How magpies outwitted researchers in Australia
During a recent study, a group of magpies removed their GPS trackers, astounding their observers. But were the birds actually trying to help each other?
When Dominique Potvin and her team set out to test a new technology for tracking birds, they didn’t think they were entering into an interspecies game of one-upmanship. Instead, Potvin, an animal ecologist at the University of the Sunshine Coast in Australia, was hoping to both track the animals’ movements and solve a persistent issue in the study of birds. Approximately 70% are too small to be tracked using a traditional battery-powered GPS tracker, since the weight of the devices can harm them. The new, harness-based trackers Potvin and her team had developed weighed only one gram, with a strap that could detach if the birds approached a specialized magnetic station. That would allow the researchers to collect the trackers without having to recapture the birds.
“We wanted to see if the new design would work as planned, and discover what kind of data we could gather,” Potvin wrote in a recent piece for The Conversation. “How far did magpies go? Did they have patterns or schedules throughout the day in terms of movement, and socialising? How did age, sex or dominance rank affect their activities?” Australian magpies also seemed to her a prime species for testing new tracking technology because of their larger size. The accepted size of a tracker in ornithology is about 3%-5% of an animal’s body weight. These new trackers weighed about 1%. “We were excited by the design,” she wrote.
But the magpies had other ideas. During the month that Potvin and her team spent fitting five magpies with trackers and watching their behavior, “we directly observed four actively removing the trackers,” they wrote in a study published last month in the journal Australian Field Ornithology. At first, the birds pecked at their own trackers—but then something more interesting happened. An adult female approached one of the juveniles fitted with a tracker and pecked at the device until it came apart and fell off. At the same time, elsewhere, another adult magpie also had its device destroyed by a companion. Soon, all the other trackers had been removed.
The team wasn’t too concerned when the magpies started pecking at the harnesses, “but the more time went on and the more they worked on the harness, the more worried we became,” Potvin said by email. “As soon as that first tracker came off, we just looked at each other in disbelief: we knew it was all over!”
She and her team were astonished. What, they wondered, could this unlikely outcome mean?
Potvin and her team saw the magpies’ tiny mutiny as something more than a stunt. Australian birds have a reputation for being collaborative. The continent is the world capital for cooperative breeding, where birds help raise chicks of the same species that aren’t their own—a behavior Australian magpies engage in. They’re also known for working together to defend their territories.
Since the magpies already have experience cooperating to solve problems, the authors argued, they might apply the same strategy to a new challenge. They interpreted the magpies’ removing each other’s trackers as altruistic behavior, or actions that only benefit another individual. The first magpie that destroyed another’s harness wasn’t wearing one itself, Potvin said over email, meaning that “the work was not going to be reciprocated.” She did note, however, that it’s possible the behavior might strengthen social relationships, creating long-term benefit. “These kinds of rewards are definitely plausible, but we have no way of knowing whether they played a part in this activity,” she wrote.
In looking for an explanation, Potvin and her team first thought of allopreening, a behavior where birds clean each other—sometimes removing parasites—to strengthen their bonds. But that is “a very straightforward behaviour, and does not involve any kind of determination, persistence or problem solving,” she wrote, “it’s not really ‘targeted’ with a specific goal in mind.”
Instead, they thought the most likely explanation was that the magpies were exhibiting “rescue behavior,” a very rare phenomenon in which one helper animal works to free a peer in distress, with no benefit to itself. Although the tracker was not dangerous, wearing it “may have felt a bit like being ‘tangled’” for the magpies, Potvin wrote, prompting other birds to respond.
The removal of the trackers represented a series of puzzles “requiring cooperation (the bird with the tracker had to stand pretty still for the other bird to work on them!), some altruism, and some cognitive problem solving,” she added. Such rescue behavior has been observed in Seychelles warblers, which sometimes get sticky seeds caught in their feathers, but until now researchers haven’t documented it in other birds. “It is possible that what we have observed is the first documented case of rescue behaviour in Australian Magpies,” the team concluded in its study.
Gisela Kaplan, a professor of animal behavior and zoologist at the University of New England in Australia who has studied Australian magpies for decades, agrees that pilot studies like Potvin’s are valuable for testing new technology on a small scale. But she emphasizes that the group of five magpies was likely a family, making the observations tantamount to one single anecdote. “I’ve seen lots of individual behaviors in magpies that I couldn’t explain,” Kaplan says—for example, she has written for The Conversation about a magpie in her yard who appeared to be gardening with her, and another instance in which one flew into her home and pecked at her keyboard after watching her type—“but I wouldn’t have written a paper about it.”
Lisa Horn, a comparative behavior researcher in Vienna, Austria, who studies altruistic behavior, agrees—especially since the team didn’t set out to test that kind of behavior. “Coming from a tradition of cognitive biology, we’re very careful with our experimental design, to try to rule out any other explanations and carefully control the conditions,” she says. But that kind of design is impossible when the outcome is an accident.
Kaplan suggests there are other possible explanations for the magpies’ digital striptease that could be just as interesting, including “play behavior, competitive behavior, all sorts of things.” Kaplan’s research has shown that juvenile magpies play quite a lot, including among themselves and with objects. “The object play that I’ve observed is always competitive,” she says, adding that many of those play interactions include stealing a desired item.
Another possibility, Horn suggests, is simple distress. “A lot of songbirds, and also Australian magpies, have very close social bonds with their partner,” she says. “If something happens to my mate, and it freaks my mate out, that also freaks me out.” That leads to what Horn calls “emotional contagion,” and the desire on all sides to resolve the distressing situation. This is a much simpler mechanism that is found in a wider array of animals than generosity, empathy, or altruism, she says. The danger in such circumstances is anthropomorphism, ascribing human experiences to animals because that’s how we might behave or feel. “Especially in cognitive biology and behavioral biology, we are very careful with using these terms,” she says.
But while Potvin agrees that being thoughtful about anthropomorphism is important, she feels it can sometimes be “helpful, or even somewhat accurate” to consider the parallels between human and animal behavior. “The risk comes when we think we know what the birds are actually thinking,” she said over email. For example, they don’t know how the birds viewed the trackers, nor their problem solving strategy for removing them. “But we do know what they did, and that in and of itself is pretty impressive.”
Both Horn and Kaplan agree that the idea that the magpies may exhibit rescue behavior is plausible. After all, the birds are remarkably cooperative in other ways. Plus, similarly empathetic “consoling” behavior has been observed a few times in ravens. And in Horn’s own research, she found that certain crows and magpies (though not the kind in Potvin’s study) were particularly likely to help others. Since both of the species in Horn’s research were also cooperative breeders, she hypothesizes that having “such a family system—parents but also maybe aunts, uncles, someone else helping—seems to have led to a lot of this prosocial behavior in other areas.”
But, Kaplan says, jumping right to rescue is a big deal because it implies empathy, or even “theory of mind,” the ability to imagine an experience different than one’s own—which all but the most intelligent animals lack. And even if it turns out that magpies do have theory of mind, that’s a separate thing from saying “I care,” Horn adds.
Still, Potvin feels it’s not such an enormous leap, given that magpies’ cognitive abilities and complex social relationships are well established. Since the publication of her study, many readers have reached out to her to describe instances they’ve seen of similar behavior that appears altruistic or “rescue-like.” Could that suggest the behavior may be more common than previously thought? “I think that many people who watch and study birds have seen similar behaviours,” she wrote by email, “and thus the evidence is there for them.”
Kaplan hopes that Potvin and her team (or someone else in the avian cognition community) will use these observations as a jumping off point, carefully designing an experiment to test their rescue behavior hypothesis —perhaps a study to see if Australian magpies would work together to get food or would help a peer weighed down with some burden or restriction similar to the trackers. The study makes a great starting point, she says: Accidental observations are “often how further experiments start.” She points to Alexander Fleming’s discovery of Penicillin on a moldy dish. “The important point was that he didn’t expect that result but was in the right place at the right time and had the training to pursue this in a scientific manner,” she says. Someone else might have spotted the mold and thrown the whole thing away. “But he didn’t. He thought it was a significant event.”