[ad_1]
It’s rubbish day—the best day of the week for Sulphur-crested Cockatoos in southern Sydney. Over the past decade, Australia’s native parrots have learned, and taught each other, how to open litter box lids. It takes a bit of effort, but by stretching their legs, elongating their necks, and walking tightly around the edge of the can, cockatoos can successfully use their beaks to open the hinged lids. common in the suburbs of Sydney.
Now, however, there are some problems. A garbage can owner put a brick in the lid to keep out the cockatoos. But in the end it was no sweat for this bird. Standing on the edge of the trash can, he pushed the brick with his beak until it fell over the edge. Then he put the lid back on and reached in, throwing out the trash to find last night’s leftovers: bread and pizza. When he was full, he hopped next to the trash can.
Scientists first documented the clever behavior of cockatoos eight years ago when Richard Major, an ornithologist at the Australian Museum Research Institute in Sydney, filmed a cockatoo opening a bin and sharing it with colleagues. . Fascinated, scientists wanted to know how cockatoos learned this new trick. Publishing their findings in Science in 2021, they showed that Sulphur-crested Cockatoos, native to the forests of eastern and northern Australia, performed this skill not just once but many times. Geographically separated cockatoo populations have different methods of opening the bin; when one bird learns how to flip the lid, other birds in the area watch and learn.
This week, at Current Biology, a team published a follow-up study focusing on the human side of the equation. Researchers have documented more than 50 strategies which people employ to hide cockatoos in garbage cans. They suggest that the conflict may be the start of an “innovation arms race,” in which humans and cockatoos develop more ingenious ways of outsmarting each other to control access to resources. garbage can “For some of the protections, the cockatoos actually learn how to defeat them, and then people come up with better, more effective methods,” said lead author Barbara Klump, a behavioral ecologist at the Max Planck Institute of Animal Behavior. “People are really socially learning from other people, especially their neighbors, about how to protect trash.”
While the birds are beautiful, they have become undesirable pests in neighborhoods. “The homeowners don’t want it [the cockatoos] because they have to go and clean the streets,” said co-author Damien Farine, a social evolutionary ecologist at the University of Zurich. In southern Sydney, people can’t just get new bins or close theirs. bins—the cans are custom-fitted to the model of the municipal garbage truck and the lids must open when the truck flips the cans over. So, to get rid of the pesky birds, the garbage owners started to try some defensive strategies of their own.
Klump decided to study their responses. The researchers visited four suburbs, documenting 3,283 bins, and surveyed a further 1,134 people from 401 suburbs. They found that, like cockatoos, people learn the best strategies from each other: 172 people protected their litter boxes and 64 percent used social information when choosing a strategy., such as placing stones and bricks on the lids, pushing shoes and sticks on the hinges to jam them, and tying ropes to prevent the lids from swinging open. Some have purchased and installed a sold commercially ($30 USD). Putting weight under the cover works best, says John Martin, an applied ecologist at Western Sydney University who participated in the research, because cockatoos aren’t as powerful as a garbage truck.
Researchers are not concerned about the effect of pawing trash on the health of the birds. Sulfur-crested Cockatoos are not considered a species of concern by the International Union for the Conservation of Nature, and human remains are not their only food source. The trash cans are emptied only once a week, so the birds mostly eat seeds and plants. However, cockatoos have found a way to exploit the human environment and “treat themselves once a week with fast food,” Martin said.
Researchers believe the conflict could be the start of an innovation arms race. In human warfare, arms races occur when each side tries to outgun the other’s weapons and defenses. Nature has arms races, too. When parasitic cuckoos lay their eggs in the nests of other host species, for example, the egg color and pattern laid down by both species tend to evolve as each attempts to surpass the other. The potential cockatoo arms race has a unique quality. “This is the first time that one of these arms races has been described, as far as we know, that also involved humans,” Farine said.
To be certain an arms race is taking place, researchers must first understand in more detail how cockatoos teach each other to open trash cans. New techniques for opening bins need to be learned in birds, not invented on the spot, to be considered an arms race. That’s the “last piece of the puzzle” to figure out, Klump said.
Antonio Osuna Mascaró, who studies tool use in cockatoos at the University of Veterinary Medicine, Vienna, was not involved in this study and is not yet convinced that this is a true weapon breed. Cockatoo social learning is less advanced than that of humans, he says, and birds may be learning these strategies individually. “Every time a cockatoo finds a solution to one of these problems it’s through individual innovation—that’s my bet.” He suggests that researchers investigate how cockatoos learn to open a more heavily armored bin.
Further study of human-wildlife conflict may turn up other instances of arms races. Martin hopes this study will inspire more research of this type. “I think there are a lot of examples out there that haven’t been investigated,” he said.
There may already be one in Toronto, said animal behaviorist Suzanne MacDonald at the University of Toronto, who was not involved in the new study. He said raccoons like to paw through the trash in his city, which has already deployed special anti-raccoon trash cans. Since humans are smarter than raccoons, he says it’s an arms race the city can win.
MacDonald seems to have more faith in Australia’s scrappy birds, which are known for being smart. As the trash fight escalates, he says, “I’m on team cockatoo.”
Comments are closed, but trackbacks and pingbacks are open.