A few years ago, a Sydney scientist noticed a sulphur-crested cockatoo opening his wheelie bin. Not everyone would be happy, but Australian Museum ornithologist* Dr Richard Major was impressed by the ingenuity*. It’s quite a feat for a bird to grasp a bin lid with its beak, pry it open, then shuffle far enough along the bin’s edge that the lid falls backward — revealing edible trash treasures inside. Intrigued, Dr Major teamed up with researchers in Germany to study how many cockatoos learned this move.
In early 2018, they found from a survey of residents that birds in three Sydney suburbs had mastered the foraging trick. By the end of 2019, birds were lifting bins in 44 suburbs.
“From three suburbs to 44 in two years is a pretty rapid spread,” said Dr Major.
The researchers’ next question was whether the cockatoos had each figured out how to do this alone — or whether they copied the strategy from more experienced birds. And their research published in the journal Science concludes the birds mostly learned by watching their peers.
“That spread wasn’t just popping up randomly,” said Dr Major. “It started in southern suburbs and radiated outwards.”
Basically, it caught on like a hot dance move.
Scientists have noted other examples of social learning in birds. One classic case involves small birds called blue tits that learned to puncture foil lids of milk bottles in the United Kingdom, starting in the 1920s — a crafty move, though not as hard or as physically difficult as opening rubbish bins.
But observing a new “cultural trend” spreading in the wild — or suburbs — in real time gave the cockatoo researchers a special opportunity, said Dr Lucy Aplin, a cognitive* ecologist* at Max Planck Institute of Animal Behaviour in Germany and co-author of the study.
“This is a scientist’s dream,” she said.
During the summer of 2019, rubbish-removal day in suburban Sydney was the team’s research day. As garbage trucks rolled down their routes and people shoved bins to the kerb, Max Planck Institute behavioural ecologist Dr Barbara Klump drove around and stopped to record cockatoos landing on bins. Not all cockatoos succeeded in opening them, but she took around 160 videos of victories.
Studying the footage, Dr Klump realised the vast majority of birds opening bins were males, which tend to be larger than females. The birds that mastered the trick also tended to be dominant* in social hierarchies*.
“This suggests that if you’re more socially connected, you have more opportunities to observe and acquire new behaviour — and also to spread it,” she said.
Cockatoos are extremely outgoing, social birds that forage in small groups, roost in large ones, and are rarely seen alone in Sydney. While overall animal numbers have declined with the growth of Australian cities, these bold and flamboyant* birds have generally thrived*.
“In an unpredictable, rapidly changing environment with unpredictable food sources, opportunistic* animals thrive,” said Dr Isabelle Laumer, a behavioural researcher at the University of California, Los Angeles, who was not involved in the research.
Over the past 10 years, research has shown that “urban adaptability is correlated* with traits like innovativeness, behavioural flexibility and exploration,” said the Max Planck Institute’s Dr Aplin. What the new research adds to that understanding is that animals that can easily transmit knowledge and new skills socially also have an advantage.
Parrots — which include cockatoos — are known for being among the most clever birds. They have a brain just the size of a walnut, but the density* of neurons* packed into their forebrains* gives many species cognitive abilities similar to great apes, said Dr Irene Pepperberg, an animal cognition researcher at Harvard.
Cockatoos are famously skilled at using and manipulating new tools, such as puzzle boxes in the lab or rubbish bin lids in the wild, she said.
“Everyone in Sydney has an opinion about cockatoos,” said the Australian Museum’s Dr Major. ”Whether you love to watch these big, flamboyant social birds, or think they’re a pest, you have to respect them. They’ve adapted so brilliantly to living with humans, to human domination of the environment.”
- ornithologist: person who studies or is an expert on birds
- ingenuity: being clever, original, inventive
- cognitive: of the mind, mental functions and processes
- ecologist: expert in the study of living organisms and their environment
- dominant: having power and influence over others
- hierarchies: systems ranking individuals according to status or authority
- flamboyant: confident, lively, animated
- thrived: growing or developing well
- opportunistic: taking every opportunity
- correlated: one thing affected or depending on another
- density: thickness, bulk
- neurons: basic units of the brain and nervous system
- By the end of 2019, birds were lifting bin lids in how many Sydney suburbs?
- What is the classic case in the UK, starting in the 1920s?
- How many cockatoo victories did Dr Clump record in summer 2019?
- Were the majority of birds in the study male or female?
- How large is a parrot’s brain?
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1. Cockatoo School
If you could get a group of willing cockatoos to attend ‘cockie school’ once a week, what things would you like to teach them that could help them survive in the wild?
From the article, which type of cockatoos show the best promise when it comes to learning new tricks?
Time: allow 15 minutes to complete this activity
Curriculum Links: English, Critical and Creative Thinking
“They’ve adapted so brilliantly to living with humans, to human domination of the environment.” In your opinion, how have cockatoos and other birds adapted their livelihoods to survive in a world of human domination?
Time: allow 10 minutes to complete this activity
Curriculum Links: English, Critical and Creative Thinking
An adjective is a describing word. They are often found describing a noun. To start with look at the words before the nouns.
Search for all the adjectives you can find in the article.
Did you find any repeat adjectives or are they all different?
Pick three of your favourite adjectives from the text and put them in your own sentences to show other ways to use them.
Have you used any in your writing?