You probably cross rivers every day without realising it. Beneath the concrete underfoot are culverts – tunnels installed under roads and railways that allow rivers to pass from one side to the other. Like bridges, culverts allow people to cross rivers, but unlike bridges, culverts often don’t allow the fishes living in those rivers to cross roads.
Why worry about fishes crossing roads? A recent study found that, on average, the abundance of 247 migratory fish species has fallen by 76% worldwide since 1970. The hundreds of thousands of dams that fragment rivers around the world are a major cause of these declines. Removing these dams, the report urged, could restore the pathways that migratory fishes take and help their populations rebound. MORE
Header image: Dale Higgins, Author provided.