The Fish Doorbell

“There is a canal in Utrecht where multiple varieties of fish spawn. Due to human needs, some parts of the canal had to be closed periodically so fish pooled together in the area. Once the gates were open, predators on the other side were basically served a buffet of the unsuspecting. Visdeurbel is the fix. Spot a fish, ring the doorbell, grant safe passage. Very fun, seasonal internet activity.”