Common Name: Killer Whale
Transient orcas near Unimak Island, eastern Aleutian Islands, Alaska
Orcinus Orca range .
General Description: The largest of the dolphin family, the Killer Whale is robust but streamlined. The head is rounded, with no beak. The dorsal fin is very tall and conspicuous, sickle-like in females and immature males, but triangular and up to 1.8 m tall in large males. The flippers are very large and paddle-like.
The colour pattern is easily recognisable. It consists of clearly defined areas of shiny black and cream or white. Generally, it is black above, with a light grey patch behind the dorsal fin. Chin, throat, belly and undersides of the tail flukes are white. There is a white patch on each flank, connected to the white belly. There is also a white oval patch just above and behind each eye. In calves, the black areas are grayish and the white areas are tinged with buffy yellow for most of the first year.
Size: Adults, Killer Whale males are considerably larger than the females. They are about 9.5 m long and weigh up to 8 tons, whilst females are 7 to 8.5 m long and weigh 4 tons or more. Calves at birth, 2-2.4 m long.
Appearance At Sea: Extended family groups of Killer Whales live together and cooperate in hunting. A pod consists of 5-20 members, of which 20 per cent are adult males, another 20 per cent are calves, and the rest are females and immature males.
The breathing pattern involves a series of up to five short dives of 10-30 seconds each, followed by a longer dive of 1-4 minutes.
Killer Whales are usually approachable, as they are undisturbed by shipping. They might respond by sky hopping, which involves rising vertically so that the head and body – as far as the flippers– are above the surface.
With their size, appearance and reputation for ferocity, Killers are ‘glamorous’ species. Their exhibition in oceanaria, since the 1960s, where they can be easily trained to perform astonishing tricks, and in television programmes and films have kept alive public interest in them.
Found In: Killer Whales may be found in coastal as well as deeper waters. The diet of a Killer Whale is very diverse, including fish, squid, turtles, birds and dolphins. This animal is one of the only predators of large marine mammals, including the largest whales.
Records from India: One Killer Whale was stranded at Armada, in Gujarat in 1943. This was the only record from India for many years, though even earlier, it was believed that this species was found in Indian waters.
|1943||One specimen stranded at Armada, Baroda State.||De Silva, 1987|
|[?]||Skull from the Nicobar Islands in the Bombay Natural History Society.||De Silva, 1987|
|1976||Three animals sighted less than 8 km off Madras Harbour.||Miller, 1976, personal communication|
|12 April, 1983||One sighted north of the Andamans.||De Silva, 1987|
|April 2000||Solitary Killer Whale, possibly female of length 6–7 m, off the reefs of Agatti,
|Rohan Arthur, personal communication|
There are numerous sightings, strandings and other records of Killer Whales from Sri Lanka, Pakistan, the Seychelles, the Gulf of Aden, Djibouti and Somalia.
World Distribution: The Killer Whale is very cosmopolitan, occurring in all oceans, from the tropics to the polar regions.
Could Be Confused With: Killer Whales are unmistakable if adult males are present in a pod. However, if only females and young are present in the pod there is a possibility of confusion with Risso’s Dolphin Grampus griseus and the False Killer Whale Pseudorca crassidens. These two species differ from the Killer Whale Orcinus orca in the following respects:
|Species||Body||Head||Colour and Markings|
|Killer Whale||Heavy-bodied||Blunt round head||Glossy black body with white spot behind the eye|
|Risso’s Dolphin||More slender body||More tapered head||Grey or white with many visible scars|
|False Killer Whale||More slender body||More tapered head||Solid black with no visible markings|
Diagnostic Features: At sea, Tall dorsal fin, white spot behind eye.
Stranded Specimens:There are 10 to 12 pairs of large conical teeth in each jaw. The teeth are very strong and sharp, and interlock when the jaws close.