Bryan McAllister’s personal reference notebook
July 27, 2026Short & citedBlog
Civic Viewpoint.
A quiet encyclopedia with a personal desk
Kept by Bryan McAllister — short guides, clear facts, and the Canadian angle when it matters.
Field Notes • Marine Mammals

Dolphin

Dolphins are a widely distributed group of toothed marine mammals in the order Cetacea, found in oceans and, for some species, rivers and estuaries.

Updated July 27, 20261 min readCited sources

Dolphins are highly intelligent marine mammals found in oceans, coastal waters, and some rivers worldwide. They are carnivores that rely on echolocation and complex social behaviour to hunt fish and squid.

What it is

Dolphins are toothed whales in the order Cetacea — marine mammals, not fish. They breathe air, give birth to live young, and nurse their offspring. Most species live in warm or temperate waters, though a few range into colder regions.

Diet and habitat

Dolphins are active predators that eat mainly fish and squid, plus crustaceans depending on species and location. They occupy a wide range of aquatic habitats: oceans, coastal waters, estuaries, and, for some species, freshwater rivers.

Conservation in Canada

Canada hosts several dolphin species in its Atlantic and Pacific marine waters. Conservation efforts address marine mammal protection and bycatch risks. Dolphin conservation status varies widely — some species are Least Concern, others Critically Endangered.

In short

  • Dolphins are carnivorous mammals, not fish.
  • They live in marine, brackish, and freshwater habitats worldwide.
  • Conservation status differs by species; some are endangered.
  • Echolocation and complex social behaviour are key traits.
Canadian angle

Canada has several dolphin species in its marine waters, including coastal and offshore Atlantic and Pacific habitats, and Canadian conservation efforts address marine mammal protection and bycatch risks.

Quick questions

What do dolphins eat?
Dolphins are carnivores that mainly eat fish and squid, and many species also eat crustaceans such as shrimp and crabs.
Are dolphins endangered?
Some dolphin species are endangered or critically endangered, but others are not threatened. Conservation status varies widely by species.
Where do dolphins live?
Dolphins live in oceans, coastal waters, estuaries, and, for some species, rivers and other freshwater or brackish habitats.

Sources

  1. Dolphin World — https://dolphinworld.org/dolphin-diet/
    Supports: Dolphins are carnivores; diet includes fish, squid, jellyfish, shrimp, octopus; habitat range includes rivers, estuaries, coastal waters, and open ocean.
  2. Wild Dolphin Project — https://www.wilddolphinproject.org/diets-of-dolphins-whales-and-more/
    Supports: Dolphins primarily feed on fish, squid, and crustaceans; dolphins are intelligent and social.
  3. A-Z Animals — https://a-z-animals.com/blog/what-do-dolphins-eat/
    Supports: Dolphins are carnivores; diet includes fish, squid, crustaceans, jellyfish; some larger species may prey on larger marine animals.
  4. SeaWorld — https://www.seaworld.org/animals/all-about/bottlenose-dolphin/diet
    Supports: Bottlenose dolphin diet includes fish, squids, crustaceans; adults eat about 4% to 6% of body weight daily.
  5. IFAW — https://www.ifaw.org/animals/dolphins
    Supports: Dolphins are carnivorous apex predators; habitat range includes saltwater and freshwater; conservation status varies from Least Concern to Critically Endangered; dolphins are mammals.
  6. Wikipedia — https://en.wikipedia.org/wiki/Dolphin
    Supports: Dolphins are widespread in marine, brackish, and freshwater bodies; diet largely fish and squid; some large-bodied dolphins prey on larger marine animals.