirostris)

White headed dolphin
(Cephalorhynchus hectori)

Pinnipeds

The term « pinniped » may not be very familiar at first, but in fact, pinnipeds include three major families of marine animals you know well: sea lions, seals and walruses.

Antarctic fur seal
(Arctocephalus gazella)

Australian sea lion
(Neophoca cinerea)

Harbor seal
(Phoca vitulina)

These families also include other marine animals whose distinctive traits are sometimes hard to grasp, such as sea lions and elephant seals.

Discover sea mammals

Atlantic spotted dolphin
(Stenella frontalis)

Fin whale
(Balaenoptera physalus)

Gray whale
(Eschrichtius robustus)

Harbor seal
(Phoca vitulina)

Humpback whale
(Megaptera novaeangliae)

Southern right whale
(Eubalaena australis)

Striped dolphin
(Stenella coeruleoalba)

White headed dolphin
(Cephalorhynchus hectori)

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