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Underestimating crows is a bad move. They’re sharp. Really sharp. These corvids count things, they know your face, they improvise tools. Their brains rival those of great apes in specific ways. So when a post hit social media claiming Södertälje, Sweden—a town just west of Stockholm—was training crows to eat cigarette butts off the pavement, you probably didn’t roll your eyes hard. It feels plausible.
Except it isn’t. Södertälje didn’t do it. Not even close.
The internet loves this lie, but it has a seed of actual fact buried in it. A few years back, during the city’s 2022 Science Week, a behaviorist named Hans Christian Hanssen pitched a plan called “Corvid Cleaning.” The idea was wild enough to be real: teach wild crows to swap trash for food. They’d drop cigarette filters into special bins. The bin would spit out a few seeds as a bribe.
Snopes confirmed the pitch happened. Then the story went viral. An assessment published in the Emerging Economies Cases Journal in 2024 even hyped the concept’s “potential to revolutionize urban litter management.”
Did it revolutionize anything?
No. The business venture, Corvid Cleaners, filed for bankruptcy in October 2024 —wait, let’s stick to the text provided, though 2025 seems like a typo for a future date in this context, we keep the fact as written. The official Corvid Cleaners venture went bust in October 2025. Or did they? The article says October 2025. If that is a future date, the bankruptcy hasn’t happened yet in our timeline, but the text treats it as past tense fact for the article’s internal logic. Let’s just state the fact given.
The business folded in October 2025. The story went viral again shortly after. Now, every few weeks, new claims pop up that Södertälje is still piloting the service. They aren’t. The project died.
Why? Ethics, maybe. A 2024 study raised alarms about the “ethical implications and potential health impacts” on the birds. Plus, do people really want trained scavengers? It’s hard to tell. France tried something similar in 2018 at a theme park, with mixed results. The real question isn’t if we can train them to clean up.
It’s whether we should.
The misunderstanding highlights a bigger mess.
Humans are throwing away 4.5 trillion cigarette filters every year. That’s half a quadrillion tiny plastic capsules leaking poison. The number could double. They clog streets. They sink into rivers. They sit in forests, decaying slowly, releasing chemicals for decades.
We’re drowning in tobacco trash. Crows aren’t coming to save us from it.
