Geographic Range
Fin whales, or fin-backed whales, are found in all major oceans and open seas. Some
populations are migratory, moving into colder waters during the spring and summer
months to feed. In autumn, they return to temperate or tropical oceans. Because of
the difference in seasons in the northern and southern hemisphere, northern and southern
populations of fin whales do not meet at the equator at the same time during the year.
Other populations are sedentary, staying in the same area throughout the year. Non-migratory
populations are found in the Mediterranean Sea and the Gulf of California.
In summer in the North Pacific Ocean, fin whales migrate to the Chukchi Sea, the Gulf
of Alaska, and coastal California. In the winter, they are found from California to
the Sea of Japan, East China and Yellow Seas, and into the Philippine Sea.
During the summer in the North Atlantic Ocean, fin whales are found from the North
American coast to Arctic waters around Greenland, Iceland, north Norway, and into
the Barents Sea. In the winter these fin whale populations are found from the ice
edge toward the Caribbean and the Gulf of Mexico and from southern Norway to Spain.
In the southern hemisphere, fin whales enter and leave the Antarctic throughout the
year. Larger and older whales tend to travel further south than younger ones.
- Biogeographic Regions
- arctic ocean
- indian ocean
- atlantic ocean
- pacific ocean
- mediterranean sea
- Other Geographic Terms
- cosmopolitan
Habitat
Fin whales inhabit the temperate and polar zones of all major oceans and open seas
and, less commonly, in tropical oceans and seas. They tend to live in coastal and
shelf waters but never in water less than 200 meters deep.
- Habitat Regions
- temperate
- tropical
- polar
- saltwater or marine
Physical Description
Fin whales are the second largest mammals, after
blue whales
. They grow to 20 meters in length and weigh approximately 70,000 kilograms. Size
varies geographically: southern hemisphere whales are roughly 20 meters long, while
northern and Arctic fin whales reach up to 25 meters in length. Sexual dimorphism
in fin whales is limited, with males and females reaching roughly the same size and
weight as adults. It is generally easy to distinguish fin whales by their long, lean
bodies, their brown-grey dorsal surface, and deep white undersides. Fin whales can
be distinguished from other whales by the medium-sized white patch on their lower,
right jaw. The base of the tail is raised, causing their back to have a distinctive
ridge. The white underside wraps around to their midsection laterally. The dorsal
fin is 50 cm in height, curved, and found relatively far back on the body. The head
is quite flat and represents about 1/5 of total body length. These whales have two
blowholes and a single, longitudinal ridge extends from the tip of the snout to the
beginning of the blowholes. Fin whales are able to expand their mouths and throats
during feeding because of the roughly 100 pleats that run from the bottom of their
bodies to their mouths. These pleats allow the mouth cavity to engulf water during
feeding. Fin whales are filter feeders, with between 350 and 400 baleen plates that
are used to catch very small to medium-sized aquatic life suspended in the water.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
Reproduction
Fin whales are seen in pairs during the breeding season and are believed to be monogamous.
There have been sightings of courtship behavior during the breeding season. A male
will chase a female while emitting a series of repetitive, low-frequency vocalizations,
similar to
humpback whale
songs. However, these songs are not as complex as those observed in
humpback whales
or
gray whales
. One study has shown that only males produce these low-frequency sounds. Low frequencies
are used because they travel well in water, attracting females from far away. This
is important because fin whales do not have specific mating grounds and must communicate
to find each other.
- Mating System
- monogamous
Both mating and calving occur in the late fall or winter when fin whales inhabit warmer
waters. Each female gives birth every 2 to 3 years, birthing one calf per pregnancy.
Although there have been reports of fin whales giving birth to multiple offspring,
it is rare and those offspring rarely survive. The gestation period is 11 to 11.5
months. The mother then undergoes a resting period of 5 or 6 months before mating
again. This resting period may extend to a year if the female fails to conceive during
the mating period.
Fin whale calves are born at an average length of 6 meters and weighing 3,500 to 3,600
kilograms. Calves are precocial at birth, able to swim immediately after. The age
of sexual maturity ranges in from 4 to 8 years. Male fin whales become sexually mature
at a body length of about 18.6 meters while females mature at a body length of 19.9
meters. Physical maturity does not occur until the whales have reached their full
length, after 22 to 25 years of age. The average length for a physically mature male
is 18.9 m and 20.1 m for females.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- viviparous
The mother nurses the infant for 6 to 7 months after it is born. Since the calf does
not have the ability to suckle, like land mammals, the mother must spray the milk
into the mouth of the baby by contracting the circular muscles at the base of the
nipple sinus. Feeding takes place at 8 to 10 minute intervals throughout the day.
At weaning the calf is usually 14 meters long, it then travels with its mother to
a polar feeding area where it learns to feed itself independent of its mother.
- Parental Investment
- precocial
-
pre-fertilization
- provisioning
-
protecting
- female
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- female
-
provisioning
Lifespan/Longevity
The typical lifespan of a fin whale is roughly 75 years but some there are reports
of fin whales that have lived in excess of 100 years.
Behavior
Fin whales are among the most sociable species of whales, they often congregate in
family groups of between 6 and 10 members. Occasionally fin whales form groups of
nearly 250 individuals near feeding grounds or during migration periods. Fin whales
are highly migratory; in spring and early summer they usually reside in colder feeding
waters, in fall and winter they return to warmer waters to mate. Fin whales have long
been noted for their extreme speed and are one of the fastest marine mammals, with
a cruising speed of nearly 23 mph and a “sprinting” speed of nearly 25 mph. Fin whales
can dive up to depths of roughly 250 m and stay underwater for nearly 15 minutes.
In addition, male fin whales often make extremely low frequency sounds that are among
the lowest sounds made by any animal.
Home Range
Home range sizes have not been established. Fin whales migrate over long distances
throughout the year.
Communication and Perception
Fin whales, like blue whales, communicate through vocalizations. Fin whales produce
low frequency sounds that range from 16 to 40 Hz, outside of the hearing range of
humans. They also produce 20 Hz pulses (both single and patterned pulses), ragged
low-frequency pluses and rumbles, and non-vocal sharp impulse sounds. Single frequencies
(non-patterned pulses) last between 1 and 2 minutes while patterned calling can last
for up to 15 minutes. The patterned pulses may be repeated for many days.
Higher frequency sounds have been recorded and are believed to be used for communications
between nearby fin whales and other pods. These high frequencies may communicate information
about local food availability. The 20 Hz single pulses help whales communicate with
both local and long distances members and patterned 20 Hz pulses are associated with
courtship displays.
A study done about the sound frequencies of fin whales suggest that whales use counter-calling
in order to get information about their surroundings. Counter-calling is when one
whale of a pod calls and another answers. The information conveyed by the time it
takes to answer as well as the echo of the answer is believed to hold a lot of important
information about the whale’s surroundings.
- Communication Channels
- acoustic
- Other Communication Modes
- choruses
- Perception Channels
- visual
- tactile
- acoustic
- ultrasound
- chemical
Food Habits
Fin whales primarily feed on plankton-sized animals including crustaceans, fish, and
squid. As filter feeders they passively consume food by filtering prey out of the
water that they swim through. Fin whales occasionally swim around schools of fish
to condense the school so that they increase their catch per dive.
- Primary Diet
-
carnivore
- piscivore
- eats non-insect arthropods
- eats other marine invertebrates
- planktivore
- Animal Foods
- fish
- aquatic crustaceans
- other marine invertebrates
- zooplankton
- Plant Foods
- phytoplankton
- Foraging Behavior
- filter-feeding
Predation
Adult fin whales have no natural predators. Populations have been heavily exploited
by humans who nearly hunted them to extinction in the early part of the 20th century.
Hunting exceeded nearly 10,000 whales per year in the 1950’s. Young fin whales may
be targeted by large predators, such as
killer whales
, although fin whales groups are likely to be successful in defending their young.
Ecosystem Roles
Fin whales have little pressure exerted on them by predatory animals and thus their
main contribution to the general ecosystem is to consume large amounts of plankton.
Their carcasses also support communities of benthic animals as they fall to the ocean
floor and are consumed. As do other large whales, fin whales also host large communities
of parasites, such as barnacles, lice, and worms.
Economic Importance for Humans: Positive
Historically, fin whales were hunted extensively for their oil and blubber, as well
as their baleen. Aboriginal peoples have hunted fin whales for centuries and all parts
of the whale were integral in their lives as a source of food, fuel, and building
materials. Large-scale hunting efforts peaked in the 1950’s, as nearly 10,000 whales
were killed every year.
- Positive Impacts
- food
- body parts are source of valuable material
- source of medicine or drug
- research and education
Economic Importance for Humans: Negative
Conservation Status
Overhunting is responsible for low population numbers of fin whales currently. With
the invention and use of modern whaling technology, fin whale populations were depleted
due to hunting. In addition, fin whales are injured or killed in vessel collisions.
This is especially true in the Mediterranean Sea where collisions are a significant
source of fin whale mortality. Between 2000 and 2004, 5 fatal collisions with vessels
were recorded off the east coast of the United States. Fishing gear also kills fin
whales; entanglement results in at least one death per year. Fishing accidents have
killed 4 fin whales in the years 2000 to 2004. Finally, a study done on whale calls
shows that human sound can prevent mating. Since the whales use low frequency sounds
to call to females, human interruption through sound waves, such as military sonar
and seismic surveys can disrupt the signal sent to the females. This potentially can
result in mates not meeting and a reduction in birth rates in populations.
In order to help populations of fin whales recover worldwide, the International Whaling
Commission has set a zero limit for fin whale catches in the North Pacific and southern
hemisphere. The catch limit was passed in 1976 and continues be law today. Hunting
stopped in the North Atlantic in 1990. There are some exceptions to the commission’s
limitation, a limited number of whales are allowed to be caught and killed by aboriginal
natives in Greenland.
Commercial catches resumed in Iceland in 2006 and a Japanese fleet began catching
fin whales for "scientific" purposes in 2005.
Additional Links
Contributors
Prashanth Mahalingam (author), University of Michigan-Ann Arbor, Maya Silberstein (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor, Tanya Dewey (editor), Animal Diversity Web.
- Arctic Ocean
-
the body of water between Europe, Asia, and North America which occurs mostly north of the Arctic circle.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- Atlantic Ocean
-
the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- Pacific Ocean
-
body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- cosmopolitan
-
having a worldwide distribution. Found on all continents (except maybe Antarctica) and in all biogeographic provinces; or in all the major oceans (Atlantic, Indian, and Pacific.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- polar
-
the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.
- saltwater or marine
-
mainly lives in oceans, seas, or other bodies of salt water.
- pelagic
-
An aquatic biome consisting of the open ocean, far from land, does not include sea bottom (benthic zone).
- coastal
-
the nearshore aquatic habitats near a coast, or shoreline.
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- monogamous
-
Having one mate at a time.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- fertilization
-
union of egg and spermatozoan
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- young precocial
-
young are relatively well-developed when born
- natatorial
-
specialized for swimming
- diurnal
-
- active during the day, 2. lasting for one day.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- migratory
-
makes seasonal movements between breeding and wintering grounds
- social
-
associates with others of its species; forms social groups.
- acoustic
-
uses sound to communicate
- choruses
-
to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- ultrasound
-
uses sound above the range of human hearing for either navigation or communication or both
- chemical
-
uses smells or other chemicals to communicate
- zooplankton
-
animal constituent of plankton; mainly small crustaceans and fish larvae. (Compare to phytoplankton.)
- phytoplankton
-
photosynthetic or plant constituent of plankton; mainly unicellular algae. (Compare to zooplankton.)
- filter-feeding
-
a method of feeding where small food particles are filtered from the surrounding water by various mechanisms. Used mainly by aquatic invertebrates, especially plankton, but also by baleen whales.
- food
-
A substance that provides both nutrients and energy to a living thing.
- drug
-
a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease
- carnivore
-
an animal that mainly eats meat
- piscivore
-
an animal that mainly eats fish
- planktivore
-
an animal that mainly eats plankton
References
Croll, D., C. Clark, A. Acevedo, B. Tershy, S. Flores, J. Gedamke, J. Urban. 2002. Only Male Fin Whales Sing Loud Songs. Nature , 117: 809. Accessed April 09, 209 at http://polymer.bu.edu/hes/articles/aabmsss02.pdf .
Gambell, R. 1985. Fin Whale, Balaenoptera physalus. Pp. 171-192 in Handbook of Marine Mammals , Vol. 3, first Edition. San Diego, CA: Academic Press Inc..
Jefferson, T., S. Leatherwood, M. Webber. 1994. Marine Mammals of the World . Rome, Italy: Food and Agriculture Organization of the United Nations.
McDonlad, M., J. Hildebrand, S. Webb. 1995. Blue and Fin Whales Observed on Seafloor Array in the Northeast Pacific. Journal of the Acoustical Society of America , 98/2: 712-721.
Nowak, R. 1991. Balaenopteridae: Roquals. Pp. 969-1044 in Walker's Mammals of the World , Vol. 2, Fifth Edition. Baltimore and London: The John Hopkins University Press.
Reeves, R., B. Stewart, P. Clapham, J. Powell. 2002. Sea Mammals of the World . London: A&C Black.
Sokolov, V., V. Arsen'ev. 1984. Baleen Whales . Moscow: Nauka Publishers.
Tinker, S. 1988. Whales Of The World . Honolulu, Hawaii: Bess Press Inc..
2008. "Balaenoptera physalus" (On-line). ICUN 2008 Red List. Accessed April 02, 2009 at http://www.iucnredlist.org/details/2478 .
2006. "Finback Whales, Bioacoustics Research Program" (On-line). Cornell Lab of Ornithology. Accessed April 09, 209 at http://www.birds.cornell.edu/brp/listen-to-project-sounds/fin-whales .