Great Blue Whale

(Balaenoptera musculus), a mammal of the Balaenopteridae family.

The great blue whale is the largest animal ever to have lived; the length reaches 33 m and the weight. 150 tons. The color of the back is dark gray with a dark bluish cast, while the abdomen and sides are light blue and spotty (the light spots are the result of skin damage by external parasites). The dorsal fin is small. There are 70–120 longitudinal plicae, or bands, on the abdomen. The upper jaws have 350–400 pairs of black whalebone plates. The whale’s range is very extensive but it has been nearly exterminated: in 1930 there were 200,000 in the southern hemisphere, but by 1965 no more than 1,000 remained. Hunting of the animal was prohibited in 1966.

The great blue whale feeds on krills (planktonic crustaceans). The female bears young (6.5–8 m in length) once every two or three years and nurses for seven or eight months. Sexual maturity is reached in the fourth or fifth year. A single great blue whale will yield an average of 15–20 tons of blubber and 35–40 tons of meat.