We've updated our Privacy and Cookies Policy
We've made some important changes to our Privacy and Cookies Policy and we want you to know what this means for you and your data.
Have you heard of the fish doorbell?
Image source, Getty Images
You might think doorbells are just for humans but in the Dutch city of Utrecht there's one for fish too!
The Netherlands is a country with lots of canals for people, as well as fish, to travel along.
In spring the lock gates along these canals aren't opened much and this can make it difficult for fish to travel to their breeding grounds.
So the people in charge of the canals set up a digital doorbell - using an underwater camera live streaming to their website so they knew when to open the gates and let the fish through.
Image source, Getty Images
It's been so successful that the doorbell will return next spring too.
Anyone could watch the camera footage online and when they spot a fish at the gates they press the digital doorbell on behalf of the fish and alert the lock keeper. The keeper checks if there are enough fish there to open the gates and the fish can swim on their merry way.
The doorbell has been used thousands and thousands of times over the spring and people all over the world have been taking part and helping the fish.
Image source, visdeurbel
The underwater camera showed lots of different fish swimming through including bass, roach and pike. Eels, which are very rare, appeared in front of the camera a few times too.
The people running the fish doorbell say they're also using the camera images to find out more about the types of fish passing through so that they can help improve the quality of underwater life in the city.