False killer whale
Class : Mammalia
Order : Cetartiodactyla
Family : Delphinidae
Scientific name: Pseudorca crassidens
False killer whales are large members of the dolphin family. It is a rare, large and active whale. False killer whales have dark coloration except for some lighter patches near the throat and middle chest. It has a slightly grey or off-white ‘W’ on its chest, a large sickle –shaped dorsal fin and a unique flipper with a characteristic hump on the leading edge that is set very far forward on the body with a clear elbow. They have a long slender body, a small conical head with a rounded overhanging forehead and no beak. In males the tip of the upper jaw overhangs that of the lower jaw. Females reach lengths of 4.5 m, while males are almost 6 m. In adulthood, false killer whales can weigh approximately 700 kg. In addition to these size differences, male and female False Killer Whales may be distinguished by the position of the melon (the oily, fatty lump of tissue at the centre of the forehead). In males, the melon protrudes further forward than in the females. False killer whales’ breeding season lasts several months. Gestation periods range from 14 to 16 months and lactation occurs for one and a half to two years. False killer whales have low reproduction rates with calving intervals of approximately seven years. Maturity occurs at around 12 years of age and maximum longevity is 63 years.
It is an active swimmer known to feed on smaller cetaceans most notably bottlenose dolphins. It frequently swims with its mouth open, exposing its sharp teeth. False Killer Whales are highly gregarious, occurring in socially cohesive herds of about 20–50 animals, in which both sexes are equally represented.
False killer whales often “strand” themselves in large groups of 10-20 where they chase groups of seals or sea lions into the shallower waters and became stuck. They are one of the few large mammals that leap out of the water over the wake of the ship, which is a useful identification attribute.
It is recorded off the coast of Maharashtra , Kerala, Tamil Nadu and the Andaman & Nicobar Islands. False killer whales occur in the U.S. in Hawaii, along the entire West Coast, and from the Mid-Atlantic coastal states south. The species can also be found in all tropical and temperate oceans worldwide.
They prefer tropical to temperate offshore waters that are deeper than 3,300 feet (1000 m), but is also known to move into shallow water on occasion. They approach close to land only where the continental shelf is narrow, possibly attracted to zones of enhanced prey abundance along the continental slope.
As a top predator it primarily eats fish and cephalopods, they also have been known to attack small cetaceans, humpback whales, and sperm whales. They eat some large species of fish, such as mahi-mahi (dolphinfish), tunas and sailfish. At present due to large-scale reductions in many “prey” fish stocks world-wide, over-fishing and subsequent ecosystem changes; world-wide populations of false killer whales are unknown but could result in population declines.
IUCN Red List: Data Deficient