Cockatoos contain contradictions.
“They behave like gremlins,” said Antonio Osuna-Mascaró, a biologist at the University of Veterinary Medicine Vienna.
His colleague Alice Auersperg agreed.
“Imagine a toddler with pliers in their head,” she said, that is also able to fly.
But just like toddlers, cockatoos can be sweet and curious, always exploring the world around them.
Dr. Auersperg and other researchers showed the innateness of this curiosity in 2021, when they reported that wild Goffin’s cockatoos use tools. The researchers observed birds, temporarily housed in a field aviary, using their beaks to fashion three tools — a wedge, a knife and a spoon — to help them pry open tropical Wawai fruits, “like a set of cutlery,” Dr. Auersperg said. It was clear the cockatoos were crafting different tools for different purposes, known as a tool set, but a critical question remained: Did the birds see the tools that way?
In a study published Friday in Current Biology, Dr. Osuna-Mascaró, Dr. Auersperg and their colleagues showed that the cockatoos are only the third animal, besides humans and chimpanzees, known to select varying tools based on the tasks they expect to face.
The ability of chimpanzees to plan tool use ahead of time inspired the current cockatoo study, Dr. Osuna-Mascaró said. Chimps in northern Congo use a short, sturdy stick to punch a hole in termite nests and then a longer, thinner stick to fish the insects out and eat them. If the chimps know that they’ve already left a hole-puncher near a termite mound, they won’t bother bringing another one with them, showing that they think ahead of time about the tools they need for a task.
Dr. Osuna-Mascaró, who previously worked on chimps, adapted the termite fishing task for a group of captive cockatoos. Instead of bugs, the grand prize was a cashew, their favorite food. Getting the treat out of a puzzle box required two tools: a short, sharp tool that had to first cut a membrane blocking the bird’s access to the nut, and a long, flimsy pole that had to be stuck into the hole to fish out the cashew.
Once presented with the box and the tools, six of 10 cockatoos were able to innovate the correct solution. One, Figaro, figured it out in 31 seconds, and another, Fini, did it in 34 seconds.
The researchers then tested whether the cockatoos could pick the right tools to get a cashew from a simpler box, which had no membrane and thus required only the fishing pole. When given the simpler box, the birds picked up the pole significantly more than would be expected if they were choosing between the two tools at random, showing they understood that it was the right tool for the fishing task.
The critical experiment came next, when the box was moved farther from the tools, meaning the birds had to choose the right implements and then carry them over, either by climbing a ladder or flying a short distance. When deciding which tools to bring on their journey, the cockatoos planned ahead, like humans grabbing their phone, wallet and keys before heading out for the day. If facing a box with a membrane, the cockatoos figured out how to carry the tools together and would come prepared with both.
“They were able to recognize that they would need both tools in the near future,” Dr. Osuna-Mascaró said.
If the box didn’t have a membrane to be cut, the birds tended to bring just the fishing pole, much like the chimpanzees.
Crickette Sanz, a behavioral ecologist at Washington University in St. Louis whose prior work on chimpanzee tool use inspired the cockatoo study, said it “enriches our discussions of comparative cognition” when the similarities between cockatoos and chimpanzees were made so clear.
The researchers now hope to see if the cockatoos can manage this feat even when the box is not in direct view, and also further explore the evolutionary history of tool use in this species. For Dr. Osuna-Mascaró, this finding shows “how little we know about animals in general.”
Dr. Auersperg thinks the study proves a certain anti-avian turn of phrase needs revising.
“Bird brain,” she said, “should actually be a compliment.”
