By fisheries.noaa.gov, fisheries.noaa.gov.
Dolphins and porpoises, along with whales, belong to a group of marine mammals called “cetaceans.” Cetacean comes from the Latin word for “large sea creature.” Dolphins and porpoises are further classified as toothed whales, or “odontocetes.” They are highly intelligent animals that use echolocation to find food, communicate, and navigate. As with all marine mammals, they both come to the surface to breathe.
Although dolphins and porpoises are similar, they are not the same. There are some physical characteristics and behaviors you can look for to tell the difference between dolphins and porpoises.
How to Recognize a Dolphin
Dolphins typically have longer, leaner bodies than porpoises. They have hooked or curved (falcate) dorsal fins, resembling a sickle. Their faces have clearly defined, elongated “beaks,” and their teeth are pointed and cone shaped.
Dolphins are “talkative,” communicating with each other through sounds made through their blowholes. These include clicks, squeaks, buzzes, and whistles. Dolphins are highly social animals and may be seen in large groups known as pods. They are more curious around humans and may approach boats—but for your safety and theirs, you should remain at least 50 yards away.
Dolphins are found in every ocean. There are more than 30 dolphin species, including the short-beaked common dolphin, one of the most abundant cetacean species in the world.
How to Recognize a Porpoise
Porpoises have smaller, more stout bodies compared with dolphins. They have triangular dorsal fins and short faces with rounded beaks. Their teeth are flat and spade shaped.
Read the full article here: Is It a Dolphin or a Porpoise?
