Fin Whales occur worldwide, mainly, but not exclusively, in offshore waters. They are rare in the tropics, except in certain cool-water areas, such as off Peru.
North Atlantic:
In the North Atlantic, the Fin Whales range extends as far as Svalbard (Norway) in the northeast (but rarely far into the Barents Sea), to the Davis Strait and Baffin Bay (Canada and Denmark (Greenland)) in the northwest (but rarely into the inner Canadian Arctic), to the Canary Islands (Spain) in the southeast, and to the Antilles in the southwest (Rice 1998, Perry et al. 1999), but it is rare in the Caribbean and Gulf of Mexico (Ward et al. 2001). Their main summer range in the Northwest Atlantic extends from Cape Hatteras (39N) (US) northward (Anon. 2005a).
In former times, Fin Whales were caught year-round near the Straits of Gibraltar. While there may be some north-south migration between summer and winter, it does not necessarily involve the entire population, and North Atlantic Fin Whales may occur to some extent throughout the year in all of their range, as suggested by acoustic data (Clark 1995).
Mediterranean:
There is a resident subpopulation in the central and western Mediterranean which is genetically distinct from that of the North Atlantic (Brub et al. 1998). The species also occurs rarely in the eastern Mediterranean (Notarbartolo di Sciara et al. 2003).
North Pacific:
In the eastern North Pacific, Fin Whales occur year-round off the central and southern California coast (Anon. 2003). They occur in summer off the entire coast of western North America from California into the Gulf of Alaska. Fin Whales marked off California in winter were recaptured in summer by whaling operations along the entire coast, suggesting migration. Offshore, Fin Whales occur across the North Pacific north of 40N, at least from May to September in summer, with some tendency for a northward shift in distribution in high summer, when they also enter the Okhotsk Sea (Miyashita et al. 1995). They occur in the Bering Sea and some have been seen in the Chuckchi Sea, but rarely in the Beaufort Sea (Angliss and Outlaw 2004).
Fin Whales occur, albeit in small numbers, in Hawaiian waters in both summer and winter (Anon 2005b). They are rare or absent throughout the tropical North Pacific.
While there appears to be some migration, acoustic data suggests that overall there is no marked seasonality in distribution in the North Pacific (Watkins et al. 2000), in contrast to the traditional view of the Fin Whale as a migratory species.
Gulf of California:
The Fin Whales inhabiting the Gulf of California constitute a resident, genetically isolated subpopulation (Brub et al. 2002). Telemetry information has shown year-round residency in this area, with seasonal latitudinal movements (Urbn et al. 2005).
East China Sea:
Fin Whales in the East China Sea are generally recognized as being a distinct subpopulation from those of the North Pacific (Fujino 1960). Fin Whales appear to be rare today off the Korean peninsula and southern and central Japan, but large numbers were caught there in the 20th century (IWC 2006); it is not clear whether these animals were part of the East China Sea population or a separate grouping.
Southern Hemisphere:
While some Fin Whales do penetrate into the high Antarctic, along with Blue, Minke and Humpback Whales, the bulk of the Fin Whale summer distribution is in middle latitudes, mainly 40S-60S in the southern Indian and South Atlantic oceans, but 50-65S in the South Pacific, as evidenced by both sightings data and past catches (Miyashita et al. 1995, IWC 2006a).
The winter distribution is poorly known, but based on catch results Fin Whales were formerly common off southern Africa in winter and became scarce there following depletion of the species in the Southern Ocean, consistent with this being a wintering area of a migratory population (Best 2003). Catches were mainly off South Africa, but in the early 20th century there were also catches off Angola, Congo and Mozambique (Best 1994).
Recent sighting were made in the mid-latitude region (between 55S and 61S) by the IWC/SOWER (Southern Ocean Whale and Ecosystem Research Program). A high density area of Fin Whales was observed between 0E and 5E in the south of Bouvet Island (Ensor et al. 2007).
Large numbers of Fin Whales were caught off South Georgia in the past, but the species is not common there now (Moore et al. 1999). It is assumed that animals caught at South Georgia were migratory (Mackintosh 1965), but the location of their wintering grounds is unknown. Fin Whales are now rare in Brazilian waters, but there is virtually no information from the period before the depletion of the whales around South Georgia (Zerbini et al. 1997). A few were taken in a brief period of whaling in southern Brazil in the early 1960s.
Winter catches of Fin Whales off Chile, which also declined from the 1950s onwards in line with declining Southern Ocean stocks, are also suggestive of a wintering ground. Fin Whales were caught off Peru for only a few years from 1965 (prior to that the industry had focused on sperm whales), and catches petered out in the early 1970s.
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.
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.
North Atlantic:
In the North Atlantic, the Fin Whales range extends as far as Svalbard (Norway) in the northeast (but rarely far into the Barents Sea), to the Davis Strait and Baffin Bay (Canada and Denmark (Greenland)) in the northwest (but rarely into the inner Canadian Arctic), to the Canary Islands (Spain) in the southeast, and to the Antilles in the southwest (Rice 1998, Perry et al. 1999), but it is rare in the Caribbean and Gulf of Mexico (Ward et al. 2001). Their main summer range in the Northwest Atlantic extends from Cape Hatteras (39N) (US) northward (Anon. 2005a).
In former times, Fin Whales were caught year-round near the Straits of Gibraltar. While there may be some north-south migration between summer and winter, it does not necessarily involve the entire population, and North Atlantic Fin Whales may occur to some extent throughout the year in all of their range, as suggested by acoustic data (Clark 1995).
Mediterranean:
There is a resident subpopulation in the central and western Mediterranean which is genetically distinct from that of the North Atlantic (Brub et al. 1998). The species also occurs rarely in the eastern Mediterranean (Notarbartolo di Sciara et al. 2003).
North Pacific:
In the eastern North Pacific, Fin Whales occur year-round off the central and southern California coast (Anon. 2003). They occur in summer off the entire coast of western North America from California into the Gulf of Alaska. Fin Whales marked off California in winter were recaptured in summer by whaling operations along the entire coast, suggesting migration. Offshore, Fin Whales occur across the North Pacific north of 40N, at least from May to September in summer, with some tendency for a northward shift in distribution in high summer, when they also enter the Okhotsk Sea (Miyashita et al. 1995). They occur in the Bering Sea and some have been seen in the Chuckchi Sea, but rarely in the Beaufort Sea (Angliss and Outlaw 2004).
Fin Whales occur, albeit in small numbers, in Hawaiian waters in both summer and winter (Anon 2005b). They are rare or absent throughout the tropical North Pacific.
While there appears to be some migration, acoustic data suggests that overall there is no marked seasonality in distribution in the North Pacific (Watkins et al. 2000), in contrast to the traditional view of the Fin Whale as a migratory species.
Gulf of California:
The Fin Whales inhabiting the Gulf of California constitute a resident, genetically isolated subpopulation (Brub et al. 2002). Telemetry information has shown year-round residency in this area, with seasonal latitudinal movements (Urbn et al. 2005).
East China Sea:
Fin Whales in the East China Sea are generally recognized as being a distinct subpopulation from those of the North Pacific (Fujino 1960). Fin Whales appear to be rare today off the Korean peninsula and southern and central Japan, but large numbers were caught there in the 20th century (IWC 2006); it is not clear whether these animals were part of the East China Sea population or a separate grouping.
Southern Hemisphere:
While some Fin Whales do penetrate into the high Antarctic, along with Blue, Minke and Humpback Whales, the bulk of the Fin Whale summer distribution is in middle latitudes, mainly 40S-60S in the southern Indian and South Atlantic oceans, but 50-65S in the South Pacific, as evidenced by both sightings data and past catches (Miyashita et al. 1995, IWC 2006a).
The winter distribution is poorly known, but based on catch results Fin Whales were formerly common off southern Africa in winter and became scarce there following depletion of the species in the Southern Ocean, consistent with this being a wintering area of a migratory population (Best 2003). Catches were mainly off South Africa, but in the early 20th century there were also catches off Angola, Congo and Mozambique (Best 1994).
Recent sighting were made in the mid-latitude region (between 55S and 61S) by the IWC/SOWER (Southern Ocean Whale and Ecosystem Research Program). A high density area of Fin Whales was observed between 0E and 5E in the south of Bouvet Island (Ensor et al. 2007).
Large numbers of Fin Whales were caught off South Georgia in the past, but the species is not common there now (Moore et al. 1999). It is assumed that animals caught at South Georgia were migratory (Mackintosh 1965), but the location of their wintering grounds is unknown. Fin Whales are now rare in Brazilian waters, but there is virtually no information from the period before the depletion of the whales around South Georgia (Zerbini et al. 1997). A few were taken in a brief period of whaling in southern Brazil in the early 1960s.
Winter catches of Fin Whales off Chile, which also declined from the 1950s onwards in line with declining Southern Ocean stocks, are also suggestive of a wintering ground. Fin Whales were caught off Peru for only a few years from 1965 (prior to that the industry had focused on sperm whales), and catches petered out in the early 1970s.
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.
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.
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.
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.
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