The beluga (or white whale) Delphinapterus leucas
Beluga видео
Striking white colour makes the beluga whale a very distinctive species. Adult male has a length of up to six metres and weighs up to two tons. In contrast to bottlenose dolphin, the white whale’s head has a bulbous melon and a short beak with a cleft upper lip. The dorsal fin is replaced by a small dorsal ridge and the pectoral fins are paddle-shaped. In summer, beluga whales stay in open coastal waters among ice floes, while in autumn, they migrate southward in large herds when the sea freezes over. In search of fish belugas often come into rivers and swim up as far as a few hundreds of kilometers from the estuary. Foraging beluga whales swim at a speed of just 1.5-2 kph but scared animals can develop a speed of up to 22 kph. These dolphins are able to spend no more than 15 minutes under water. Belugas generally live together in small groups (supposedly, family groups) of 5 to 20 individuals (these groups are called “pods”) but when fish are abundant in summer, belugas aggregate in herds of hundreds to thousands. Beluga whales feed on schooling fishes, crustaceans, and cephalopods. Belugas are social animals and very vocal communicators that emit diverse sounds including clicks, whistles, squeaks, mews, moans, cries, and clangs. They have well-developed echolocation apparatus and can perfectly use it for finding prey and avoiding dangerous objects on their path. The beluga whale is capable of learning.
Beluga whales are distributed in the arctic and sub-arctic waters. They inhabit the Arctic Ocean and its adjoining seas, including the Sea of Okhotsk, the Bering Sea, the Gulf of Alaska, and the Gulf of St. Lawrence. In severe winters, beluga whales may swim to the south and stay in coastal waters of Japan, Great Britain, and Massachusetts; they were even observed in the Baltic Sea. Belugas mate in the period from spring to autumn but mating peaks occur in the middle or late summer. Gestation lasts 11 to 12 months. The calf is dark gray and 1.5-1.6 meters long at birth. It weighs around 80 kg. It is paler by the age of two yeas, and blue-tinged white by the age of 5 years. Young beluga whale females reach sexual maturity by the age of around 6 years and males, by 6-9 years of age; at that time females measure 275 cm in body length, while males are 275-320 cm long.
