Crows have long been associated with creepiness. After all, a group of them is called a "murder." But maybe the birds have gotten a bad rap — maybe their most unsettling quality is really just how smart they are.
To get some insight into crows and perhaps set the record straight, Short Wave spoke with Kaeli Swift, a lecturer at the University of Washington who wrote her doctoral thesis on crow behavior. She cites three examples of crow smarts.
1. Crows can memorize human faces
Wildlife biologists figured this out by conducting a simple experiment using rubber masks. A "caveman" mask, for example, designated a "dangerous" face while a mask of former Vice President Dick Cheney was "neutral." Researchers in the dangerous mask trapped and banded individual American crows and then released them. While they were careful not to harm the birds during trapping, "it's still a scary experience for the bird," Swift says.
To see whether the crows remembered the dangerous face, researchers returned to the area and walked around wearing the different masks. And when the birds saw the dangerous face, Swift says, "they would alarm-call, they would dive-bomb that person." The neutral face was mostly ignored.
The gender or body type of whoever was wearing the dangerous mask didn't much matter — the crows seemed to key in on the face. Researchers even flipped the mask upside down to see if the crows could still recognize it. "For a brief moment, the crows seemed a little confused, and then they would just tilt their head upside down and then they'd start an alarm-calling," Swift says.
Even crows that hadn't been tagged or banded scolded and dive-bombed the wearer of the dangerous mask. Swift says this suggests the crows "were actually learning from their peers that this particular person is dangerous."
And if you need another reason to be nice to crows, they can also remember faces for years.
2. Crows have "funerals" for their dead
Humans aren't the only animals to note their departed. American crows mark the passing of their dead in two ways: with alarm calls or a series of loud scolds, and with mobbing. Mobbing is when multiple crows hear an alarm call, gather around the dead crow and also begin to scold. "This usually lasts around 15 to 20 minutes," Swift says.
Swift and research partner John Marzluff, who led the facial-recognition study, did an experiment to understand why American crows do this. It turns out that the "funerals" have less to do with dirges and eulogies and more to do with identifying the cause of death. And with spreading the word about potential dangers.
The researchers fed crows over the course of several days to attract the crows to the area and figure out how long it took them to come down for a snack.
Then a person wearing a mask carried a dead crow into the area. The crows scolded and dive-bombed that person. Later, if someone wearing the same mask returned to the area — even if they weren't bearing a dead crow — the birds scolded and dive-bombed them again. "Basically," Swift says, "if they saw a person holding a dead crow would they learn that person's face and go, you know, guilty by association."
The crows were also slower to return to the feeding grounds once the area became associated with danger. Swift says this "suggests that crows did indeed learn from that experience, that although those Cheetos might be really tempting, because there was a dead crow here earlier, I should probably be extra careful before I come down and get my snack." Same, crows. Same.
3. Crows create and use tools.
When we think of animals using tools, we often think of primates. But crows surprise yet again. As Swift puts it, New Caledonian crows are basically "flying primates" because they create hooked tools — essentially twigs shaped into hooks to fish out bugs burrowed in wood.
"There's a lot of animals that use tools, but modifying a material for a specific purpose, that's much more complicated," she says. Swift adds that while some primates have made tools in captivity, she thinks these crows might be "the only other animal besides early humans that habitually make hooks in the wild."
So next time you come across a crow, maybe treat it with a little more respect. After all, the crow won't forget.
This episode was produced by Rebecca Ramirez and Ariela Zebede. It was edited by Viet Le and Gisele Grayson. Maddie Sofia checked the facts.