Fin Whale
(Balaenoptera physalus)
Second in size only to the blue whale, the fin whale is the largest whale known to breach. Famed for its ability to sustain speeds of almost 40 km/hour, the species is sometimes referred to as the “greyhound of the sea”. It was for this reason that the fin whale was not initially targeted by early whalers. However, the species suffered the most drastic declines of any of the rorquals following the onset of modern commercial whaling. Almost 750,000 fin whales were reportedly taken from the Southern Hemisphere alone between 1904 and 1979. Although commercial whaling has now been banned, scientists fear that it may be too late for the species to recover from such a massive population decline.
Urgent Conservation Actions
Areas of critical habitat should be identified and protected. Monitoring programmes should continue. Immediate threats resulting from human activity should be addressed.
All the major oceans of the world.
Evolutionary Distinctiveness
Order: Cetacea
Family: Balaenopteridae
Early cetaceans are known from 50 million year old fossils found in India and Pakistan, along the ancient Tethys Sea which separated Africa from Asia and southern Europe. These early members of the cetacean clade (Ambulocetus, Indocetus, Pakicetus and Rodhocetus) were dolphin-sized amphibious mammals called archaeocetes, which vaguely resembled something between an otter and a crocodile. They had reduced hind limbs, but probably propelled themselves through the water using up-and-down movements of a strong tail, as do living cetaceans. It was long thought that these early whales were closely related to an extinct group of primitive carnivorous mammals called mesonychids, but molecular data now indicate that cetaceans are most closely related to hippos. Cetaceans are now grouped together with artiodactyls in a new clade, Cetartiodactyla. Around 50-35 million years ago the archaeocetes diversified and spread into deeper oceanic waters, with genera such as Basilosaurus and Dorudon well represented in the fossil record. By 30 million years ago, most of the archaeocetes were extinct, and two distinct new suborders had evolved, the mysticetes (baleen whales) and odontocetes (toothed whales). The living mysticetes are filter feeders, with baleen plates instead of teeth. They comprise 4 living families (the Balaenidae, Balaenopteridae, Eschrichtiidae and Neobalaenidae). The Balaenopteridae (rorqual family) comprises at least 7 species, including Bryde’s whale, humpback whale, minke whales, fin whale, sei whale and blue whale. The taxonomy of many of these species is complex, and there may be several more closely related species waiting to be recognised. The fin whale is believed to have diverged from the blue whale around 5 million years ago (shortly after humans diverged from chimpanzees). Remarkably, these two species have been known to hybridize.
Head and body length:
Male: 19 m
Female: 20 m
Weight: approx. 70,000 kg
The fin whale is the second largest animal on the planet. It can reach up to 27 m in length, and is sometimes mistaken for its larger relative, the blue whale. Named after its prominent dorsal fin, which is strongly curved and often reaches up to 60 cm in length, the fin whale is more slender than the blue whale. It has a more pointed snout and can also be distinguished from its larger relative on the basis of skin colouration. The fin whale is brownish-grey above and white below. The colour pattern is asymmetrical, especially on the lower jaw, which is white on the right side and dark on the left. There is a series of 56-100 pleats or grooves on the underside of its body extending from under the lower jaw to the navel. On each side of the upper part of the mouth is a row of 350-400 baleen plates. The fin whale is one of the fastest species of whale, being able to sustain a speed of around 37 km per hour. It can reach depths of up to 230 m, and is the largest whale known to breach. As with other rorquals, the females tend to be slightly larger than males.
A highly migratory species which moves to high-latitude feeding grounds during spring and summer and returns to southerly temperate waters for mating and calving during autumn and winter. Northern and southern populations never meet because the seasonal patterns are reversed in the two hemispheres, meaning that they migrate to the equator at different times of year. The species is often seen swimming alone or in pairs, although the usual group size is 6-7 individuals. These pods may be part of a wider group of up to 300 individuals spread over a wider area. Fin whales feed by filtering planktonic crustaceans (krill), fish and squid through their baleen plates. During feeding, large volumes of water and food can be taken into the mouth because the pleated grooves in the throat expand. As the mouth closes water is expelled through the baleen plates, which trap the food on the inside near the tongue to be swallowed. Unlike other rorquals, fin whales lunge-feed instead of skimming, by accelerating quickly and turning or rolling into a large school of prey. They often turn on their sides with the right side facing downward. Researchers speculate that in this position the lighter coloration of the head makes it less visible to the intended prey. There is very little, if any, feeding during the autumn and winter, when the whales are in lower lattitudes. Sexual maturity is reached at around 6-11 years, and females give birth to a single offspring every 2-3 years thereafter. The gestation period is 11-11.5 months, meaning that both mating and calving occurs when the whales are in warm waters. Calves are about 6.5 m long and weigh 1,800 kg at birth. They nurse for about 6-7 months, during which time they almost double in length. They then return with the group to the polar feeding grounds. This species is estimated to live around 80 years in the wild.
Fin whales occur both in the open ocean and in shallow coastal waters.
The species has a global distribution, occurring in the north Pacific, north Atlantic, Indian and Arctic Oceans and in the Mediterranean. They are relatively rare in tropical or polar seas. There are two main populations, one in the Southern Hemisphere and one in the Northern Hemisphere.
Population Estimate
The number of mature individuals in the world prior to exploitation is estimated at 470,000, of which 400,000 were in the Southern Hemisphere. Recent surveys indicate that there are now fewer than 15,000 fin whales in the Southern Hemisphere and around 40,000 in the Northern Hemisphere.
Population Trend
Classified as Endangered (EN A1d) on the 2010 IUCN Red List of Threatened Species.
Rorquals have long been hunted for their meat, blubber, oil and baleen. Fin whales were not initially targeted by early whalers because of their speed. However, the species declined dramatically following the onset of modern commercial whaling and the subsequent decline of the blue whale. Almost 750,000 fin whales were reportedly taken from the Southern Hemisphere alone between 1904 and 1979. Whaling of the species reached its peak between 1952 and 1962 when in excess of 30,000 animals were taken annually. Although commercial whaling has now been banned, scientists fear that it may be too late for the species to recover from such a massive population decline. Around ten fin whales are killed each year by whalers on the west coast of Greenland, under an agreement with the International Whaling Commission (IWC) to allow subsistence whaling in the area. There are some fears that this may be having a detrimental effect on the population. Today, the major threat to this species is accidental mortality resulting from collisions with boats; since fin whales often occur near the coast, they are at risk from colliding with boats in shipping lanes. The species may also be at risk from disturbance from seismic operations, entanglement in fishing gear, pollution (including noise pollution, increasing amounts of plastic debris at sea, oil spills and dumping of industrial wastes), and a decrease in krill as a result of climate change.
Conservation Underway
Numbers are beginning to recover, following a moratorium on the hunting of fin whales in 1985. Stocks in the North Atlantic off Iceland and Newfoundland are listed on Appendix II of CITES, which means that the species can be hunted only in small numbers for cultural or research purposes. All other stocks are on Appendix I. The species is also listed on Appendix I of the Convention on Migratory Species (CMS or the Bonn Convention). The IWC is the co-ordinating body for whale research and conservation. It governs the conduct of whaling throughout the world, designates specific areas as whale sanctuaries and supports whale research. There are currently whale sanctuaries in the Antarctic, Indian and Southern Oceans, where all commercial whaling is prohibited. As part of its Southern Ocean Whale and Ecosystem Research Programme (SOWER) the IWC is conducting a series of international cruises in the Antarctic. One of the aims of the 2005/2006 cruise is to undertake a feasibility study for fin whale research in waters north of 60°S, involving a sighting survey, acoustic sampling and biopsy sampling of the skin for genetic analyses. The fin whale is covered by a number of international agreements, and several countries are undertaking fin whale research and conservation work. This includes identifying areas of critical habitat, investigating species abundance and distribution, and mitigating the threats to the species. The UK Biodiversity Action Plan aims to maintain the current range and abundance of the fin whale in UK waters by reducing the discharge of pollutants and reducing disturbance from physical and acoustic sources.
Conservation Proposed
Further research is needed into the population and distribution of this endangered species. Areas of critical habitat should be identified and protected, and monitoring programmes should continue. The immediate threats must be addressed, with the recovery strategy focussing on managing human activities (including fisheries, vessel traffic, whale watching, and activities that cause cetacean habitat degradation and loss) to mitigate negative impacts on the species. International co-operation is essential to the successful recovery of the fin whale.
Ocean Alliance - Whale Conservation Institute (WCI)
This institute was established in order to protect whales and their ocean environment through scientific research and education.

Whale and Dolphin Conservation Society (WDCS)
The WDCS is the global voice for the protection of whales, dolphins and their environment.

UK Biodiversity Action Plan: Grouped Plan for Baleen Whales
This UK collaborative effort aims to monitor, assess and develop a strategic plan to ensure the long term survival of the fin whale.


Clapham, P. J., Young, S. B. and Brownell, R. L. Jr. 1999. Baleen whales: conservation issues and the status of the most endangered populations. Mammal Review 29(1): 35-60.

International Whaling Commission (IWC)

Nowak, R. M. 1999. Walker’s Mammals of the World. Sixth edition. The Johns Hopkins University Press. Baltimore and London.

Reeves, R. R., Smith, B. D., Crespo, E. A. and di Sciara, G. N. (Compilers). 2003. Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World's Cetaceans. IUCN/SSC Cetacean Specialist Group. IUCN: Gland, Switzerland.

Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. 2008. Balaenoptera physalus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. www.iucnredlist.org. Downloaded on 14 November 2010.

Whale and Dolphin Conservation Society (WDCS)

Distribution map based on data provided by the IUCN Global Mammal Assessment.

if you can provide new information to update this species account or to correct any errors, please email us at info@edgeofexistence.org

Forum comments
  1. wildtvm

    hi.. I belong to Trivandrum, almost the southernmost tip of Indian sub-continent. Couple of days before a dead whale was washed ashore nearby. The veterinarians confirmed that the death happened couple of weeks before.. but they could not clearly identify it. My friend, who is an aquatic biologist expressed his doubt that this could be a fin whale. I took several close up photos of the whale. If needed, I can post here.. let me know how I can post images..

    Posted 8 years ago #
  2. Anonymous


    Posted 8 years ago #

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