Pseudorca crassidens


False killer whales are the only living species of their genus Pseudorca. Although they are found globally, little information is available on the species in the ASCOBANS Agreement Area due to few sightings.


Physical description and behaviour:

Individuals have a long slender body measuring 5 m to 6 m length when adults. Their body is black coloured apart from a grey area sometimes occurring on the side of their head. Their head is narrow and small and gradually leads to overhang the lower jaw. Their dorsal fin is tall and recurved and is situated a little after half of the back. They also have long flippers, that are narrow and tapered with a broad hump on the front margin near the middle of the flipper, which is a distinctive feature of the species.

False killer whales can form large pods and are fast active swimmers. When observed they frequently bow-ride next to vessels. They tend to inhabit deep waters far away from the coast and have been observed interacting with other cetacean species such as bottlenose dolphins in the Pacific (Stacey, Leatherwood and Baird, 1994). They feed on fish and squid and have been observed sharing food previously (Stacey, Leatherwood and Baird, 1994).


Distribution and abundance:

The species is found worldwide especially in deep sub-tropical and tropical seas and occasionally in warm temperate waters, even if they are rarely observed. In the ASCOBANS Agreement Area, false killer whales only occur occasionally in the Bay of Biscay and there has been a couple of sightings in the North Sea, northwest Scotland, northwest Ireland and in the Celtic and Irish Seas. A few strandings have been recorded in the United Kingdom between 1927 and 1935 and one in the Netherlands in 1935. There is currently no abundance estimate available for the Agreement Area.


IUCN Red List of Threatened Species™ Assessment

  • NT (Near Threatened) globally, last assessed in 2018
  • NA (Not Applicable) in European waters, last assessed in 2007



False killer whales are thought to be vulnerable to bycatch as they feed on fish targeted by fisheries, risking getting caught in the nets. They are also known to mass strand which could affect local populations in the area. The largest mass stranding known occurred in 1946 in Argentina, where 835 individuals stranded (Caillet-Bois, 1948).


Assessment information
CMS InstrumentsASCOBANS, ACCOBAMS, Western African Aquatic Mammals, Pacific Islands Cetaceans
IUCN StatusNear threatened

No pictures for Pseudorca crassidens

Common names
EnglishFalse Killer Whale
Scientific name Pseudorca crassidens
Other details
Additional notesUpdates have been made in August 2021 as per European Whales, Dolphins and Porpoises by Peter G. H. Evans (2020) unless stated otherwise.