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Photo: Australian Museum.
The Australian Magpie is a clever songbird that inhabits nearly 90 percent of mainland Australia.

Today’s article by Anthony Ham at the New York Times is reminding me of the children’s book Mrs. Frisby and the Rats of NIMH, in which a determined mouse helps lab rats escape from scientists using them for experiments.

He writes, “The Australian magpie is one of the cleverest birds on earth. It has a beautiful song of extraordinary complexity. It can recognize and remember up to 30 different human faces.

“But Australians know magpies best for their penchant for mischief. … Magpies’ latest mischief has been to outwit the scientists who would study them. Scientists showed in a study published [in] the journal Australian Field Ornithology just how clever magpies really are and, in the process, revealed a highly unusual example in nature of birds helping one another without any apparent tangible benefit to themselves.

“In 2019, Dominique Potvin, an animal ecologist at University of the Sunshine Coast in Australia, set out to study magpie social behavior. She and her team spent around six months perfecting a harness that would carry miniature tracking devices in a way that was unintrusive for magpies. They believed it would be nearly impossible for magpies to remove the harnesses from their own bodies.

“Dr. Potvin and her team attached the tracking devices and the birds flew off, showing no signs of obvious distress. Then everything began to unravel.

“ ‘The first tracker was off half an hour after we put it on,’ she said. ‘We were literally packing up our gear and watching it happen.’

“In a remarkable act of cooperation, the magpie wearing the tracker remained still while the other magpie worked at the harness with its beak. Within 20 minutes, the helping magpie had found the only weak point — a single clasp, barely a millimeter long — and snipped it with its beak. …

The scientists took six months to reach this point. Within three days, the magpies had removed all five devices.

“ ‘At first it was heartbreaking,’ Dr. Potvin said, ‘but we didn’t realize how special it was. We went back to the literature and asked ourselves, “What did we miss?” But there was nothing because this was actually new behavior.’

“The only similar example of what Dr. Potvin described as ‘altruistic rescue behavior’ — where birds help other birds without receiving tangible benefits in return — was when Seychelles warblers helped other members of their social group escape from sticky seed clusters in which they had become entangled.

“The magpies’ behavior was, Dr. Potvin said, ‘a special combination of helping but also problem solving, of being really social and having this cognitive ability to solve puzzles.’ …

“The Australian magpie is a large black-and-white perching songbird, or passerine, that inhabits nearly 90 percent of mainland Australia. … Remarkably, magpies can recognize the faces of as many as 30 people, which is the average number who live within a magpie’s territory, which is the average number who live within a magpie’s territory. ‘Very rarely do magpies attack more than one or two people,’ said Darryl Jones, a magpie expert at Griffith University. ‘It’s the same individual people that they attack each time.’

“And magpies have long memories: One of Dr. Jones’s research assistants was attacked upon his return after 15 years away from one bird’s territory. …

“If more than 30 people pass through a bird’s territory, ‘they actually start stereotyping people,’ [Sean Dooley, the public affairs manager of Birdlife Australia] said. ‘People who resemble 10-year-old boys are much more likely to be swooped, because those are the kids who are more likely to be throwing sticks and stones, shouting and chasing and running at magpies.’

“Dr. Jones calls the magpies’ ‘gorgeous, glorious caroling song’ another example of their intelligence.

“With more than 300 separate elements, he said, ‘it’s unbelievably complex. In order to remember and repeat a song of that complexity every single morning without error, you have to have a big brain.’

“Dr. Potvin and her team have shelved their original study. But they can’t help but ponder a bigger question: ‘What else are magpies capable of?’ ”

More at the Times, here.

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murmuration-1Photo: Daniel Biber, via the Independent
A murmuration of starlings was targeted by a bird of prey and took the form of a giant bird. But contemporary scientists insist “thinking” isn’t involved. 

The natural world never ceases to amaze. Consider the flight of large groups of starlings. You have probably seen some of the YouTube videos. Mark MacNamara wrote about the phenomenon at Nautilus in March.

“Eugene Schieffelin was the eccentric ornithologist who in 1890 shipped 60 starlings from London to New York City and set them free in Central Park. The next year he released 40 more, and today there are maybe 200 million starlings in the United States and Southern Canada. [Starlings] are shrewd flyers, clever mimics, and often unwelcome … displacing woodpeckers and flycatchers, and destroying entire crops of berries and cherries. Not to mention the havoc they cause at many airports.

“Ah, but when they come round in their murmurations on fall afternoons, or in early winter, what magicianry is that, gathering up out of nowhere, arriving in strands or massive clusters, over inlets or forests. You’ll see them fill up neighboring trees and fall into an oily, high-pitched chatter. [The] most subtle spooking will do it, a dog’s bark, the slam of a car door down the street, or nothing at all, and off they go at 50 miles per hour, wheeling around the countryside, sheets and sheets of them, thickening and thinning, blackening and scattering, merging and splitting. …

“The performance is self-organized, cohesive, and perfectly synchronized; and distinguished by elaborate patterns of spirals, spheres, planes, and waves. What causes starlings to perform these displays? …

“Theories have evolved over the last century. In 1931, Edmund Selous, a renowned ornithologist and bird activist [sumised] that birds in a flock must all be ‘thinking’ as one; how else to explain the synchronization except by telepathy. …

“Later theories suggested that murmurations are ways to find food and keep warm. Those theories linger, but in the past 50 years the predominant explanation is predation, particularly the role of raptors, such as hawks and falcons, in triggering escape behaviors that involve particular patterns of grouping. …

“In the mid 1960s, researchers found that murmurating birds, particularly starlings, interact—not always, but often — with six or seven of their closest neighbors, who interact with six or seven of their closest neighbors. In recent years, studies posit that a network with seven neighbors optimizes the trade-off between ‘group cohesion and individual effort.’

One theory among researchers, in the context of predation, is that starlings are ‘managing uncertainty while maintaining consensus.’ …

“In a murmuration, the distance between fellow fliers is based on a set of rules also seen in certain kinds of fish and insects. These rules require birds to draw closer to birds farther away; at the same time, not to get too close to the nearest neighbor; and finally to join in directional flow. Add to these rules the aerodynamic factors in starlings — and the blistering speed at which the birds turn, climb, and dive — and you have a sense of the intricacy of flock synchronization. …

“In 2019, evolutionary biologist Rolf F. Storms at the Groningen Institute for Evolutionary Life Sciences in the Netherlands, led a study on starlings that delved into the rules of murmurations. … The study [found] different patterns of escape by the starlings.

“For example, when a falcon attacked a flock from above — not from the sides or below, and at high speed — the starlings frequently [scatter] in all directions in the sky. … When a falcon attacks starlings at medium speed, allowing it to be detected, warnings spread through the flock, and the birds respond in a ‘wave.’ They turn right and left, zig and zag, creating ‘darkened bands’ that ripple through the flock, confusing the falcon. …

“Grainger Hunt, Senior Scientist Emeritus with the Peregrine Fund’s California Condor and Aplomado Falcon restoration project, underscores the fact that murmurations are emergent. …

” ‘The peregrine does not purpose the shapes and movements of the flock. Nor does any starling. The spectacle of wondrous shapes and movements is an unintended effect. The peregrine is trying to catch a starling, and each starling is trying not to get caught.’ ” More.

Would you agree that humans need to learn from the starlings how to maintain consensus while managing uncertainty? What a concept!

Video: Dylan Winter
A murmuration of starlings.

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