FaunaHub

Whale

Marine MammalCetaceanMigratory

Humpback whale (Megaptera novaeangliae) breaching out of the ocean with a large splash.

Humpback whale (Megaptera novaeangliae) breaching.

Image: Giles Laurent, CC BY-SA 4.0, via Wikimedia Commons.

Overview

Whales are large marine mammals of the infraorder Cetacea, divided broadly into baleen whales (Mysticeti) and toothed whales (Odontoceti, which also includes dolphins and porpoises). Like all cetaceans, whales are fully aquatic descendants of land-dwelling ancestors and breathe air through blowholes at the top of the head.

Habitat & Range

Whales inhabit every major ocean. Many baleen whale species — including the humpback whale (Megaptera novaeangliae) — undertake very long seasonal migrations between high-latitude feeding grounds and warmer breeding grounds. Several toothed whale species occupy specific habitats, from coastal shelves to deep open ocean.

Diet

Baleen whales filter feed on krill, small fish, and other small marine prey, using baleen plates instead of teeth. Toothed whales are active predators of fish, squid, and — in some species — other marine mammals. Diet specifics vary widely between species.

Behavior

Many whale species exhibit complex acoustic behaviour. Humpback whale "songs" — long, structured vocal sequences produced primarily by males on breeding grounds — are well documented and show year-to-year cultural change. Other species use echolocation, complex clicks, and social vocalisations. Breaching and surface behaviour are commonly observed, although their precise function is still studied.

Human Interaction & Conservation

Commercial whaling in the 19th and 20th centuries devastated populations of many large whale species. The International Whaling Commission imposed a moratorium on commercial whaling in 1986; some species have since recovered substantially, while others remain depleted. Modern threats include ship strikes, entanglement in fishing gear, ocean noise, climate change, and pollution. Conservation status varies sharply by species; check the IUCN Red List for any specific species of interest.

Similar Animals

Other cetaceans include dolphins and porpoises. The orca or killer whale (Orcinus orca) is, by classification, the largest member of the dolphin family Delphinidae rather than a baleen whale.

Frequently Asked Questions — Whale

Are whales fish?
No. Whales are mammals — they breathe air, give birth to live young, nurse with milk, and are warm-blooded. They share an ancient land-mammal ancestry with hippos and other artiodactyls.
How long can whales hold their breath?
Diving capacity varies dramatically by species. Sperm whales and beaked whales can dive for over an hour to great depths; smaller cetaceans surface much more frequently. Authoritative species accounts give specific figures.
Do whales sleep?
Yes, but in modified ways. Many whale species sleep with one hemisphere of the brain at a time, allowing breathing to continue. Sleep patterns have been studied most thoroughly in toothed whales such as dolphins.
Are whales endangered?
Status varies sharply by species. Some, like the North Atlantic right whale and vaquita (a porpoise), are critically endangered. Others, like the humpback whale, have recovered substantially since the 1986 moratorium on commercial whaling. Verify per species on the IUCN Red List.

Sources and further reading

Authoritative wildlife references used for general educational context. Conservation status should always be verified against current IUCN Red List data. External links open in a new tab.