Fin Whale Facts
About the fin whale:
Fin whales are found in deep, offshore waters of all major oceans, primarily in temperate to polar latitudes, and less commonly in the tropics. They occur year-round in a wide range of latitudes and longitudes, but the density of individuals in any one area changes seasonally.
Fin whales are migratory, moving seasonally into and out of high-latitude feeding areas during spring and summer and returning to southerly, temperate waters for mating and calving during autumn and winter. The overall migration pattern is complex, and specific routes have not been documented. However, acoustic recordings from passive-listening hydrophone arrays indicate that a southward "flow pattern" occurs in the fall from the Labrador-Newfoundland region, past Bermuda, and into the West Indies.
Although reliable and recent estimates of fin whale abundance are available for large portions of the North Atlantic Ocean, this is not the case for most of the North Pacific Ocean nor for the Southern Oceans. The present status of populations in these ocean basins relative to their pre-whaling population size is uncertain.
For management purposes, fin whales in U.S. waters have been divided into four stocks:
Reliable estimates of current and historical abundance of fin whales in the entire Northeast Pacific are currently not available. While reliable estimates of the minimum population size and population trends are available for a portion of this area, much of the North Pacific range has not been surveyed.
A 2002 shipboard line-transect survey of the entire Hawaiian Islands EEZ resulted in an abundance estimate of 174 fin whales (Barlow 2003). As of the 2004 Hawaii stock assessment report, this was the best available abundance estimate for this stock.
The California/Oregon/Washington stock was estimated at 3,279 fin whales based on ship surveys in summer/autumn of 1996 (Barlow and Taylor 2001) and 2001 (Barlow 2003). The 2003 stock assessment report lists the minimum population of this stock at approximately 2,541 animals.
Although the full range of the Alaska (Northeast Pacific) stock of fin whales has not been surveyed, a rough estimate of the size of the population west of the Kenai Peninsula is 5,700 (as of the 2007 stock assessment report). This is a minimum estimate for the entire Alaska stock because it was estimated from surveys which covered only a small portion of the range of this stock.
The minimum population estimate for the Western North Atlantic fin whale stock is 1,678. There are insufficient data to determine trends for this population.
Fin whales feed mainly on krill but also eat schooling fish including herring, cod, mackerel, pollock, sardine, and capelin. Fish are eaten more often in winter.
The fin whale can dive for up to 20 minutes at a time, and to depths reaching 1800 feet. The fin whale is the fastest swimming of all the large whales and is sometimes referred to as the "greyhound of the seas." Fin whales can swim at up to 30 mph (48 kmh) in short bursts when alarmed and at up to 18 mph (30 kmh) when migrating and cruising. Fin whales do not typically exhibit breaching behaviors, although there are documented instances of a fin whale breaching completely out of the water, despite its 70 foot length. Imagine seeing that!
The reproductive habits of these whales remain largely unknown, however, females are thought to give birth only at 3-year intervals. Mating and calving occur from November to March in temperate waters. The gestation period is approximately 11 months and newborn fin whales are about 6.4 m in length and weigh 1.8 metric tons. The period of lactation lasts 6-7 months and after weaning the young whales are approximately 12.2 m long. Sexual maturity is reached at 6-12 years of age. As with other migratory baleen whales, northern and southern hemisphere populations do not interbreed due to asynchronous seasons.
Interesting Facts & History
There are two named subspecies of fin whale:
B. physalus physalus in the North Atlantic
There is also a population of fin whales in the North Pacific, which most experts consider a separate, unnamed subspecies. These populations rarely mix, if at all, and there are geographical stocks within these ocean basins. There may be resident groups of fin whales in some areas, such as the Gulf of California, the East China Sea, and the Mediterranean Sea.
Fin whales are found most often alone, but groups of 3-7 individuals are common, and association of larger numbers may occur in some areas at times. Because their powerful sounds can carry vast distances, fin whales may stay in touch with each other over long distances. The fin whales’ dive sequence is 5-8 blows approximately 70 seconds apart before a long dive. They rarely raise their flukes as they begin their dive, which can be as deep as 1,800 feet.
Like the other fast swimming whales the fin is generally free of external markings, scarring, callosities, and parasites. The head coloring is asymmetrical for some reason, even though the head is darkly colored, the lower right side of the jaw is always white. This coloration also extends to the baleen inside the mouth which is differently colored on each side.
Commercial whaling for this species ended in the North Pacific Ocean in 1976, in the Southern Ocean in 1976-77, and in the North Atlantic Ocean in 1987. Fin whales are still hunted in Greenland and subject to catch limits under the IWC "aboriginal subsistence whaling" scheme, and Japan includes them in their JARPAII (6-year plan to kill up to 50 fin whales per year).
Other current threats are collisions with vessels, entanglement in fishing gear, reduced prey abundance due to overfishing, habitat degradation, disturbance from low-frequency noise, and the possibility that illegal whaling or resumed legal whaling will cause removals at biologically unsustainable rates. Of all species of large whales, fin whales are most often reported as hit by vessels. Schooling fish constitute a large proportion of the fin whale's diet in many areas of the North Atlantic, so trends in fish populations, whether driven by fishery operations, human-caused environmental deterioration, or natural processes, may strongly affect the size and distribution of fin whale populations.
The Atlantic Large Whale Take Reduction Team was established to develop a plan to reduce the incidental serious injury and mortality of fin whales, right whales, humpback whales, and minke whales in the South Atlantic shark gillnet fishery, the Gulf of Maine and Mid-Atlantic lobster trap/pot fishery, the Mid-Atlantic gillnet fishery, and the Gulf of Maine sink gillnet fishery.
Sea Shepherd is leading the effort to defend and protect fin whales from the harpoons of the illegal Japanese whalers in the Antarctic.