Killer whale: beautiful and brutal, with a toothy smile and killer instinct to match

Name: Killer whale (Orcinus orca)

Size: Length: adult female 7 metres, adult male 9 metres (2.5 metres at birth). Weight: 3-5.5 tonne (~150kg at birth).

Diet: Marine mammals – dolphins and other whale species, fish and squid.

Habitat/Range: Coastal Australian waters, Antarctic waters and global distribution

Conservation status: Listed as data deficient.

Superpower/fun fact: They hunt and eat prey several times their size.

Killer whales. Sometimes referred to as the ‘panda of the sea’, their pied markings are where the similarities end, as killer whales are as carnivorous as pandas are herbivorous. The largest dolphin species with its toothy grin is a smiling assassin. Killer by name and killer by nature.

Researchers that study killer whales usually group them according to how they look and what that eat. There are the ‘residents’ – those that stay in one place and eat fish – as they do in areas like coastal Canada. Others in Antarctica specialise in an avian diet of penguins, and then there are the ‘transients’ that we see in our coastal waters of Australia. The transient killer whales prefer a diet of their peers, that is other whales, such as beaked whales, blue whales and humpbacks. Spinner dolphins, giant squid and the oceanic sunfish are sometimes on the menu too.

---

Voting for Australian Mammal of the Year 2023 is now open!

More information about the voting process can be found here.

---

It may be a difficult fact to swallow that these mammals like to eat other mammals, but each year tourists flock to the small seaside town of Bremer Bay in Western Australia, for the privilege of seeing these killers in action. Some witness beaked whales being skinned alive, while others see the orchestrated hunt of a blue whale, the largest mammal on earth, killed in a coordinated fashion that would rival the Olympic synchronised swimming team. Likened to watching a lion chase down a gazelle on the Serengeti, human nature has us watching. It can be a conflicting experience, perhaps best observed with one eye open in awe, that is, if you’re lucky enough to have a front row seat watching the food chain and circle of life in action. Similarly, each winter in Ningaloo, further north on the WA coast, tourists may see a predation attempt. It is no coincidence that when the humpback whales migrate to calve, the killer whales are patrolling the coast for a kill.

Killer whales may be fierce predators, but they have a highly evolved social structure. They form pods with family members and these pods remain stable for decades. The pods are led by a female matriarch and the young stay with their mums (this includes the male offspring, giving a new meaning to ‘Mummy’s boy’ as these boys never leave!). It is thought that the pods have specific vocal dialects and its these differences in sounds that help prevent inbreeding. The females can live to almost 100 years.

Adult males have a dorsal fin that can be more than two metres high – from a distance you could mistake it for a sail of a yacht – and weigh more than an African elephant.

Beautiful and brutal, with a toothy smile and killer instinct to match, this mammal eater is worth your vote.