Beluga or White Whale, toothed whale, closely related to the dolphin, with a clearly defined head and short fins. Belugas (derived from the Russian byelukha, meaning "white") are born either black or dark brown, without dorsal fins, and turn milky white in about five years. Males can attain a maximum length of 7.0 m (23 ft) and a weight of 1 metric ton; females are somewhat smaller. Belugas travel in schools of several thousand, feeding on fish, octopus, crabs, snails, and squid. They are common to the Arctic Ocean and travel as far south as the state of New Jersey in the United States and the Rhine River in Europe.