Scientific Name: Orcinus orca (Linnaeus, 1758)
Common Name: Killer whale or Orca.
Classification: Odontoceti (toothed whales), family Delphinidae
Subpopulation: Iberian killer whale
Physical notes: Smaller than other subpopulations, adult size between 5-6.5 meters. The colour is contrasting black and white, with an eye patch, a white belly that widens into a trident in the anal-genital area and the underside of the tail fin is white. The V-form grey area behind the dorsal fin is called “saddle patch”. Clear sexual dimorphism: Males present a much larger dorsal fin than females, exceeding 1.5 m of length.
Distribution and habitat use: Cosmopolitan species, present in all the oceans and most seas. The Iberian orca subpopulation migrates from the Strait of Gibraltar to the north during the summer, since it is where the tuna moves. In autumn they fan out from the north into deep water. During the winter they return to the area of the Strait of Gibraltar, where they remain until the end of spring, repeating the cycle. These movements are diffuse, not all the groups travel together but that they move progressively and will always depend on their prey, the Atlantic bluefin tuna.
Group size: Family social grouping of 2-30 individuals. Average pod size is 6 individuals.
Life span: Males between 30-60 years and females between 60-90 years.
Gestation period: 16-18 months. Calves are born with ca. 200cm and they reach maturity at 10-13 years. Juveniles are weaned after 18 months bur can spend 3 years with the mother.
Diet and Feeding: Top predator with a variety of feeding techniques and specialisation in a particular type of prey. The Iberian orcas feed mainly on Atlantic Bluefin Tuna (Thunnus thynnus). They can dive up to 1000 m and hold their breath up to 17 min.
Typical Behaviour: Can be very active at the surface, especially when socialising or after a successful hut. Often breaches, flipper slaps and lobtails. Frequently spyhops. Occasionally bow rides and is curious towards the boats.
Population status: No reliable global estimate, but likely minimum 50,000. From photo-identification studies between 1999-2011 it was identified 47 individuals from the Iberian subpopulation, from which at the end of 2011, only 39 individuals remained alive. The population trend is stable.
Threats: By-catch and entanglement, pollution, habitat degradation, prey depletion, increase marine traffic, underwater noise and disorganised whale watching tourist activities.
IUCN status: Globally is data deficient (2017). The Iberian subpopulation is critically endangered (2023).
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