Fin Whale

Balaenoptera physalus (Linnaeus 1758)

Morphology and dimensions: It is the second larger animal never existed on the earth, having a length of the body that, in females, is slightly larger than males: it can reach 24 meters; the weight is between 50 and 80 tons. The length at birth is approximately 6 meters and the weight 2 tons. As all the exemplars pertaining to the family of the Balenotteridi, it is equipped with a dorsal fin and with numerous furrows in the throat.

Coloration: The back is of a basic grey-slate coloration, with clearer shadings mainly on the right side of the body, whose shape characterises every single individual. Abdomen and the right mid jaw are instead of white uniform colour.

Swim and breathing rhythm: In spite of the powerful size, the shape of the body is extremely hydrodynamic and concurs to have an elegant swim, during which it can touch the 20 nodes of speed. It can remain in apnea up to a maximum of 20 minutes and, as demonstrated by a recent research in Liguria Sea, it is able to reach a depth of beyond 400 m. Its breathing cycle is formed by two phases: in proximity of the surface, of the duration of some minutes, during which the animal swims under the surface of the water emerging regularly in order to breathe; the other, in immersion, preceded by the showy arching of the back. As difference from the Capodoglio, it nearly does not raise never the tail outside from the water.

Feeding: Common finners seen in Liguria Sea eat during summer eat exclusively “Norvegica Meganyctiphanes” that they swallow in great amounts expanding their throat furrows.

Social behaviour: The common finner is watched in small groups composed by two to three exemplars, or isolated. The real consistency of relationship between the various exemplars is not known; the only sure and long-lasting relation is the one between the mother and its small baby.

Vital cycle: Genetically distinguished from the species of the Atlantic Ocean, it is almost sure they reproduce themselves in the Mediterranean Sea. Gestation last 11-12 months, the sexual maturity appears between the 8 and 12 years of age. Among the most long-lived cetaceum it is one of the species, being able to reach 90 years.

Identification in sea: Recognisable from dimensions and for the characteristic vertical breath upside down cone shaped, 6 meters high. Another sign, which differentiates it from all the other finners is the coloration of the skilful mid jaw. The clearer shape of the dorsal fin and shadings on the skilful side of the body are typical and unique signs of Identification. These characteristics highlight in a plan of search of the Tethys Research Institute in Liguria Sea, have allowed to catalogue more than 350 common finners that which have been watched and recognised in successive years. The only “Misticete” in the Mediterranean Sea, its population in the western river basin is estimated in more than 3,000 exemplary. After the Streaked Stenella it is the more watched cetaceum.