In the quest to convince smokers to stop tossing cigarette butts on the street, cities have experimented with “ballot bins” that let people drop in butts to vote for a favorite soccer player, trash cans that light up and play music, pricey marketing campaigns, fines, and even jail time. Still, by some estimates, 4.5 trillion butts are littered each year, and the chemicals and plastic waste inside often end up polluting water.
A Dutch startup has an unlikely suggestion: If it’s hard to train humans to stop trashing cigarette butts, maybe we can train crows to collect the litter and keep streets clean instead.
When designers at Amsterdam-based design agency Crowded Cities began considering ways to clean up cigarette filters, they initially considered a Roomba-like outdoor vacuum cleaner, but realized that manufacturing the machines would have environmental impacts of its own, and the vacuums would struggle to collect litter from hard-to-reach places.
“Then we started looking at the environment and realized we could maybe use pigeons,” designers Ruben van der Vleuten and Bob Spikman write in an email to Fast Company. “Through doing research on training birds we found out crows are very smart, and we found out about a project by Joshua Klein about training crows. This is when we noticed: Would this maybe be possible?”
Klein, an American hacker and writer, built a DIY crow vending machine–the subject of a 2008 TED talk–after studying the intelligence of the birds. Crows can make complex tools to get food or carry objects, solve puzzles, and hold grudges; Klein found that they could also learn to use his “vending machine,” putting spare change in the machine to make it dispense peanuts.
He trained crows using the classic principles of behaviorist B.F. Skinner, who trained rats to push buttons, his family cats to play piano, and pigeons to play a bird version of ping-pong in the 1950s. First, Klein set up the machine to dispense both coins and peanuts when the birds flew away, so they would get used to the sound; then he set it to dispense both when the birds arrived, so they would expect to wait. In a third stage, coins were dispensed when the birds arrived–but the crows had to experiment to discover that when the coins fell down a funnel, they’d get a peanut (they figured it out). In the final stage, coins weren’t dispensed, but just left lying on the machine.
Van der Vleuten and Spikman plan to take a similar approach with their machine, called the Crowbar. If a bird drops a cigarette butt in the machine’s funnel, a camera will verify that it’s a cigarette, and then the machine will automatically dispense a small piece of food. They expect the birds to learn quickly. “With existing software and hardware we can make it possible to setup an autonomous training schedule,” they say. In theory, because crows appear to be able to teach each other skills–for example, crows in Japan taught each other how to use passing cars to crack open nuts–the birds should be able to teach each other how to collect cigarette butts for rewards.
First, however, they plan to work with experts to better understand whether there are any risks to the crows. If birds eat cigarette filters–which contain arsenic and lead, among other things–the chemicals can sometimes poison and kill them. (Some birds also use cigarette filters to line their nests, so to a certain extent, they’re already helping to clean up streets.) If it turns out that enlisting crows as maintenance workers harms their health, the designers will look for another solution.
Klein, who plans to soon launch an open-source version of the crow vending machine so that others can experiment with it, says that he tries to work with wild animals in a way that “leaves them better off for the experience,” and hopes that others inspired by his work, including Crowded Cities, do the same.
“It may turn out that crows can handle cigarette butts with no harm at all, in which case both crows and humans could benefit,” he says. “That’s the kind of solution I’m looking for: Crows aren’t going away anytime soon, and it’d be nice to find a way for us to work cooperatively.”
One crow expert argues that humans should do the job instead. “First, I think crows could learn the task and that they might do it if the rewards to them are high,” John Marzluff, a professor of forest sciences at the University of Washington writes in an email. “But I think it is unethical to ask a wild animal to do our dirty work. Crows have other things to do, being highly social animals and intelligent, and it doesn’t seem right to me to enslave them to work for us. Why not just pay people a good wage to do the work?”
For their part, the Dutch designers hope that the project also makes more people aware of the problem of litter so fewer cigarettes are tossed on the street in the first place. “It’s very important to us to raise this question,” they say. “Why is it still socially acceptable to toss these toxic, plastic filters into nature? Since people don’t encounter a direct effect of the filters on the ground, like chewing gum can have a direct effect, it seems to be overlooked. We need to start realizing how big this cigarette [litter] problem actually is.”