Fin Whale – Detail Page

English Name:

Fin Whale

Scientific Name:

Balaenoptera physalis

Other Names:

Bayena (Papiamentu)

Finback, Razorback (Nicknames)


Size – Length: 22 to 26 m (~72.2 to 85.3 ft). Weight: 40 to 80 MT (~ 44.1 ST). Females are slightly larger than males.

Body shape – Long, streamlined body with a V-shaped, flattish head.

Coloring – Dark grey to brown back and sides, white undersides.

Distinct features – 1) Prominent, curved dorsal fin located on lower back.; 2) Asymmetrically colored jaws: the lower right jaw is white, while the lower left jaw is dark; 3) many grooves that extend from its throat to its belly.

Species Ecology


  • Prey: krill, squid and small schooling fish
  • Feeding technique: filter feed with baleen plates

Life History

  • Sexual maturity: between 8 and 12 years of age;
  • Mating season: winter, in warm waters.
  • Gestation period: 12 months
  • Calving season: winter, in warm waters.
  • Number of calves: 1, every 3 years. They are nursed for 6 months.
  • Life expectancy: 80 to 90 years.


Found in all oceans, although they are not common in tropical or polar waters. There are two subspecies: one occurs in the south (B. p. quoyi) and the other occurs in the north (B. p. physalus). These subspecies never cross paths. Fin whales migrate over long distances; they breed in warm waters in fall and water, and feed in cold waters at a higher latitude in spring and summer.


Deep, offshore waters as well as coastal waters deeper than 200 m (~656 ft).

Island Status

Uncommon; migrant

Conservation Status

  • IUCN Red List: Classified as Endangered (En).
  • CITES: Listed on Appendix I.
  • Protected from legal hunting in US waters under the Marine Mammal Protection Act (1972).

Local Research and Conservation Efforts

The St. Maarten Nature Foundation launched the Marine Mammal Monitoring project in 2011, which takes place every year from February to May, and is a wide scale census of all marine mammals found within the territorial waters of St. Maarten/St.Martin.

Did you know?

  • Fin whales are fast swimmers (the fastest of all large whales), and have earned the nickname of “greyhounds of the sea”. They swim up to 37 km/h (~ 23 mph).
  • Male fin whales attract females with low-frequency sounds; scientists believe that these are used because they travel far in water, which is important because fin whales have no specific mating grounds and have to find each other.