False Killer Whale
The False Killer Whale is found in all oceans of the world, including the Mediterranean and Red Seas. It prefers mainly offshore waters in deep tropical, subtropical and warm temperate seas.
Classification: The False Killer Whale was first known from a skeleton from Lincolnshire, England, and Owen named it Phocaena crassidens. A mass stranding in 1860 proved its continued existence (something that had been in doubt) and after examining the animals, Danish zoologist Johannes Reinhardt amended the classification to Pseudorca crassidens, referring to this cetacean's resemblance to the Orca (Killer Whale). The specific name, crassidens, means 'thick-tooth', and is a reference to this species' robust teeth. This species is quite separate to the Orca.
Local Names: False Pilot Whale; Pseudorca.
Description: The False Killer Whale is a small and slim cetacean, with a tapering, rounded snout that overhangs the lower jaw, upon which there are between 8-11 pairs of teeth, matching the upper jaw. Above the mouthline, a crease trails from below the eye to the tip of the head. The dorsal is curved and located around halfway along the rounded body. The flippers have a broad hump on the leading edge which resembles a shoulder. The body colour is predominantly black, save for the odd faint grey marks on the head and throat. Males and females reach a maximum length of 5.96m and 5.1m respectively. Maximum weight in males is 2.2 tonnes; in females, 1.1 tonnes.
Recognition at sea: The False Killer Whale can be identified by their size and head shape; the latter and the shape of the dorsal are also useful in distinguishing them from Pilot Whales. Also, this is the only 'Blackfish' to bow-ride and swim rapidly at the surface.
Habitat: False Killer Whales tend to prefer warm temperate, subtropical and tropical waters, mainly in either semi-enclosed seas or in the open ocean away from land. Occasionally individuals have been spotted as far north as the northern UK, Norway and Alaska.
Food & Feeding: False Killer Whales prey mainly upon squid and large fish (such as tuna and dolphinfish), but have been known to attack groups of small cetaceans. This species has a bad reputation for taking bait from fishermen's lines.
Behaviour: The typical family unit contains between 10-50 individuals, but this cetacean is highly social and groups of several hundred are also common. A fast-swimming species, the False Killer Whale often gets excited, and porpoises (leaping clear of the water whilst swimming), bow-rides, and chases faster vessels. It has adapted well to captivity and is easily trained, showing much less aggression that the Pygmy Killer Whale. Mass strandings are common; in one case, over 800 individuals were found ashore.
Longevity: Unknown.
Estimated Current Population: Unknown, but considered rare.
The Influence of Man: Hundreds of False Killer Whales have recently been slaughted by Japanese fishermen who drove them ashore; not for food but because their yields of yellowtail have been decreasing and they blame this on cetaceans in the area. Accidental kills of this species (mainly by entrapment in fishing gear) is also common, and some individuals have been taken into captivity, where they have adapted well.
Source: CETACEA
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