Killer whale trivia
Orcas, whose English name is killer whale, are not whales but actually the largest member of the dolphin family.
And they exhibit the common characteristics of relatively high intelligence and high communication skills among fish.
Although killer whales are known for their distinctive black and white appearance, they actually vary in colour, with some having a light grey ‘saddle spot’ behind their dorsal fin.
Group hunting Advanced group living
Killer whales also exhibit intergenerational learning and cultural traditions. For example, unique behaviours such as the ‘carousel feeding’ of herring, a technique in which the fish is driven into a compact ball by releasing bubbles and flashing its white underbody, and then startling it with a powerful tail fin. It can be quite brutal in practice.
Another technique involves members of the herd working together to create waves that knock seals and other animals off the ice floes. They are strong enough on their own, but are particularly adept at co-ordinated hunting styles.
Group hunting by killer whales. More powerful than the Jaws film.
They live in matriarchal groups. These herds are part of larger clans or communities. Their social structure is complex and membership of a herd lasts a lifetime.
They do not have a human-like marriage system. Females usually mate with males from different herds to prevent inbreeding. Males and females do not pair up for long periods of time.
Interestingly, different populations of killer whales, known as ‘ecotypes’, have evolved unique traits and behaviours over thousands of years, ranging from variations in size, colour patterns and fin shape to differences in diet, vocalisation and social structure.
Their vocalisations, consisting of clicks, whistles and pulses, are also specific to particular groups and form a ‘dialect’ that is passed down from generation to generation.
Q.What is the orca’s favourite food? A. All-you-can-eat
Their diet is diverse. They are in some ways fearsome, eating all fish and cute seals, as well as giant whales and even the closely related dolphins. Herds may specialise in the capture of certain marine mammals.
As such, they are of course the apex predator in the marine ecosystem. Their only natural enemies are humans, whom they encounter extremely rarely.
They are one of the most widespread mammals on the planet, inhabiting oceans from the Arctic to the Antarctic. This means that they can live from icy polar waters to tropical seas.
Advanced intelligence of killer whales
Female killer whales can live for many years past menopause, like us humans, which is a little unusual among animals. This is thought to play an important role in the survival and success of the family by sharing knowledge and guiding the group to food sources. It is also a sign of a highly intelligent animal.
Killer whales’ large brains and powerful problem-solving skills have been demonstrated in a variety of ways, such as deliberately running aground to catch seals on land before wriggling back underwater.
They are known to imitate human speech. Some captive individuals mimic words such as ‘hello’ and ‘bye-bye’.
Miscellaneous
Killer whales are active both day and night, with no strict diurnal or nocturnal pattern. Their activity may depend on the availability of prey and social interactions within the group.
It is generally believed that the current population decline is mainly due to human activity. Factors include pollution such as PCBs accumulated in the body, depletion of prey species due to overfishing, and noise pollution that interferes with echolocation capabilities.
There are a few documented cases of killer whales harming humans, but these are extremely rare. Many cases involve captive animals, as there are few opportunities for contact in the first place. Killer whales in the wild are also not generally considered a threat to humans.
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