Over 1 million dams and culverts (tunnels that encircle rivers passing under roads) block the movements of fish and other wildlife in Europe. Scientists estimate that less than 1% of catchments in the U.K. are free of obstruction. A report released in 2020 showed the effect this trend is having worldwide: a more than 75% decline in the abundance of 247 migratory fish species globally since 1970.
Click here for original story, Fish passes can reconnect species with habitats blocked by dams. Here’s how they work
Source: Phys.org