Ireland’s rivers are too fragmented due to human activity according to Inland Fisheries Ireland at the launch of new European project called AMBER which aims to restore river connectivity. The project, which stands for Adaptive Management of Barriers in European Rivers, seeks to raise awareness of the problems posed by stream fragmentation, the pressures on freshwater ecosystems and the need for innovative solutions to restore river connectivity. All major rivers across Europe are disconnected from the sea to varying degrees as a result of barriers, with negative impact on many fish species.

A survey on the River Nore by Inland Fisheries Ireland found 500 instream structures currently in place. While not all of these structures are barriers to fish passage, the number indicates the extent of human activity on Irish rivers. Man-made barriers on rivers, such as dams or weirs, can delay or block the migrations of some of Ireland’s iconic migratory fish such as the Atlantic Salmon or European Eel. These species have in certain areas across Europe become extinct as a result. The less well-known Irish migratory species such as the Twaite Shad, a member of the herring family and the sea lamprey, are also affected.

The barriers which cause negative impact on the aquatic eco-system are often as a result of requirements for navigation, hydropower, irrigation, the provision of a drinkable water supply or for leisure purposes. The major hydroelectric schemes in Ireland have had an impact on the migration of adult Atlantic Salmon populations in the River Shannon, River Erne, River Liffey and River Lee. Studies by Inland Fisheries Ireland show that sea lamprey congregate and spawn downstream of large weirs on major rivers, even when spawning areas are available upstream. This means that the species does not spread as widely into headwaters and tributaries. Wide dispersal provides a safeguard for the species if a severe impact occurs in one tributary.

AMBER, which is a €6.2 million Euro multi-disciplinary research project, will see 19 partners from 11 countries, including Ireland, combine citizen science and cutting-edge technology to map the distribution of barriers and assess their effects on freshwater organisms. It will work with hydroelectric companies, water providers, NGOs, anglers and local authorities to restore river connectivity. The project will encourage citizens to become involved in efforts to reconnect Europe’s rivers by mapping the location of barriers and assessing their impacts with the help of a smartphone app.

Inland Fisheries Ireland is also currently working locally with stakeholders and other public authorities to address fish passage problems at barriers in a range of catchments. This includes removing the barrier, construction of a fish-friendly bypass channel or modifications to the structure to allow fish passage.

Dr. Cathal Gallagher, Head of Research and Development at Inland Fisheries Ireland said: “Inland Fisheries Ireland is committed to protecting, conserving and enhancing the aquatic eco-system in Ireland. We are delighted to work with our partners across Europe via this AMBER project which allows us to review river fragmentation and protect our natural capital.

Ireland is no different from our European neighbours in that our rivers face huge challenges. However AMBER recognises that barriers such as dams generate electricity and play an essential role in addressing water security and in supporting agriculture and industry. AMBER will help reconnect Europe’s rivers the smart way, knowing which barriers to mitigate and which ones to optimise.”

AMBER is funded under the EU Horizon 2020 programme of scientific research and has 19 partners in 11 member states. These cover academic institutions, hydropower companies, nature conservation organisations and state fisheries agencies.