Sulfur-crested Cockatoos Are Now Learning From Each Other How To Open Trash Cans, According To New Study (Video)

Often regarded as highly intelligent parrot species, sulfur-crested cockatoos are now learning from each other how to open trash cans in order to scavenge food across Sydney, according to a new study published in the journal Science.

Researchers in Australia, with the help of members of the public have documented cockatoos learning the bin-diving behaviour through what they called social interactions, with reported sightings of the behaviour growing across Sydney in recent years.

In the new study, members of the public were asked to report sightings of cockatoos opening bin lids in Australia. Before 2018, bin foraging was sighted in only three suburbs in greater Sydney and Wollongong: Barden Ridge, Helensburgh and Sutherland. But by the end of 2019, researchers noted that the ability of some cockatoos to open bins had spread widely, with sightings reported in 44 suburbs.

In the video below, the birds can be seen grasping bin lids with their beaks, pry them open, then shuffle far enough along the bins’ edge that the lids fall backward — revealing edible trash treasures inside.

According to Dr Barbara Klump of the Max Planck Institute of Animal Behavior in Germany, who was one of the study’s lead authors, the behaviour spread more quickly to neighbouring areas than to suburbs farther away, suggesting the cockatoos were learning by observing others, rather than figuring out how to open bins by themselves.

Klump said: “It’s not popping up randomly in those 44 suburbs at the same time, but it’s following … the geographic layout of the suburbs.”

Following the study, the researchers marked and observed 486 cockatoos. In direct observations, they found only around 10% of the birds, most of whom were male, were capable of opening the bins. The rest of the cockatoos waited until bins were opened to share in the spoils.

The process of a cockatoo swinging open a wheelie bin lid is “quite tricky both from a motor action and a physical strength perspective”, Klump said. “It’s a very complex and multi-step sequence that they have to learn.”

Klump hypothesises that more male cockatoos were able to successfully open the bins potentially because they are larger, or more dominant and “restricting access to the [food] resource”.

The study also found differences in the cockatoos’ bin-opening technique between different suburbs, arising from “local subcultures”.

“We found that if we looked, for example, at all the birds in Stanwell Park – even though some of them have individual differences – and if we compared them to birds in Sutherland … the difference [in technique] is greater than within each of those sites.”

The cockatoos also seemed to differentiate between red-lidded general waste bins and yellow-lidded recycling bins based on their colour. When observed, 88.8% of the time the birds opened the general waste bins.

The idea for the study arose a few years ago, when one of the co-authors, Dr Richard Major of the Australian Museum, noticed a sulfur-crested cockatoo opening a trash bin on his way to work.

The researchers don’t know for certain how the behaviour began, but co-author Dr John Martin of the Taronga Conservation Society said it may have originated from cockatoos scavenging in bins that were overfull or blown open on windy days.

“Those sorts of opportunistic foraging opportunities could have actually been a catalyst for birds to start exploring bins,” Martin said.

The researchers also noted one cockatoo in Narraweena, in northern Sydney, seemed to have spontaneously taught itself the behaviour in late 2018. “That one could not be explained by social learning because it was too far away [from other documented cases],” Klump said. “From that suburb to the surrounding suburbs, it again was acquired by observation.

“The interesting question is now whether it’s continuing to spread.”

Martin said there were reports of the behaviour in Victoria that they were planning to investigate. “We’d love to be receiving more information to confirm when and if this behaviour is occurring in other areas across Australia.”

The researchers are running the survey again and are seeking online responses from Australians on whether they have spotted cockatoo bin openings. “Having an answer that’s a ‘No, it doesn’t occur here’ is as important for this survey for us,” Martin said.

Researchers from Helsinki who studied the behaviour of more than 9,000 dogs covering 24 breeds found that Long-Haired Collies, like Rough Collie, Miniature Poodle, and Miniature Schnauzer are more likely than others to exhibit aggressive behaviour.

The study also revealed that small dogs are more likely to behave aggressively than mid-sized and large dogs, but due to their size, are often not seen as threatening and the bad behaviour therefore goes unaddressed.

Male dogs are also more aggressive than females and neutering them has no impact.

The researchers noted that Labradors and Golden Retrievers known for their docile temperament and gentle nature, are the least aggressive dog breeds.

Notable breeds such as Rottweilers, Dobermans and British Bulldogs were however not included in the list.

Although breed impacts aggression, dog owners experience has a greater role in aggressivness, with the first dogs of novice pet owners being more likely to behave aggressively.