Local ecologists came up with an ingenious solution: the world’s first fish doorbell or visdeurbel in Dutch (try saying it out loud). If webcam watchers spot fish waiting to pass, they simply press a virtual doorbell and the lock keeper — who can’t see down into the water, which is 2.1 metres (7ft) deep, from dry land — is sent a notification. When enough fish have gathered, the operator opens the 200-year-old sluice gate by hand to let them through. It enables professionals and the public to work together around the clock, ensuring fish don’t have to wait too long. Like a marine midwife or damp doula, you can help them reach their spawning sites unscathed. It means they’re less likely to fall victim to predators such as herons, cormorants and grebes (boo! baddies!).
The project is a collaboration between water authorities and the municipality of Utrecht as fish are a vital part of the ecosystem, eating insects and maintaining the cleanliness of canals. It also provides data about the plentiful wildlife beneath the serene surface of the city’s waterways. No wonder visitors are logging on to lend a hand, waving through 2,000 fish a week. Politely holding a door open for our scaly pals — who lack the opposable fins to do it themselves — is a feelgood act of kindness. The green-tinged live feed is like a calming version of that giant puddle in Newcastle or an eco equivalent of Big Jet TV. It’s wholesome, interactive and addictive, akin to a soggy Springwatch or a low-budget Blue Planet. “In spring 2021, the doorbell was rung more than 100,000 times by punters as far afield as Canada and Taiwan,” notes the report. “Thanks to its growing fanbase, this has been its best year yet, hitting one million unique users and 8.2 million visits in total.”
