Toothed whales Toothed whales have teeth and a single opening at their blowhole, there are about 70 species of toothed whales including dolphins and porpoises. They are usually smaller than baleen whales and tend to be social creatures, living in groups. They range in size from the 60 foot sperm whale to the 5 foot harbor porpoise. Most toothed whales are excellent hunters and must chase and capture their prey. They eat individual prey unlike baleen whales which swallow many small animals at one time. They are carnivores and feed on fish, squid and other marine animals. Toothed whales also feed all year round and do not typically migrate. The bodies of toothed whales are usually darker on the top and lighter underneath. This is called counter-shading and makes the whales harder to see in the water. When the whales hunt, counter-shading makes it possible for them to sneak up on their prey, as the prey animals don't see the whales until it is too late. The light-colored belly blends with the sunlight sparkling on the water's surface, the dark back blends with the darkness of the deep water below. Toothed whales found in Hawai'i include: Melon-headed whale, Pygmy killer whale, False killer whale, Shortfin pilot whale, Killer whale, Sperm whale, Pygmy sperm whale, Cuvier's beaked whale, and five species of dolphins (see Dolphins for listing).
Dolphins Dolphins are toothed whales and are often referred to as "small cetaceans", although some are quite large attaining lengths of 20 feet. Names can be confusing, some dolphins are called porpoises, some porpoises are called dolphins, some dolphins are called whales and yet all dolphins are whales. Killer whales and pilot whales are the largest of the dolphins. Dolphins and porpoises refer to two different types of animals although they are closely related. Dolphins possess a distinct beak, and have round, cone-shaped teeth. Most species of dolphins are larger than porpoises. Dolphins are the largest and most diverse family of the cetacean order and includes 26 living species. Several species of dolphin are found in Hawaiian waters. They do not migrate out of the region but some do travel hundreds of miles in search of food. Dolphins are found in all oceans and major seas as well as some species found in large rivers.
Dolphins are very social creatures and often depend on social interaction for hunting, defense and reproduction. They form long lasting groups that range in size from a few animals (2-40) called pods to several hundred members known as schools or herds. Their playful curiosity and cleverness make them fascinating to watch. Being swift and acrobatic swimmers, they are the mischief makers of the sea. They love to play and will play with almost anything from feathers to sea turtles to humans. Although humans hunt them, pollute their homes, drown them in fishing nets, catch all their fish, they seem so ready to accept us as friends. Dolphins have been also known to help human swimmers in distress and even protect them from sharks. Five species of dolphins are regularly found in Hawaiian waters: the Pacific bottlenose dolphin, Rough-toothed dolphin, Spotted dolphin, Risso's dolphin and Spinner dolphin.
Spinner dolphin Spinner dolphins get their name from their habit of leaping above the surface of the water and spinning. They feed at night in the open ocean and rest and play near shore and in bays during the day. In these nearshore habitats, Hawaiian spinner dolphins engage in resting and reproductive activities vital to their survival.
Porpoises Porpoises are generally smaller. They have no distinct beak. Their foreheads slope almost uniformly to the tip of their snout and their teeth are spade-like, flat, triangular in shape. They have smaller heads than dolphins and have shorter snouts. There are six species of porpoises, none of which are found in Hawaiian waters. Threats
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