Killer Whales or Orcas are the top ocean predators, in fact they are called `apex predators’ because they have no predators above them to treat them as prey.
However, these big and powerful toothed whales are so tame and seemingly friendly when they are trained to perform in Sea World and other marine theme parks, it is difficult to think of them as ruthless and savage ocean killers.
The theme parks and the popular film ‘Save Willie’ have given people a whole new perspective on the orca, demonstrating its intelligence and a gentler side altogether alien to the role it plays in the oceans of the world.
Orcinus orca, also known as ‘The Wolf of the Sea,’ because it hunts in packs when it attacks its prey of seals, sea lions and walruses and even the occasional whale, is indeed a formidable predator, which uses its keen intelligence and its ecolocation skills to hunt down and catch its food. Some orcas feed exclusively on fish but others prefer the hunting of other sea mammals, even minke whales and penguins, and documentary films have shown how efficient and organised they are, herding fish and seals into vulnerable groups and even surfing up onto beaches to catch unwary prey. But they are not considered a threat to humans, although there have been deaths among trainers and handlers at marine theme parks, some of which could have been accidental as the orca is such a huge and powerful creature while humans are comparatively frail and vulnerable. Orcas are beautiful creatures in their black and white livery, their backs a glossy black and their chins, sides and underparts blindingly white with white oval patches near their eyes. They are the largest members of the dolphin family, males reaching 20 to 26 feet long and weighing in excess of six tons, the largest on record being 32-feet long and weighing 11 tons. Females are smaller, the largest on record being 28-feet long and 8.3 tons in weight. The pectoral fins are large and round like paddles and give the animal tremendous manouevrability, and the dorsal fin is long and triangular and very prominent. Females live longer than males, with a lifespan of up to 80 to 90 years as against the male’s maximum of 50 to 60, although one male was recorded at 59 years old when he died in 2010. Captive orcas live shorter lives, although some have reached 30 or 40. Worldwide population figures are difficult to determine because of the orca’s wide-ranging wanderings, but 50,000 is regarded as an absolute minimum. They prey on about 30 species of fish, including salmon, herring and even smaller sharks like makos, threshers and smooth hammerheads. Their ‘carousel’ method of catching herrings is interesting, as they herd them into a tight ball by releasing bursts of bubbles or flashing their white undersides, then slap the ball with their tail flukes, killing or stunning the fish which are then easy prey.