Short-Finned Pilot Whale
The Short-Finned Pilot Whale can be found in all tropical, subtropical and warm temperate oceans. Apart from following prey, it is not thought that Short-Finned Pilot Whales migrate.
Classification: John Gray of the British Museum named a pilot whale 'from the south seas' in 1846, using only skeletal material. He guessed that the species would have a large beak, and thus named it G. macrorhynchus - but he was proved incorrect. However, the name survived.
Local Names: Pothead Whale; Shortfin Pilot Whale; Pacific Pilot Whale.
Description: The Short-Finned Pilot Whale is a fairly stocky whale, with low, rounded dorsal fin that is set one-third of the way along the body (in the young, the dorsal is more triangular). The flippers are pointed and shorter than in the Long-Finned Pilot Whales, only extending for as much as 19% of the body length in adults. The forehead is bulbous, leading to a small mouth which has between 7-9 pairs of teeth in each jaw. The body colour is very dark brown or grey-black, with the young being a lighter grey. Stranded animals are normally very dark. There is a light grey or white patch in the shape of an anchor on the throat and chest. There is also a streak behind the eye and a saddle patch behind the dorsal, but both of these can be either very visible or barely noticeable. Males reach a maximum of 7.2m and females 5.1m in length, though the further north the stocks are, the smaller the whales become. Males are around 38% smaller, with females around 28%. The maximum body weight for southern stocks are 3.95 tonnes (males) and 1.4 tonnes (females).
Recognition at sea: The Short-Finned Pilot Whale is normally found in groups of either tens or hundreds. The shape of the dorsal and the bulbous head should be enough to distinguish this species from all others save for its closest relative, the Long-Finned Pilot Whale, and the only outward difference between these two is the size of the flippers.
Habitat: Short-Finned Pilot Whales prefer tropical, subtropical and warm temperate waters where the surface has a temperature of between 8-25º. They are mainly an oceanic species, though they will enter coastal and shallow waters in search of food. Since this is one of the cetaceans that are more commonly found stranded, it is assumed that they do not adapt well to shallow waters.
Food & Feeding: Short-Finned Pilot Whales mainly take squid and octopi, but when none are available they will take fish.
Behaviour: The typical family unit contains around 40 individuals, and occasionally numbers rise to the hundreds. Short-Finned Pilot Whales like to associate with other cetaceans. Although an extremely social species, Short-Finned Pilot Whales are not normally acrobatic, preferring to move slowly and 'log' at the surface. They vocalise with clicks and whistles.
Longevity: Between 40-65 years.
Estimated Current Population: Unknown, but thought to be common.
The Influence of Man: Short-Finned Pilot Whales were most often taken as practice by American whaling crews in the 1800s - 196 in 1881, and 843 between 1850-55, although the total number is probably in the thousands. Whaling off St Lucia and St Vincent in the 1960s and 1970s claimed 220-225 animals per year. Japan took around 320 per year during the early 1980s. A small number are taken by Canada, USA, and Peru every year through entrapment in fising gear. At least 140 have been taken for captive exhibits worldwide since 1963, but mortality rates are high - around half die every year.
Source: CETACEA
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