Biology Professor David Craig and Kaeli Swift '09 discuss crows' ability to recognize people.
Kaeli Swift '09 feeds crows to study their reaction to friendly people.
Research Finds Crows Recognize and Remember Human Faces
Think twice before being mean to a crow — it could hold a grudge against you and tell its friends and family to do the same.
Willamette biology Professor David Craig recently co-authored a study, published in Animal Behaviour, which supports many people's anecdotal claims that birds recognize and remember people they consider to be a threat.
"Crows hold a grudge, and they are big gossips," Craig says. "They spread the information around. If you're bad to one crow, many more may hear about it."
Testing with Masks
Craig joined a team of researchers from the University of Washington to study crows' ability to distinguish among human faces. The researchers wore a caveman mask while trapping and banding crows on the Seattle campus, a traumatic experience for the birds.
From then on, anyone who donned the mask was harassed by the crows. It didn't matter who wore the mask — the crows responded to the face, not the body type or gender of the person.
When the researchers who had done the trapping wore a mask the crows had not seen before, one of Dick Cheney, the birds ignored them. The scientists also conducted experiments with more realistic-looking masks of people's faces and found the same results.
Not only did the crows recognize dangerous people, but they remembered them for a long time. Almost three years after someone initially trapped birds wearing the caveman mask, the crows still responded negatively to the mask.
And they shared their knowledge with other birds. Crows that were nowhere near the trapping incident also harassed the caveman, and young crows that hadn't even been born when the negative event occurred learned about the caveman from their parents.
"One of the most surprising parts of the study was the persistence of the crows' negative reactions over time, that for so long after a single event, they still remembered what they had learned about the caveman," Craig says. "It was also surprising that the crows passed on the information about the negative person to other crows and to their offspring."
Crows and Friendly People
Craig and several Willamette students are conducting a parallel study on the ways crows respond to positive people. Kaeli Swift '09 fed crows on campus while wearing different masks to see whether the birds were more likely to take food from a person they recognized versus someone who was unfamiliar.
The research with the masks is still inconclusive, but when Swift fed peanuts to crows alongside a woman who had been feeding them for years, the birds almost always took food from the woman they knew.
Ben Gutzler '10 and Jeffrey Kitts '10 will continue Swift's research project this year. The three students plan to co-author a paper with Craig on the project and submit it to Animal Behaviour in the future.
"That's the kind of experience that typically you would not get until you're in graduate school," Craig says. "My students are central to my research. Their open-ended questions, their intelligence and their creativity help us find new scientific problems that have not yet been tested."
Adapting to Humans
Next steps in the crow study could include trying to identify which specific facial features crows recognize, or seeing if other animals also distinguish among human faces.
Craig says we shouldn't be surprised that crows pay so much attention to us — we live in such close proximity to the birds that they are bound to observe our actions and react to them.
"Everybody has a crow story, and what we're learning is that crows probably have a story about people as well," he says. "In the long history of people and animals living together in and around cities, there appears to be evolutionary phenomena of crows adapting to us."