Quirky website that lets viewers help fish is a hit with millions

The Dutch city of Utrecht has installed a “fish doorbell” on a river lock that lets viewers of an online livestream alert authorities to fish being held up as they make their Migration to spawning grounds.

The idea is simple: An underwater camera sends live footage to a website. When somebody watching the site sees a fish, they can click a button that sends a screenshot to organizers. When they see enough fish, they alert a worker who opens the lock to let the fish swim through.

Now in its fifth year, the site has attracted millions of viewers from around the world with its quirky mix of slow TV and ecological interaction.

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 "doorbell" concept developer Mark van Heukelum has 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. 

They get a lot of fan mail from people who think it’s slow TV and they find it relaxing. Writers appreciate that they can actually do something to help.