The fish migration season is upon us, which means one thing: Utrecht’s fish doorbell (visdeurbel) is back up and running for the season. Users can now access the livestream online and press the online doorbell to alert the lock-keeper in Utrecht that there are fish ready to come through the lock.
“At this time of year, it is mainly the ide and pike that are migrating,” creator of the fish doorbell and aquatic ecologist Mark van Heukelum told BNNVARA. Spotters using the website can already see many different types of fish migrating through the canals of Utrecht.
Last year, the bass and sea bream fish were the most common, according to the underwater camera which captures the creatures lurking in the city’s waters. There were also several rare types of fish spotted in the canals by people on the internet, including the catfish, which is a large predatory fish that has migrated significantly in recent years.
According to its creators, the fish doorbell has proven itself to be incredibly popular since its creation. In 2023, figures show that the website was visited no less than 8,2 million times, and the doorbell was rung a total of 105.000 times to help thousands of fish migrate through the canal network. The majority of visitors to the site came from Germany and the United States.
The reason behind the fish doorbell is that opening the lock is an intense manual job that has to be undertaken by the lock-keeper. By having the doorbell, the lock-keeper is only alerted when a significant number of people spot a large number of fish, thereby shrinking the workload of the lock-keeper.