In Utrecht, a city in the heart of the Netherlands, a unique "fish doorbell" system has been implemented, allowing online viewers to play an active role in aiding fish migration.
The system, now in its fifth year, operates via a livestream camera positioned underwater at the city's Weerdsluis lock.
This camera transmits live footage to a dedicated website, where viewers from across the globe can observe fish as they attempt to navigate the lock during their springtime journey to shallower spawning grounds.
The process is remarkably simple: when a viewer spots a fish on the livestream, they click a button, capturing a screenshot that is then sent to the project organisers.
Once a sufficient number of fish are observed waiting at the lock, organisers notify a water worker who then opens the lock gates, allowing the fish to continue their upstream migration.
The site has attracted millions of viewers from around the world with its quirky mix of slow TV and ecological activism.
Much of the time, the screen is just a murky green with occasional bubbles, but sometimes a fish swims past. As the water warms up, more fish show up.
Without the help, native freshwater fish like bream, pike and bass can become backed up behind the lock and form easy prey for predators in the spring, when the lock is rarely opened for passing boats.
The bell is the brainchild of ecologist and concept developer Mark van Heukelum. He's been happily surprised at the response, with millions of people from around the world tuning in over the years.
“I guess the combination of a good cause, a beautiful story and just a simple idea generates all this attention," he said.
Anna Nijs, an ecologist with Utrecht municipality, was also amazed at the popularity of the concept around the world.
“We get a lot of fan mail from people who think it’s slow TV and they find it relaxing," said Nijs. Besides, “they appreciate that they can actually do something to help.”
