Genre: Information/Explanation

Toothed Whales There are 66 species, or kinds, of toothed whale, grouped in several families. Some toothed whales are: Sperm, Bottlenose, Orca, Pilot, Narwhal, and Beluga whales, and dolphins and porpoises. Almost 90% of cetaceans are toothed whales. They are generally smaller than baleen whales, and have one blowhole. Males are generally larger than females. Most toothed whales are dolphins and porpoises, but there are a few large toothed whales such as Orca, or killer whale, and the sperm whale. Toothed whales are believed to be among the most intelligent animals on earth.  The intelligence of dolphins, Beluga and killer whales has been shown in captivity, and sperm whales have the largest brain of any animal. The largest toothed whale is the sperm whale , about 18 m long. It is thought to dive deeper than any other cetacean. Sperm whale breaching The Pygmy sperm whale and Dwarf sperm whales are much smaller, though similar in appearance. One of the smallest toothed whales is Hector's dolphin , about 1.3 m. Feeding Toothed whales have peglike teeth. The number and size of the teeth depend on the species. The teeth are designed for gripping food rather than chewing it. They swallow their food whole or in very large pieces. Most toothed whales eat fish, but some also eat invertebrates, such as crabs or squid. Orca whales, also called killer whales, are the most effective predators in the ocean, eating fish, seabirds, and marine mammals such as seals or other whales. Beaked Whales One family of toothed whales is known as beaked, or sword-nosed, whales. They are the least known of all cetaceans, living in deep water far from land and rarely seen. Some species have never been seen alive but have been studied only when dead ones are washed ashore. It is believed that there are 20 living species of beaked whales, including the North Pacific bottlenose whale, Shepard's beaked whale, Sowerby's beaked whale, and Stejneger's beaked whale. Narwhals and Beluga whales Another family of toothed whale has only two species: the Narwhal and Beluga whale . Neither has a dorsal fin. They have blunt- shaped heads, are grey colored at birth, and whiten as they mature.  Adult Beluga whales are a brilliant white, while narwhals have white bellies and mottled greyish backs and sides. Belugas have 8-10 teeth in each jaw. Narwhal have only two teeth in the upper jaw, one of which develops into a spiral tusk in most males and some females. Conservation Most whale species are protected. Sperm whales were once hunted for the large amount of oil that could be obtained from their blubber and from a part of their head called the spermaceti organ. In the intestines of sperm whales a waxy substance forms around the beaks of squid they have swallowed. This is called ambergris , and was used to make perfume. Huge numbers of sperm whales were killed between the 17th and 20th centuries, and they are still classified as endangered. As this 1833 picture of whalers shows, in the 19th century they rowed in small boats as they chased the whales, with one man in the front throwing harpoons to try to kill the whale. Once harpoon guns were invented and ships had engines, more and more whales were killed until most kinds of whales were endangered. Products from whales can now all be manufactured or obtained elsewhere, so there is no longer any need to hunt whales.