- The sperm whale. Scientific name: Physeter macrocephalus
The sperm whale is the largest toothed cetacean in the world with a length of about 18 meters and a weight of more than 30 tons for large males. Females are much smaller (up to 13 meters long), so sexual dimorphism is pronounced in this species.
Feeding on cephalopods at great depths, the sperm whale is described as a great diver: it dives up to 2000 m deep and can stay in apnea for 45 min. To reduce its energy loss, the sperm whale has an unusual adaptation: spermaceti. This organ is formed of a huge pocket of lipids located in the head of the sperm whale (hence its original form). When hot, the spermaceti is liquid, sparse and the animal floats. When he wants to dive, he solidifies his spermaceti which becomes denser and the sperm whale descends in the depths head first, almost without a flick. The circulation of his blood is directly related to the density of spermaceti that the sperm whale is able to regulate to adapt his diving profile, making him a great rival for physicists!
In addition to this organ, the sperm whale has ambergris in its intestines, allowing it to digest the beaks of cephalopods it feeds. Spermaceti + grey amber made him a highly coveted animal by the whalers who hunted him from the 1700s.
It was after the sinking of the whaling ship "Essex" off South America in 1820 because of a sperm whale that the description of a sperm whale (dubbed Mocha Dick) riddled with harpoons off the coast of Chile in the 1830s that the novel Moby Dick was born in 1851.
The sperm whale is listed as Vulnerable by the IUCN Red List and is listed as Appendix I of CITES and Appendices I and II of the CMS.
More information on the conservation status on the following link: http://www.iucnredlist.org/details/41755/0