Porpoise

A porpoise is a small toothed whale in the family Phocoenidae. Porpoises generally have blunt snouts, compact bodies, and spade-shaped teeth, unlike the more varied dolphins.

Cetacea: The order of mammals comprising whales, dolphins, and porpoises. Porpoises are cetaceans adapted to life entirely in water.
Harbor porpoise: A small porpoise found in cool coastal waters of the North Atlantic and North Pacific. It is a widespread, familiar example of the family.
Echolocation: A biological sensing process that uses returning echoes from emitted sounds to locate objects. Porpoises use echoes to detect prey and navigate in dim or murky water.
Bycatch: The unintended capture of non-target animals during fishing. Entanglement in fishing gear is a leading direct threat to several porpoise populations.
Odontoceti: The cetacean group of toothed whales, including dolphins, porpoises, and sperm whales. Porpoises belong to this group and use teeth rather than baleen.
Dall's porpoise: A large, fast-swimming porpoise native to the North Pacific. Its bold black-and-white pattern and speed contrast with many coastal porpoises.
Porpoise sonar: The high-frequency echolocation system used by porpoises to sense underwater surroundings. Its narrow-band clicks help distinguish small targets in cluttered coastal habitats.
Vaquita conservation: Efforts to prevent the extinction of the vaquita in the Gulf of California. Its recovery depends on stopping illegal gillnet fishing in its range.
Phocoenidae: The family of toothed cetaceans known as porpoises. This family defines which species count as porpoises.
Vaquita: A critically endangered porpoise found only in Mexico’s northern Gulf of California. Its near-extinction shows how fisheries can threaten a single porpoise population.

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