Posted by: LuCHy | 15/04/2012

The Killer Whale

The killer whale is a kind of cetacean belonging to the family of the oceanic dolphins which lives in all the oceans in the planet, from the Arctic and Antarctic regions to the tropical seas. This cetacean has got a robust and hydrodynamic complexion. They have a dual distinctive characteristic, a dorsal very long fin that can measure up to 1,8 m in males and the fact that they present a white and black coloration that is distributed in a particular way, which is own of every individual and allows to distinguish one from the others. The killer whale has a sexual marked dimorphism; females are smaller than males and have a shorter dorsal fin. An adult male can reach 5,5 t of weight and up to 9 m of length, while a female is normally about 7,7 m of length and weighs less than 4 t.

The individuals of this species form complex social structures organized in  matrilineal groups (descent defined by the mother line); to facilitate the socialization they use a sophisticated method of communication. Several types of killer whale have been identified in both hemispheres north and south, which have genetic, morphologic, behavioral and food differences so notable that some people have even proposed to consider them as different species. The killer whale has a combination of force, speed and intelligence that turns her into a very versatile predator; in fact,  being at the top of the food chain and hot having natural enemies it turns out to be the super predator of the oceans. Its diet is very varied and, depending on the type of killer whale, it feeds on fish, squids and marine mammals such as sea lions, seals, walruses and even large whales.

It is distributed all over the oceans in the world, from the waters of the Arctic and Antarctic up to the tropical seas; nevertheless, it prefers lukewarm and cold waters, and the areas near to the coast. It is a migratory species, some groups move up to thousands of kilometres, even crossing both hemispheres. All the threats for these animals are dependent on the action of man: the secondary pollution of pesticides, the noise produced by elements and acoustic devices, the deterioration of their habitat, the accidental captures during fishing operations and hunt. From antiquity, in the western culture it has been considered to be a fierce and dangerous animal. This image started changing from the decade of the 1960s, when it was observed that the first animals in captivity were behaving docile way and were not trying to attack human beings. Few assaults have been registered to human beings on the part of individuals in the wild, without any death. Nevertheless, the specimens in captivity, probably due to the stress that this situation causes, have caused some victims who have recovered.

You can find more information about killer whales at Wikipedia and Animal Facts.


%d bloggers like this: