Updated July 27, 2021 at 4:10 PM ET
When you think of Australia, it's hard to not immediately think of its eclectic animals. You know the ones: jacked kangaroos, tarantulas, the inland taipan. But one bird that deserves more attention is the cockatoo.
"They're quite raucous...They're flamboyant. There's nothing quiet about them," Richard Major, a bird ecologist, says. "They're really in your face and they're just full of life and mischief."
Major has been studying Australian birds for almost 40 years. A few years back, he began noticing something peculiar in Sydney: cockatoos that were eating out of someone's open trash bin.
"I wasn't really expecting cockatoos to be rubbish bin feeders," he said. "They're not something like ibis or crows that are scavengers. These are good, self-respecting seed-eaters — or at least plant-eaters."
Major was a bit taken aback by the meal choice, but brushed the encounter off. Then, he saw something even stranger.
"The thing that really got me was when I saw a cockatoo fly up from a rubbish bin, sit on a electricity wire, holding a chicken drumstick in its foot," he says, explaining that a cockatoo can perch on one leg and hold its food in another. "Here it was, just munching on a drumstick, and I thought, 'Oh god, this is verging on cannibalism.' Certainly once cockatoos start eating meat, we're done for."
He'd just assumed that those bins were already open and overflowing — nothing clever about that. But Major later began observing several of the birds actually opening the bins themselves, and now he was intrigued. If this behavior spreads, he thought, "There'll be cockatoos opening bins all over the place and they'll have this endless supply of rubbish." A cockatoo smorgasbord.
Assembling the bird brain trust
Curious to explore this, Major sent a video to some colleagues at the Max Planck Institute of Animal Behavior. He wasn't sure if they'd be as into it as he was, but to his joy, the scientists were amazed.
"The amazing thing is just that they really found a way to access another resource," Barbara Klump, a behavioral ecologist at the institute, says.
Cockatoos typically live in woodland environments and eat a variety of seeds, nuts and fruits. In the last few decades, Major says their populations in urban environments have increased. Klump stresses that, even though urban cockatoos have access to a lot of resources and a greater variety of food options, they're not all freely available, which is what makes this behavior what she calls "an innovation."
The cockatoos make it look easy, but as someone who has studied animal behavior for years, Klump could see that it was actually a really complex motor action. First, they pry the bin open, hold the lid with their beaks, walk along the rim, and then flip it over — and she noticed subtle differences in each of these stages between different birds. Klump's interest was piqued.
"It opens up lots of questions," she says, "of 'How do they actually acquire this skill to follow this sequence?' and 'What are the differences, maybe, between individuals or also between different areas where the birds opened up in?"
Discovering cockatoo subcultures
A team of scientists — including John Martin, Sonja Wild, Jana K. Hörsch and Lucy Aplin — joined Klump and Major to figure out what was going on with these clever cockatoos. They started by sending surveys out to different suburbs in Sydney to ask people if they had noticed the big white parrots opening up their trash bins and, if they had, when they first saw it. The survey results showed that over two years, the number of trash-raiding cockatoo sightings had increased from just three suburbs to 44, indicating that the birds were learning from each other. A culture of trash can break-ins was radiating out from the birds who first figured it out.
For the next part of their study, the team wanted to get a closer look at the birds themselves. Normally, this kind of behavioral analysis involves capturing the animals, but Klump had a different way. She spent weeks going to parks around Sydney and feeding seeds to the birds to get them close, then marking hundreds of them with non-toxic paint so they could be easily identified later when the team took videos.
By studying these videos and tracking the birds, they found that cockatoos in different regions had their own ways of opening the lids. The differences were small — opening the bins with their feet versus their beaks, opening the left side or the right, walking the lid back via shuffled feet or one foot in front of the other — but consistent. Major says this is a demonstration that the birds are learning from each other, creating their own subcultures.
"[This] may sound trivial, but when you put these together, it is a different way of opening a bin that demonstrates that is a different behavior," he says. "And it's a different culture because birds that are in the same social group have a similar behavioral method of opening a bin, whereas birds that are further apart are more different in their opening style."
Man vs. bird: an evolutionary arms race
Klump and Major are going to keep studying these cockatoos for a while longer. Unsurprisingly, many Australians aren't thrilled to have their trash ravaged by the cockatoos, who are not particularly neat when they're feasting. And just as the cockatoos adapted to their urban environment to find a new food source, the humans are adapting, too. Major says in some suburbs, humans have invented their own anti-cockatoo systems to stop the birds from opening the bins; there's even a commercial bin clip now that engages a hook to stop the lid from getting lifted.
So cockatoos adapt to the humans, who then adapt to the cockatoos, who then adapt once again, and so on... In what Klump has called an evolutionary "arms race," it seems like Major is on Team Cockatoo. "I'd say generally the way people operate is, we only ever tackle a problem once it's a problem," he says. "So I think we will be slower learners than the cockatoos, and I think [this behavior] will spread a long way."
Despite these neighborly quarrels, as a long-time bird-lover and scholar, Major hopes the beauty of the cockatoo doesn't get overlooked.
"I just like to accentuate that I think we're really very lucky to have such charismatic birds sharing our cities. And it's really a credit to them that they're one native species that's adapted so well to human domination of the environment," he says. "I just hope our research will help us learn to live with them as well as they're learning to live with us."
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