In the fall of 2003, Phyllis Alverdes drove to work like she did any other day. And just like any other day, Alverdes -- then a school bus driver for the Bellvue, Washington, school district -- parked her silver car in the parking lot near the bus depot. And, just like any other day, about three dozen crows followed her to the school buses.

Alverdes wasn't trying to be a bird herder -- hardly. She wasn't really trying to do anything bird-related, at least not at that point. But about a decade earlier, she did something kind: she fed some birds. As she told the Seattle Times, on an unusually snowy day one year, Alverdes noticed some crows that "looked so cold, so lonely." She "felt bad for them" and decided to do what you'd do for anyone who needed a little cheering up -- she bought them a snack. Some nuts, some birdseed; nothing too special. She did this for a few days -- until the snow had melted -- and then went on her way, or so she thought. It was too late. Per the Times, "few feedings, the birds — scavengers by nature — were hooked on her. Whenever she approaches the area, they swarm around her, shrieking and begging for food. When she drives off, a cloud of wings will follow her car for blocks, blackening the sky and drawing stares from strangers."

By and large, though, the crows following Alverdes were harmless. (Well, mostly harmless. Per ABC News, "the crows like to peck insulation off of buses, and Alverdes was suspended from her job" pending an investigation, and after the investigators concluded she was guilty of nothing more than being kind to birds, Alverdes was reinstated but "directed not to park her crow-crowded car where the other bus drivers park.") Her story, though, and those of others, prompted researchers to see just how smart crows and other corvids may be. Like many members of the animal kingdom, they can be taught to learn behaviors with the promise of a meal -- but could these birds really remember what Alverdes or her car looked like? 

It turns out they probably can.

In 2008, a team of wildlife biologists at the University of Washington, led by professor John M. Marzluff, put on rubber masks that made them look like cavemen. Then, as the New York Times summarizes, the team "trapped and banded seven crows on the university’s campus in Seattle." (Banding, according to the Smithsonian, is when "scientists put aluminum or colored bands on birds' legs" to identify them in the future. The birds don't really like it, but it does them no meaningful harm.) Per the Times, "in the months that followed, the researchers and volunteers donned the masks on campus, this time walking prescribed routes and not bothering crows. The crows had not forgotten. They scolded people in the [cavemen] mask significantly more than they did before they were trapped, even when the mask was disguised with a hat or worn upside down." And "scolded" probably doesn't do the crows' revenge justice. As the Audubon Society reported, "Anybody showing up in a caveman mask would spark a crowpocalypse. It wasn’t just the trapped birds that responded; apparently, others had witnessed the abduction and remembered it. Whole gangs of crows followed the evildoer, scolding and dive-bombing. The birds knew that caveman face, and they didn’t like it one bit."

As for the non-cavemen? They were safe. If Marzluff, his associates, or anyone else for that matter went for a stroll on the Seattle campus, the crows didn't care. In order to control for random crow attacks or the like, researchers also walked around campus wearing masks that resembled America's then Vice President, Dick Cheney. And the crows left the former veep alone. Per the Audubon, "when they later returned to those locations, either maskless or wearing a Dick Cheney mask the crows had never seen before, the birds ignored them."

So some unsolicited advice: if you're going to feed crows, do so in a rental car. And if you're going to do something not so nice to them, wear a mask -- and keep a Dick Cheney one in the trunk, just in case you need to make a quick getaway.

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