Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Balaenopteridae
Genus: Balaenoptera
Species: B. musculus
Binomial name: Balaenoptera musculus
Subspecies: Balaenoptera musculus intermedia
Common name: Blue whale
The blue whale (Balaenoptera musculus intermedia) is a marine mammal of the Southern Ocean belonging to the baleen whale parvorder Mysticeti.
Blue whale populations were severely exploited by commercial whaling in the 20th century. This reduced the Antarctic population to less than 1% of its original size, from an estimated 200,000 animals to less than 2,000. They prefer a solitary life with occasional aggregations for breeding and foraging.
A blue whale foraging ground was identified off the South Taranaki Bight of Taranaki in 2014. 50 whales were spotted.
The blue whales are up 30 metres in length and have a maximum recorded weight of 173 tonnes They are the largest animal that has ever existed.
The blue whale's body is long and slender and can be various shades of bluish-grey dorsally and somewhat lighter underneath. The head is flat, and there is U-shaped prominent ridge running from the blowhole to the top of the upper lip. The front part of the mouth is thick with baleen plates; around 300 plates, each around one metre long, they hang from the upper jaw, running 0.5 m back into the mouth. Between 70 and 118 grooves (called ventral pleats) run along the throat parallel to the body length. These pleats assist with evacuating water from the mouth after lunge feeding.
Blue whales have twin blowholes shielded by a large splashguard. The flippers are 3–4 metres long.
The upper sides are grey with a thin white border; the lower sides are white. The head and tail fluke are generally uniformly grey. The whale's upper parts, and sometimes the flippers, are usually mottled. The degree of mottling varies substantially from individual to individual. Some may have a uniform slate-grey colour, but others demonstrate a considerable variation of dark blues, greys and blacks.
Blue whales feed almost exclusively on krill, though they also take in small numbers of copepods.
Blue whales do not use echolocation to navigate. They have the loudest, strongest vocalisations of all the whale species. This may be an adaptive feature of their solitary nature, enabling widely distributed individuals to keep track of other blue whales through contact calls.
Blue whale with its bow wave, showing the blowhole.
Blue Whale Tail Fluke Diving. It is very rare to see the tail fluke of a Blue Whale upon diving.
Blue Whale skeleton outside the Long Marine Laboratory of the University of California, Santa Cruz.
A 5.8 metres long Blue Whale Skull at the Smithsonian Museum of Natural History.
Thanks to Wikipedia for text and information:
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