The porpoise is a sea animal with a rounded head and blunt snout. Its name means pig fish. It is a small, toothed whale that lives in warm, shallow coastal waters. Porpoises are related to the large whales and dolphins and belong in the same group of animals called the cetaceans, meaning large sea animals. These hairless, fish-like animals are sea mammals that bear their young alive and suckle them.
   Porpoises swim near the surface of the water, traveling in large schools or herds. Sometimes these schools include several hundred porpoises. They are air-breathing animals. Warm air is exhaled through a single breathing hole (blow-hole) on the porpoise's head. This warm air vaporizes into a hissing jet of steam when it is expelled into the colder outside air.
   The common porpoise is about six feet long, weighing from 100 to 120 pounds. Its smooth whalelike body is black above and white below. It has a triangular dorsal fin in the middle of its back. This porpoise has twenty-five pairs of short, sharp teeth in each jaw. It eats salmon, mackerel, herring, cuttlefish, and crustaceans. Schools of these porpoises often travel great distances in their search for food. Baby porpoises, about three feet long, are born in the spring. They, like other mammals, are nursed by their mothers.