Unlocking the language of killer whales
THE transient killer whale is not typically considered one of Australia's native ocean creatures, let alone one of Western Australia's, but 24 nautical miles off Bremer Bay in the Bremer Canyon, a population of between 50 and 100 orcas live mostly undisturbed.
The aggregation was discovered in 2005 and has since become the most popular location in the country for killer whale research.
Curtin University PhD candi- date Rebecca Wellard (pictured below) began studying marine mega fauna 10 years ago and two years ago she developed an interest in killer whales’ bioacoustics and communication.
She said since the discovery of the pod was so recent, there was a lot to learn about native WA killer whales.
“It is a frontier science, we're not sure where they're coming from or where they're going,” she said.
Ms Wellard's passive acoustics monitoring is a non-invasive hy- drophone over the side of the boat to help uncover how the whales interact while socialising, travelling and hunting.
She said findings could determine whether WA killer whales communicated in another 'language' to their northern counterparts.
“My study is into the acoustics and communication between the killer whales and to see if it's geographic,” Ms Wellard said.
In the Northern Hemisphere, where the species has been studied at a much greater level, pods have been known to develop their own dialects.
They communicate using burst-pulse sounds and whistles, and they echolocate using clicktrains.
Killer whales are the largest animal in the oceanic dolphin family.
They are an apex predator, meaning their only threat is humans.
An adult orca can measure up to 9.8m and live for about 80 years.
The oldest known killer whale 'Granny' is estimated to be 103years-old.
Ms Wellard said the mammals live together all their lives and calves do not leave their mother.
She said at the Bremer Canyon, a female orca nicknamed Split Tip, because of a tear in her dorsal fin, visited the boat every time she visited the region.
“They are extremely intelligent, they are interactive and inquisitive,” Ms Wellard said.
The acoustic study can be viewed at http://dx.plos.org/ 10.1371/journal.pone.0136535.