Humpback whale
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Megaptera novaeangliae

Names

Azores : "Ampebeque" - POR : Baleia de Bossa - ITA : Megattera - SPAIN : Jorobada - GB : Humpack GER : Buckewall - NEDER : Bultrug - SWEEDS : Hnufubakur - NOORS : Knølhval - DEENS : Buckelhval - JAP : Zato kujira

Biology

Male and female adults' average size is 14 and 15 m in length, respectively. Their weight varies between 30 to 40 tons. Newborns measure 4 to 5 m, and their weight varies from 1 to 2 tons. Gestation lasts about 1 year. The mother takes care of its calf until it is 1 year old. The body is basically blue and black, with a white region on the throat and belly. The head is marked by a string of protuberances (the humps). This species is distinguished by long flippers that usually have a white coloration. They have 270 to 400 pairs of gray baleen plates in the upper jaw and 14 to 35 broad ventral grooves in the throat, extending at least to the navel. Their feeding and hunting habits are variable. They can make a sudden attack on a bank of krill or on small schools of fish, or they can attack their prey with their tails or flippers. The most impressive feeding behaviour is perhaps the one in which the whales circle a school of fish or krill from below, emitting a bubble curtain as they ascend slowly to the surface and confine the prey to this " bubble net ". Finally, the whales just charge through it and engulf the prey! The oldest animal ever found was 48 years old. This whale has the largest vocal repertoire of the animal kingdom. They can produce different types of sounds with frequency ranges of 0.02 to 8.2 kHz. It is believed that each population has its own dialect. Their famous songs can last up to 15 minutes and are produced mainly by males during the reproduction time.

Observation

Victims of chase, the humpback whales almost disappeared from the North Atlantic. However, an isolated but very active animal was observed near the central group of islands of the Azores for several weeks during summer 1996. We were also able to observe this species from the land lookouts several times during 1995. In 1994, a juvenile was also observed and filmed from a sailing ship off the southern coast of Faial. We were not able to get close enough to be certain of this identification, but we were able to observe its loud and clear blow (with a height of about 2.5 m. In June 1998 and 1999 we had the opportunity to follow and fotograph two of the species on the southern coast of Pico. As soon as it dives, this species arches its back strongly and clearly lifts its tail out of the water. They can remain submerged for 20 minutes. This species swims at speeds of 4 to 8 knots. From far away, the humpback whale can be confused with the other species of its family but at close range it is easy to recognize by the humps on the back and the long fins.

Cetaceans in the Azores