The wild crows learn to take butts and other small waste to a machine. In exchange for each donation, the machine issues a peanut. The crow service must reduce the costs of picking up butts.
The initiator of the plan is economic behavioral scientist Christian Günther-Hanssen. With his company corvid cleaning (Corvidae is the biological family name for crows) he developed a training program in recent months. He chose crows because he believes they are the most intelligent birds. ‘They are easy to train and there is a good chance that they will learn from each other. At the same time, the chance that they accidentally eat waste is small.’
Until now, Günther-Hanssen had the most success with hooded crows. He was able to train four of them to clear cigarette butts for extended periods of time. He also wants to try it with the jackdaws soon, because they move in larger groups.
As smart as chimpanzees
Research into cognition in birds shows that, for example, magpies, rooks and crows are just as smart as chimpanzees. For example, Japanese crows have learned to drop nuts on the road so that passing cars crack them. When the traffic light is red, they pick up the nuts.
They can also learn to pick up butts in exchange for a reward. This is badly needed, because according to the action group Keep Sweden Clean (Håll Sverige Rent), a billion butts are thrown on the ground in Sweden every year. It costs municipalities a lot of money every year to clean up streets, squares and parks.
Before crows are definitively included in the urban cleansing, there are still a number of hurdles to overcome. For example, Günther-Hanssen is still looking for financing for the pilot. Södertälje (100 thousand inhabitants) is looking for suitable places to put the butt-for-peanut machines.
Elsewhere, crows are already being used to pick up butts. For example, the French historical theme park Puy du Fou announced in 2018 that it would use six crows. ‘But those were tame crows, which is a big difference,’ says Günther-Hanssen. ‘Working with wild birds is more difficult. If they get bored or can get better food elsewhere, they’re gone.’
According to Günther-Hanssen, this will be the first project in which wild birds will actually clean up urban waste. If it is a success, he also wants to use crows elsewhere to clean. “There’s nothing stopping us from trying it in other places as well. Think of the beaches where so much waste washes up.’