Very few of world’s rivers undamaged by humanity, study finds

Rivers are biodiversity hotspots but pollution, dams and invasive species have caused havoc

Rivers in which fish populations have escaped serious damage from human activities make up just 14% of the world's river basin area, according to the most comprehensive study to date.

Scientists found that the biodiversity of more than half of rivers had been profoundly affected, with big fish such as sturgeon replaced by invasive species such as catfish and Asian carp. Pollution, dams, overfishing, farm irrigation and rising temperatures due to the climate crisis are also to blame.