Putting humans to shame: intelligent crows pick up after smokers

A municipality in Sweden is trialling the use of crows to pick up trash - cigarette butts, to be exact.

The municipality of Sodertalje, with around a hundred thousand residents, is planning to reward the clever birds with food each time they deposit a cigarette butt into a special waste receptacle.

Built by a start up company called Corvid Cleaning, the machine dispenses pellets of food for the crows as positive reinforcement. “They are wild birds taking part on a voluntary basis,” says Christian Gunther-Hanssen, the founder of Corvid Cleaning.

Gunther-Hanssen tells Swedish news agency TT that Corvid Cleaning chose crows for litter pick-up because they are the most intelligent birds.

“They are easier to teach and there is also a higher chance of them learning from each other. At the same time, there’s a lower risk of them mistakenly eating any rubbish,” he says.

The Keep Sweden Tidy Foundation, an environmental non-profit, estimates that over a billion cigarette butts are dispensed on Sweden’s streets per year, and they represent 62 percent of all litter.

Corvid Cleaning’s worker crows are ready to be put to large-scale use where a potential pilot project will be carried out in Sodertalje municipality.

Thomas Thernstrom, waste strategist at Sodertalje municipality, tells TT that “It depends on whether we can find a place in Sodertalje which will work with the food dispenser, and then if there are opportunities for financing.”

This is not the first time that smart crows have been put to use for the benefit of dirty humanity. In 2018, for example, crows helped keep a French theme park litter-free.

Gunther-Hanssen suggests that having crows do the heavy lifting in fighting cigarette butt litter may save the municipality up to 75 percent on costs.

“The estimation for the cost of picking up cigarette butts today is around 80 ore (12 cents) or more per cigarette butt, some say 2 kronor (30 cents). If the crows pick up cigarette butts, this would maybe be 20 ore (3 cents) per cigarette butt,” Gunther-Hanssen calculates.

“The saving for the municipality depends on how many cigarette butts the crows pick up.”

The pilot project, if successful, will pave the way to a wider application of the crow trash pick up scheme. Thernstrom tells TT that if it’s possible, they would like to get going this spring.

“It would be interesting to see if this could work in other environments as well,” the waste strategist says. 

“Also from the perspective that we can teach crows to pick up cigarette butts but we can’t teach people not to throw them on the ground. That’s an interesting thought.”