A couple of months ago, we wrote about a remarkable online “fish doorbell” or visdeurbel that allows spawning fish to swim through the canals of Utrecht in the Netherlands unobstructed by the Weerdsluis lock.
The system is comprised of an internet-connected underwater camera located next to the lock gate. Members of the public can view the camera’s live feed (some stills from this feed are featured in the photo above) through an app at any time, and if users notice that there are several fish outside the gate, they can notify the lock operator by ringing a digital doorbell on the app. The operator then confirms whether there are indeed a number of fish present and will manually open the gate to let them pass.
Mark van Heukelum, the Dutch ecologist who came up with the clever design, was happy to report that the response to the doorbell was immediate and spread far wider than just Utrecht or even the Netherlands. Within two weeks, 735,000 people from all over the world including Canada, Germany, Spain, and Taiwan had visited the website and the doorbell had been rung over 32,000 times.
Van Heukelum reports that he “was jumping in [his] living room,” when he realized how well the public was responding. “Of course we hoped that there would be attention and we were sure that at least in Utrecht people would be interested in the project, but before we knew it, it really took off.”
In fact, so many people rang the doorbell that the lock manager had to establish a regular schedule of opening the lock once in the morning and once in the evening, and another time throughout the day whenever there were larger fish gatherings present.
The doorbell’s initial function is working splendidly, but there are other benefits to this design as well. Now, researchers can gather data on Utrecht’s fish population and can conclude that the canal is an important migration route. The Utrecht municipality also confirmed, through the appearance of eel and ide river fish, that the Utrecht canals certainly connect the Vecht and Kromme Rijn and are part of a river system. In addition, the camera and doorbell highlight the often-forgotten presence of underwater nature in the canals that run through Utrecht and in other cities.
Many who live in these cities get accustomed to seeing canals only as historical monuments or convenient routes for boats to pass, but it’s important to remind people of their connection to different rivers and of the biodiversity that depends on them.
For now, the doorbell isn’t in service because the lock has returned to being opened regularly for the summer months. The municipality of Utrecht reports that the bell was rung over 100,000 times since its installment at the end of March 2021, and has stated that it will be back in use in 2022.
Source Image: Visdeurbel.nl