Killer whale

The killer whale (Orcinus orca), also referred to as the orca whale or orca, and less commonly as the blackfish or grampus, is a toothed whale belonging to the oceanic dolphin family. Killer whales are found in all oceans, from the frigid Arctic and Antarctic regions to tropical seas. Killer whales as a species have a diverse diet, although individual populations often specialize in particular types of prey. Some feed exclusively on fish, while others hunt marine mammals like pinnipeds, and even large whales. Killer whales are regarded as apex predators, lacking natural predators.

Killer whales are highly social; some populations are composed of matrilineal family groups which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviors, which are often specific to a particular group and passed across generations, have been described as manifestations of culture.

Wild killer whales are not considered a threat to humans, but there have been cases of captive orcas killing or injuring their handlers at marine theme parks. Killer whales feature strongly in the mythologies of indigenous cultures, with their reputation ranging from being the souls of humans to merciless killers.

Killer whale
  • Size

    Killer whales are the largest extant members of the dolphin family. Males typically range from 7 to 9 metres (23 to 30 ft) long and weigh in excess of 6 tonnes (5.9 long tons; 6.6 short tons). Females are smaller, generally ranging from 6 to 8 m (20 to 26 ft) and weighing about 3 to 4 tonnes (3.0 to 3.9 long tons; 3.3 to 4.4 short tons). The largest male killer whale on record was 9.8 m (32 ft), weighing over 10 tonnes (9.8 long tons; 11 short tons), while the largest female was 8.5 m (28 ft), weighing 7.5 tonnes (7.4 long tons; 8.3 short tons). Calves at birth weigh about 180 kg (400 lb) and are about 2.4 m (7.9 ft) long.

  • Feeding

    Killer whales are apex predators, meaning that they themselves have no natural predators. They are sometimes called the wolves of the sea, because they hunt in groups like wolf packs. Killer whales hunt varied prey including fish, cephalopods, mammals, sea birds and sea turtles. However, different populations or species tend to specialize and some can have a dramatic impact on certain prey species. Those that feed on mammals may not even recognize fish as food. This specialization in diet and hunting, combined with small differences in markings, suggest that they might be different species, rather than populations.

  • Life History

    Female killer whales mature at around age 15. They then have periods of polyestrous cycling with noncycling periods of between three and 16 months. Gestation varies from 15 to 18 months.
    To avoid inbreeding, males mate with females from other pods. Mothers calve, with usually a single offspring, about once every five years. In resident pods, births occur at any time of year, although winter is the most common.Weaning begins at about 12 months and completes by the age of two. Females breed until age 40, meaning on average they raise five offspring. The lifespans of wild females average 50 years, with a maximum of 80–90 years.

  • Behavior

    Day-to-day killer whale behavior generally consists of foraging, travelling, resting and socializing. Killer whales are frequently active at the surface, engaging in acrobatic behaviors such as breaching, spyhopping, and tail-slapping. These activities may have a variety of purposes, such as courtship, communication, dislodging parasites, or play. Spyhopping, a behaviour in which a whale holds its head above water, helps the animal view its surroundings.

    Resident killer whales swim with porpoises, other dolphins, seals, and sea lions, which are common prey for transient killer whales.