We've been feeding a small family of four crows (mated pair and their two year old kids) for several years. Last week two days in a row they left these gifts, pull tabs threaded onto pine twigs. This isn't only generous, it's creative, it's art.
鈥 Stuart Dahlquist (@StuartDahlquist)
My mind is blown.
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Stuart Dahlquist had been feeding a family of American Crows in his backyard for more than four years before the crows gave him something back. At least, in his view.
One recent morning in March, Dahlquist stepped outside his home northeast of Seattle and noticed a short pine sprig with a soda tab threaded through the end. It was positioned right by his backdoor, exactly where he leaves an offering of dried cat food each day. The next day he found a second sprig identical to the first in the same spot. He and his wife walked the neighborhood, but couldn鈥檛 find another explanation for the strange objects. The crows, they reasoned, must have looped the tags onto the pine stems and left them behind for their human benefactors to find.
Dahlquist, a musician and handyman who runs a pet door installation business, of the twigs on Twitter. 鈥淭his isn鈥檛 only generous, it鈥檚 creative, it鈥檚 art,鈥 he wrote. It went viral, with more than 9,000 retweets and 33,000 likes.
But is it truly possible that crows crafted these objects and purposefully left them for Dahlquist to find?
鈥淚t鈥檚 definitely not a behavior that I鈥檝e ever seen before,鈥 says Kaeli Swift, an animal behaviorist who studies corvids at the University of Washington. 鈥淏ut it wouldn鈥檛 necessarily surprise me if a crow did it.鈥
Crows, as members of the corvid family, are highly intelligent creatures that make tools, recognize individual humans, and learn from one another. Wild crows are not known to create or display art. But they do occasionally leave behind objects like keys, lost earrings, bones, or rocks, for the people who feed them, a behavior that John Marzluff, conservation ecologist and Swift鈥檚 colleague at the University of Washington, calls 鈥済ifting.鈥
Marzluff first learned about gifting in the early 2000s when collecting stories for a new book about crow intelligence. A man who had fed crows in his backyard for years told Marzluff that, one day, he found a candy heart perched on his bird feeder. Although skeptical at first, Marzluff couldn鈥檛 find another reasonable explanation for the heart鈥檚 appearance other than the crow had left it there.
Not everyone who feeds crows receives strange objects, but there is enough anecdotal evidence that Marzluff has no doubt it happens. The behavior isn鈥檛 well studied, but limited evidence suggests corvids act differently around people they are familiar with. For example, from the Konrad Lorenz Institute in Austria showed ravens and crows were more motivated to exchange objects with human experimenters they knew, rather than humans they didn鈥檛.
What scientists can鈥檛 know, however, is why the birds leave behind these objects. 鈥淚n animal behavior that is always the sticky point鈥 intention 鈥 because we cannot ask them,鈥 says Jennifer Campbell-Smith, a behavioral ecologist who earned her PhD studying crows at Binghamton University.
Humans are quick to assume that the crows leave behind objects as acts of gratitude. After all, people often find 鈥済ifts鈥 where they feed the corvids, implying some kind of reciprocity. But when we assume gratitude, we project human emotions onto animals, says Swift.
Rather, gifting behavior could easily start out as an accident, she says. Curious crows will often fly off with an object, then lose interest and leave it behind. If the crow happened to leave an object where humans put out food, those humans might get excited and lay out even more food. The crow would learn that leaving behind random objects means a bigger meal and could teach other crows in the family to do the same. 鈥淚f you鈥檝e ever trained a dog, you know food is an amazing motivator to reinforce behavior,鈥 Swift says.
Creating a 鈥済ift鈥 by purposefully threading metal soda tabs onto twigs would take this behavior a step beyond what these scientists have seen before. But Marzluff and Campbell-Smith also would not rule out that Dahlquist鈥檚 crows had made the soda-tab twigs. 鈥淚 am very skeptical of random internet sources, but knowing these birds and how intelligent they are, I wouldn鈥檛 be shocked,鈥 says Campbell-Smith.
We may not know why crows do what they do, but that doesn鈥檛 make these creatures any less fascinating, says Swift. 鈥淚t鈥檚 still an amazing example of the way crows are really watching us and are mindful of us鈥攁nd, in their own way, [are] data mining for the best way to manipulate us," she says.
For his part, Dahlquist plans to continue feeding the crows and is considering getting a tattoo of the pine sprigs. He wishes he could tell the crows about his viral post. But the crows are still crows, and you can鈥檛 eat a tweet.