In Utrecht, fish and other aquatic creatures now have an underwater “doorbell” to call for help as they make their way to their spawning grounds.
Each spring, thousands of fish embark on an upstream journey along the Vecht River but often get stuck at the gates of the historic Weerdsluis lock. Built around 1300 to regulate canal water levels and designated a national monument in 1992, the lock doesn’t open frequently enough for the eager swimmers.
To ease the traffic jam, the city council and water authorities installed a camera that livestreams the waiting fish. Locals who spot a stranded fish can ring the virtual bell, sending screenshots to the lock keeper, who then opens the gates and lets the fish pass.
The goal isn’t to grant passage to every single fish, but to ensure the lock opens at least once a day. And for anyone tuning in, watching determined fish on their migration makes for an unexpectedly engaging show.
After all, they’re traveling farther than most of us these days—and this isn’t the first remarkable fish tale. In 2014, one adventurous fish even learned to drive its own tank around a room.
