The Orca (Killer Whale)
The orca (Orcinus orca), or killer whale, is the largest member of the oceanic dolphin family. They have been sighted by Society members on rare occasions off the coast at Bermagui.
Although they are not technically ‘whales’, dolphins and whales are closely related. Orcas were given the name ‘killer whale’ by ancient sailors who observed groups of orcas hunting and preying on larger whale species. We know that orcas are top predators, yes, but not the vicious ‘whale killers’ that the ancient mariners thought them to be. Orcas can live up to 80 years old in the wold, and weigh as much as 6 tons.
Orcas are generalist eaters, consuming fish, seals and sea lions, dolphins and porpoises, sharks and rays, large whales, cephalopods (octopods and squids), seabirds and more. However, some orcas specialise on specific prey, and it turns out orcas are picky eaters! Once they’ve learned what their family eats, they aren’t likely to switch diets. These marine mammals have many hunting techniques, and are often referred to as ‘wolves of the sea’. Killer whales live and hunt together in ‘pods’, or family groups, much like a pack of wolves. They are matriarchal, with the pods being led by the oldest female of the group.
Did you know?
Despite being called "killer whales," orcas are actually the largest member of the dolphin family. They are toothed whales and are known as the "largest dolphins on earth".
Orcas are very social and live in groups called pods, which are like big families. Each pod has its own unique sounds and, just like people, they have "dialects" or accents that help them talk to their family members and tell them apart from other pods.
Because orcas need to come to the surface to breathe, they cannot go into a deep sleep like humans do. Instead, they only let half of their brain sleep at a time, and they keep one eye open to watch for danger or to make sure they can breathe.
In 1987, a group of orcas was spotted wearing dead salmon on their heads like "hats" for a whole summer! Scientists aren't sure why, but it was likely just a fun "fad" or game.