Fin Whale

Common Name: Fin Whale

Class: Mammalia

Order: Cetacea

Suborder: Mysticeti

Family: Balaenopteridae

Genus: Balaenoptera

Species: Balaenoptera physalus

Taxonomy/Description

Fin whales belong to the Mammalian Order Cetacea, in the suborder Mysticeti.  All baleen whales belong to the suborder Mysticeti, which is Latin for "mustached whales".  The fin whale belongs to the rorqual family, Balaenopteridae.  The word "rorqual" means "tube whale or furrowed whale", referring to the pleats on the lower jaws of rorquals.  All rorquals have baleen, a dorsal fin and throat grooves.  Other members of this family include the humpback whale, blue whale and minke whale.  The fin whale's scientific name is Balaenoptera physalus.  Its generic name, Balaenoptera, means "winged whale", which refers to the fin whale's dorsal fin.  The fin whale's specific name, physalus, means "blow pipe", referring to the fin whale's blowhole.  The fin whale is the second largest extant animal, dwarfed only by the enormous blue whale.  One can recognize this species from its very unusual lower jaw coloration.  The left side of the lower jaw is mottled black, while the right side is cream colored.  Fin whales may exceed 80ft in length and 80 tons in weight.  Female fin whales are usually larger than males of the same age.

Habitat/Diet

Fin whales are found in all oceans.  The major food sources of fin whales living in the Northern Hemisphere are krill, euphausiids, and schooling fish.  Fin whales of the Southern Hemisphere feed euphausiids.  Temperate, tropical, and polar seas all supply the fin whale with its prey.  The whale herds schooling fish into a ball formation, then attacks the swarm by turning on its right side and opening its mouth.  The strange coloration of the lower jaw may aid in the capture of the fish.  As the whale opens its large mouth to gulp up the schooling fish, the pleats of its lower jaw expand to contain the large volume of water.  The whale then presses its tongue up against the roof of its mouth, straining the water through its 262-473 baleen plates.  These 30 inch long and 12 inch wide plates are composed of keratin, the same substance of fingernails and hair.  Strangely, the baleen on the left side of the whale's mouth alternate in dark and light bands of coloration, and the first one-third baleen on the right side of the whale's mouth is dark in coloration.  This baleen coloration may also aid in the capture of prey.  The ends of baleen are brush-like, preventing the prey from escaping.  The prey remain inside, and are consequently swallowed.

Behavior/Reproduction

Fin whales are capable of swimming at speeds of 23 miles per hour, a fast speed among cetaceans.  Whales of the Northern Hemisphere migrate from cooler northern waters to warmer equatorial waters in the autumn, returning to the cool northern waters in the spring.  The whales of the Southern Hemisphere migrate from cooler southern waters to warmer equatorial waters in the spring, returning to the cool southern waters in the autumn.  Fin whales are often seen in pairs, which may indicate monogamy.  Groups of 6-7 are not uncommon.  Mating and birthing occurs while the whales are in warm waters.  The whales do not feed during the breeding season.  Gestation lasts 11-11.5 months.  Newborn calves are 20 feet in length, weighing about two tons.  Calves nurse for 6-7 months and reach sexual maturity at 6-11 years.  Some researchers estimate individuals with lifespans up to 114 years.

Conservation

As blue whale populations decreased from the whaling industry, fin whales became the targets of whalers.  Population estimates before commercial whaling emphasized fin whale hunting exceeded 400,000.  The vast majority of these whales lived in the Southern Hemisphere.  The International Whaling Commission began to drastically lower quotas on fin whales during the late 1960's and early 1970's.  Unfortunately, the current population estimates for fin whales are far from the original numbers.  Fin whales of the Southern Hemisphere number about 15,000, those of the North Pacific about 17,000, and those of the North Atlantic about 47,000.

 

Content provided by Canisius College students under the direction of Michael Noonan, PhD.