How killer whales move around Australia now better understood, thanks to citizen science project
Killer whales are more common in WA, including at Bremer Bay, than along Australia’s south-east coast. (Supplied: David Donnelly)
Killer whales have long been a challenge for researchers, particularly off Australia’s south-eastern coast.
But over the past three decades, data on sightings collected by the public and logged by citizen science project Killer Whales Australia is helping to create a better understanding of the elusive apex predators.
The project, based at the Dolphin Research Institute in Hastings, Victoria, started in 1994 as the Southern Ocean Orca Database, with marine scientist David Donnelly taking the reins in 2000.
The team collaborates with universities and works with colleagues in Western Australia to create a nationwide understanding of how killer whales move around the country’s waters.
“I had a passion for marine mammals and followed that as a career option, just building knowledge as I went along,” Mr Donnelly said.
“Killer whales just didn’t have much attention at the time in terms of understanding them — how many are there and where are they?
“They are an apex predator so they are important to the environment and I just felt like there was a gap there that needed to be filled.
“I’m doing my best from day to day to try and help to fill that with collaboration with a lot of people, which is what it’s going to take to get to where we get a better understanding.”
Bent Tip
Mr Donnelly said the project relies almost entirely on citizen science gathered by the public.
He said the sightings helped to build a database to work out the “whys, whens and whos of killer whales along our coastline”.
“If we’re lucky enough to get photos with those reports, we’re able to build things like fin identification catalogues, which allows us to identify individual animals,” he said.
One animal that has popped up in waters around southern Australia for years is known as Bent Tip.
“Bent Tip is a whale we have known for quite a long time now — we think we might’ve known him since maybe 2013,” Mr Donnelly said.
“Now that he’s a mature animal he’s not going to change much more … so we’re going to see more and more of Bent Tip as he progresses through his life.
“More often than not now, if a killer whale pod is spotted anywhere in the south-east Australian region, we typically know who they are.
“That indicates to us that we’re starting to get to a bit of a threshold of how many animals actually transit through the coastal areas of this part of the world.”
Citizen scientists helping research
Isabella Reeves is a PhD candidate at Flinders University in Adelaide and is part of the Cetacean Research Centre, studying the genetics of killer whales in Australasia.
She said without the database information collected by citizen scientists, research on killer whales would not have got as far as it had.
“Within Australia, we wouldn’t actually understand a lot of the ecology and distribution without this citizen science data,” Ms Reeves said.
After a great white shark carcass washed up near Portland in Victoria’s south-west, researchers have used data from Killer Whales Australia to investigate whether orcas were responsible.
“There’s a lot of predation work going on at the moment about what they’re eating,” Ms Reeves said.
“Understanding the species they may be eating, when we don’t see them a lot, is actually super helpful, and of course we can’t be on the water everywhere up and down the east coast.
“We have to rely quite heavily on these dedicated citizen scientists that are actually making a difference in how we’re understanding these killer whales.”
More sighting data needed
While the data gathered by Killer Whales Australia has already proven vital for researchers, Mr Donnelly said there was still a need to grow, particularly along SA’s south-east coast.
“Along the south-west coast of Victoria, we get a lot of data from there, we’ve got a lot of very dedicated people who enjoy watching whales,” he said.
“The south-east of South Australia is a little bit different. We get much less, but what we do get is validation that some of the animals known from the east coast are venturing into south-east South Australia.
“Just a couple of weeks ago we had one animal that moved from Port MacDonnell [in SA] across to the east and [was] seen the following day in Portland [Victoria].
“Only with people reporting that information and a catalogue of fin identification images can we start to tell those stories.”
While Mr Donnelly has been leading the project for more than 20 years, he is excited to see a new generation of scientists emerging.
“I look forward to sitting in my retirement home reading about what my proteges are now doing with the data,” he said.
But before then, Mr Donnelly has one more goal in mind.
“On the list of things that I need to do in the next little while is to just try and locate some killer whales that I can view through my own camera lens,” he said.
“If it doesn’t happen, I think we still have this fantastic dataset that’s going to help to inform on what I think’s a very important marine species.”
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