This majestic animal is the largest in the planet! Yes, even bigger than an elephant. It swims in and through all our oceans. Given its massive body, with a length of up to 33 m, and weight of up to 160,000 kg , it can consume up to 4 tons of krill per day . It gulps in tons of water, often with acrobatic turns from beneath a patch of krill prey, which is blindsided; it then rolls 180 degrees to complete the act . Sneaky isn’t it?
Sadly this animal is now classified as endangered by the IUCN Red List, because of its decreasing population being less than 12,000 at present.  Their high importance to fisheries since the 1900's for its meat and oil from the blubber contributed to its decline. Current threats are mainly ship strikes, by-catch due to entanglement, and ice entrapment in cold areas. 
To know more about blue whales (Balaenoptera musculus), visit SeaLifeBase
 Jefferson, T.A., Leatherwood, S., Webber, M.A. (1993) FAO Species Identification Guide: Marine Mammals of the World. Rome, FAO. 320 p. + 587 figures.
 Harris, S. (2012) World's largest mammal, blue whales, less than 25,000 left in Earth's oceans. The Guardian Express, posted 16 October 2012.
 Bhanoo, S.N. (2012) Acrobatic blue whales can sneak up on krill. New York Times, posted 4 December 2012.
 NOAA. Blue whale (Balaenoptera musculus). NOAA Fisheries: Office of Protected Resources http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/bluewhale.htm [Accessed 08/02/2013].