Humans and cockatoos are locked in an ‘arms race’ for trash

In Sydney, Australia, man and bird are in a fierce battle for the most precious resource: garbage. Over the past few years, a team of scientists has been studying the area’s Sulphur-crested Cockatoo parrots, which have learned — and even taught other parrots — how to steal trash cans. And in new research on Monday, the team says humans have now started devising their own methods to keep birds out, with varying degrees of success.

Researchers at the Max Planck Institute for Animal Behavior in Germany have long been interested in deciphering the inner workings of animals around the world. Last year they published a deep dive into the garbage flight habits of Sydney’s Sulphur-crested Cockatoos. They found that the practice appeared to be an example of animal culture: a learned behavior that spread from birds in three suburbs to all of southern Sydney. As the technique passed from neighborhood to neighborhood, local cockatoos developed slight variations in behavior, such as lifting the lid of the garbage can fully open or not – something that happens quite often in the human culture (think of how different local cultures produce their own varieties of cheese).

The researchers told Gizmodo last year that they next wanted to document the human side of this struggle. And that’s exactly what they did in their new journal, published Monday in the journal Current Biology.

“When we collected data for the original study describing the behavior of cockatoos opening trash cans, I saw that some people had put devices on their trash cans to protect them from cockatoos, and I was surprised by the variety of different measures people had come up with. . So I really wanted to investigate the human response to cockatoos,” lead author Barbara Klump, a behavioral ecologist at the Max Planck Institute, told Gizmodo in an e-mail. -mail.

To do this, they surveyed the inhabitants of the neighborhoods besieged by these birds. A major stumbling block to any potential cockatoo tricks is that trash cans are designed to open and spill their contents when lifted by the automated arm of garbage trucks, meaning they cannot be fully sealed. But that hasn’t stopped people from devising a variety of methods, like putting bricks and rocks on lids, attaching water bottles to lid handles with cable ties, or using sticks to block hinges. . There are now even commercially available locks that are supposed to unlock upon collection (one such product can be seen here).

Unfortunately for humans, cockatoos have learned to overcome some of the simplest measures. But as birds adapt, people develop counters right away. As the researchers put it, parrots and Sydneysiders seem to be engaged in something of an “arms race” for innovation, though Klump was reluctant to describe it as all-out war.

“When cockatoos learn to circumvent this protective measure (for example by pushing bricks so that they can then open the trash can), respondents in our survey reported that they increased the effectiveness of their protective measures (for example by securing something heavy to the lid, so it can’t be pushed back) What we found is that trash can protection (and types of protection) are grouped together geographically and people learn about them from their neighbors,” Klump said.

The whole saga could be a glimpse of the kind of increasingly common human-wildlife interactions we can expect as we continue to build our cities bigger and encroach on wildlife habitats, the researchers say. Some animals, like these parrots, can find new ways to adapt to our presence, but many others won’t. And sometimes these interactions can be harmful to humans, as with the emergence of new zoonotic infectious diseases.

What exactly happens next is anyone’s guess. “You could imagine it’s going to continue to escalate (i.e. cockatoos learn to defeat higher level protection types and people come up with even better devices to protect their bins) or it maybe one side will ‘win’ the arms race,” Klump said.

For their part, the team plans to continue studying the underlying learning mechanisms that led these cockatoos to become proficient litter pickers, and they hope to document just how adept they might become at solving the latest counter-attacks. measures to keep them away from their treasure trove of waste.