Help fish navigate Dutch canals by ringing a digital doorbell

Why are over 2,000 people watching a live feed of murky water in a canal somewhere in the Netherlands? To ring the visdeurbel, of course.

As it has since 2021, the Dutch city of Utrecht’s annual Visdeurbel — or in English, “fish doorbell” — project went live on March 3, allowing folks around the world the ability to assist thousands of fish in navigating the municipality’s Oudegracht canal as they migrate to mate and lay eggs. The instructions for viewers are simple: if you see a fish on the camera, you help them out by pressing the website’s digital doorbell and alerting an on-location lock keeper, who then opens a sluice gate and allows the fish to pass. It’s like a video game, but in this version, you help real fish make it upstream.

“By ringing the Fish Doorbell, we not only help the fish, but also nature and water quality in and around Utrecht,” said local water authority member Gijs Stigter leading up to this year’s event. “Fish let us know how the water is doing. If certain species thrive, such as pike, that is a sign of clean and healthy water. The water authority uses this information to further improve water quality.”

Visdeurbel attracted almost 3 million unique visitors last year, according to Utrecht alderman Linda Voortman.

The project provides three tips for aspiring doorbell ringers. First, tune in during the morning and evening hours — Utrecht is located in the Central European time zone — as that’s when the fish are most active. Second, migration picks up in April, so while it’s possible to see fish right now, it’ll be more likely starting next month. And finally, special species like eel and zander only show up when the sun goes down. Past livestreams have apparently also featured appearances from crabs, lobsters, frogs, and geese.

If you happen to check out the Visdeurbel website and don’t see a doorbell to ring, never fear — the digital button is programmed to disappear for latecomers when the stream gets crowded. Keep checking back for your opportunity to help our underwater friends get their freak on.