Whales - Species | Killer Whale

Killer Whale - Orcinus orca

The Killer Whale, also called the Orca, is the largest species of the dolphin family and its found in all oceans worldwide, from the freezing Arctic waters to warm and tropical seas. The name ‘Orca’ was originally used by the Romans in referring to this particular species of whale, as the term ‘orc’ described a large fish, whale or sea-monster. The English term ‘Killer Whale’ is more commonly used, however, this has changed over time, partly due to the desire to remove their reputation as ‘killers’.

These whales are very distinctive in appearance and are very unlikely to be confused with any other sea creature. They have a black back, white chest and sides, as well as a white patch above and behind the eye, however, Antarctic Orcas may have pale grey to nearly white backs. They have heavy, stocky bodies and a large dorsal fin, their pectoral fins being large and rounded but larger in males. Calves are born weighing about 180 kilograms, measuring 2,4 meters long, with a yellowish or orange tint which fades to white. Males tend to be 6 – 8 meters in length and weighing in excess of 6 tonnes. Females are generally smaller, ranging from 5 – 7 meters and weighing 4 – 5 tonnes. The Killer Whale’s large size and strength make them among the fastest marine mammals, Killer Whales often reaching speeds in excess of 56 kilometers per hour. Usually these whales are distinguished from each other by means of their individual scratches and tears on their bodies. The pattern of white or grey in their saddle patch also identifies each individual.

Females gain sexual maturity at around 15 years of age. Mothers bear a single offspring once every five years, with births occurring any time of the year but mostly in winter. The gestation period varies from fifteen to eighteen months with all pod members, even males of all ages, caring for the young. Females breed until the age of 40, therefore raising five offspring in their lifetime on average. Males generally do not live as long as females, averaging only 30 years of age.

These Killer Whales can be found in all oceans and most seas such as the Mediterranean and Arabian Seas. However, they prefer the cooler temperatures and polar regions. They are sometimes called ‘wolves of the sea’, as they hunt in packs like wolves, averaging on about 227 kilograms of food per day. They have been known to occasionally harass and kill porpoises and seals for no apparent reason. Marine mammal prey species include the seal, sea lion and fur seal, with walruses and sea otters being taken less frequently. Complex hunting strategies are used by these whales to trap their prey, even occasionally throwing seals in the air in order to stun and kill them. Often to avoid injury, they disable their prey before killing it and subsequently eating it.

In order to swim quickly, killer whales sometimes leap out of the water in a motion called porpoising. Their daily behaviour is generally divided into four activities, namely foraging, travelling, resting and socialising by means of breaching, spy-hopping and tail-slapping.

Although these whales are not an endangered species, some populations are considered threatened or endangered due to pollution, depletion of prey species, habitat loss and whaling. Killer whales are not considered a threat to humans.