A new Europe-wide project has identified that the density of barriers in rivers is much higher than previously thought, with up to one structure per kilometre blocking the path of migrating fish.
An example of a barrier along the River Itchen
Hundreds of thousands of human-made barriers are scattered across the continent’s rivers – for example weirs, dams, culverts, fords and sluice gates. They can block the natural swim-ways of migrating fish, such as eel and salmon.
Researchers, including academics from the University, have found that the number of barriers recorded currently may represent as little as three per cent of the total existing in Europe.
The Adaptive Management of Barriers in European Rivers (AMBER) study collected all available data on river barriers within Europe and surveyed a total of 1,000 km of rivers.
To help map where barriers are, scientists are inviting people to get involved by logging information about barriers near them with a newly-developed, free smartphone app called Barrier Tracker.
Dr Jim Kerr, of Engineering and the Environment, says:
“Researchers from AMBER were shocked to find there were so many barriers in most rivers. But the good news is that with the use of mobile phone technology and this new app, people can help build a much more accurate picture of the obstacles fish are encountering and help contribute towards river conservation.”
The launch of the app coincided with World Fish Migration Day (21 April 2018), aimed at creating awareness of the importance of open rivers and migratory fish.
Fisheries scientists from the University ran a day-long interactive stall at Mottisfont House and Gardens National Trust site in Hampshire to promote this and the launch of the AMBER Citizen Science portal.
