Matthew Newton, a scientist at Glasgow University, used state-of-the-art radio tagging technology in a two-year study of salmon in Scotland as they migrate upriver to breed. He discovered that barriers such as weirs and dams can delay a fish’s progress for up to a month, and in some cases prove uncrossable. He found that 10 per cent of fish failed to pass each barrier.
The environmental and evolutionary biology PhD student will publish the results next year in his thesis.
He says salmon and trout populations in rivers with several of these hurdles, sometimes as many as eight, could be under serious threat.
Scotland on Sunday