Marine Ecosystems, Conservation and Education

The Real Orca AKA The “Killer Whale”

August 12, 2017

The Orca (Orcinus orca) or “Killer Whale” is one of the most recognisable marine mammals in the ocean due to its large size and distinct black and white colour pattern. Having been around for roughly 11 million years the Orca has developed some characteristics that might come as a surprise to some readers. The following are 5 facts about Orca Whales you may not have known.

The Orca Whale is Actually Not a Whale

Although orca Whales carry the term whale in their most common descriptions, they are actually part of the dolphin or cetacean family of marine mammals. Being the largest animal in the dolphin family, Orca have an average life span between 50 and 80 years, with some individuals living as long as 100 years in the wild. At full maturity and weighing up to 5400 kg a male Orca can grow to an average length of 6 to 8 meters, with the largest Orca on record having measured almost 10 meters in length, weighing in at an astounding 9000 kg, that’s as big as a school bus.

Orca Whales Are the Most Widely Distributed Mammals In the World

Orca whales can be found in all of the major oceans of the world, and although they have been recorded in the warm ocean waters located in and around the equator, they appear to prefer to cooler ocean waters of the higher latitude polar regions. Unlike other species who seem to follow a regular migration route every year, orca whales seem to travel according to the availability of food, and they are one of the few species that travel freely between the upper and lower hemispheres of the globe.

Orca Whales Have No Sense Of Smell

It is believed that orcas have no sense of smell due to the fact that they have no “smelling organs” or a lobe of the brain that is dedicated to the sense of smell. Instead orcas rely on their sight and hearing while hunting, migrating or communicating. Thought to have better hearing than cats and dogs, orca whales use their excellent sense of hearing to practice what is called echolocation to hunt and navigate through dark or turbulent ocean waters. This means that orca whales will produce a sound and then listen for echoes in order to determine the exact location and distance of other sea animals.

Orca Whales Sleep With One Eye Open

As with dolphins, orca whales do not completely go to sleep because of their need to go to the surface to breathe. Orca whales will ensure they stay awake by only sleeping with half of their brain at a time. If an orca is sleeping with its left eye open, then this means that the right side of the brain is asleep, and vice versa

Orca Whales Speak Orca

The sounds or vocalizations that orca whales use to communicate is thought to be one of the most complex language systems in the animal kingdom. They can produce different sounds using a compact tissue in the nasal region ranging from low-frequency pulses to high-pitched whistles. Researchers think that each orca has a “signature call” or name which is recognized by other members of their pod, and that orca whales can communicate with each other over distances of up to 50 km. Aside from communicating through sound and vocalizations, researchers believe orca whales also use touch and gestures such as fin slapping and head gestures to communicate with each other.