31 March 2015

International effort sheds light on Atlantic salmon decline

French and English scientists unite to save Atlantic salmon at the GWCT's Morfish Conference in WarehamAn international conference jointly organised by the Game & Wildlife Conservation Trust (GWCT) and the French Institut National de la Recherche Agronomique (INRA) in Wareham, Dorset this month marked the end of the three year collaborative EU Interreg funded MorFish (Monitoring for Migratory Fish) Project, which included the investigation of the dramatic 70 per cent decline of Atlantic salmon observed in recent years.

Attended by more than 90 delegates from across Europe, the conference brought together key players involved in salmon monitoring and management and shared the results of this cross-border collaborative project. A crucial focus of the project was to improve and align the individual and population salmon monitoring facilities on the River Frome in Dorset, the Scorff in Brittany and Oir in Normandy, extend their long term data sets and to take on the challenging task of interrogating 40 years of data which has been collected by the GWCT in the UK and INRA in France.

The fascinating conference, which was chaired by Paul Knight, Chief Executive of the Salmon and Trout Association, included talks by some of the most eminent salmon experts across Europe with topics ranging from the findings emerging from examining fish scales to the extraordinary number of obstructions in rivers which could be influencing fish migration. A key aim of the conference was to highlight the potential need to set conservation limits to safeguard salmon populations into the future.

Dr Jean Marc Roussel from INRA explained how the French anglers collect between two and three thousand scales from individual fish they caught each year with a total of around 50,000 of these scales now held in the laboratory. The study of growth structure from these scales shows significant changes in freshwater and marine life of adult salmon over the last 40 years. INRA and its local partners also analyse the evolution of salmon populations on the river Scorff and Oir; about 30,000 individuals were monitored over the past 3 years. The microchemistry of tissue samples from these fish show that trophic levels have increased and this might potentially impact on juvenile salmon, particularly their growth and could be a direct result of nitrates entering watercourses from agricultural land.

Dr Stephen Gregory one of the GWCT fishery scientists explained to delegates how the collaborative project has been aligning and interrogating the long-term salmon and environmental data sets collected by GWCT and INRA on the Rivers Frome, Scorff and Oir. He explained, “Through the Morfish project we have made significant headway into two projects, which investigated both the possible environmental drivers that are changing parr lengths, such as water temperature and flow as well as investigating how to improve the monitoring of adult salmon using state-of-the-art resistivity counters with video verification.”

These two projects alone will provide original contributions to the scientific literature on salmon and hold great promise for improving monitoring on European salmon rivers by transferring our new modelling tool to the many rivers using fish counters.

Bénédicte Valadou who leads the development of management plans for migratory fish for ONEMA and attended the conference commented: “The MorFish project is an excellent example of cooperation which highlights the precious data collected regarding salmon populations. In order to understand the reasons for the decline in migratory fish populations in most rivers, it is necessary to continue collecting data in the same way so that they are compatible and can be analysed at the same time. Moreover, it is essential to secure and back up the information already collected because these long datasets are the fruit of many years’ work.

“The other asset of this project is its funding method, via EU Interreg IVA Channel funding, which enables cooperation between bordering countries which have rivers with similar characteristics. The multiplication of such projects encouraging collaboration and finding solutions to shared problems will increase the coherence of the various studies carried out on both sides of the North Atlantic. Already, the existence of tools such as Index Rivers around the world helps to nurture the dream of closer collaboration between researchers and managers working on migratory fish. A concurrent implementation of projects on this scale in different areas would help to make this become reality and this in turn would facilitate dialogue between national managers.”

Research carried out on the river Frome by the GWCT researchers at the Salmon & Trout Research Centre at East Stoke, has played a pivotal role in identifying how environmental conditions in freshwater affect the survival of salmon at sea. Over the past 3 years the scientists have collected information from 60,000 salmon parr, 15,000 salmon smolts as they leave the river for the sea and 4000 adult salmon and by using the technically advanced monitoring equipment they are able to record their return back to the river two or three years later.

Dylan Roberts, the MorFish project manager and Head of GWCT Fisheries said, “Although the MorFish project is coming to an end we will continue our important research on the River Frome to even further understand why numbers of Atlantic salmon returning to our rivers have declined so markedly over the last 40 years. This continuing decline has serious implications for the survival of the species as well as the angling industry that contributes many billions a year to countries around Europe. The MorFish project provided us with resources to upgrade and align our data collection facilities on the Frome, Scorff and Oir; continue our data collection and employ a specialist analyst to interrogate our long term data sets. A better understanding of the reasons for the decline will ensure their sustainable management.

“As well as maintaining our own research on the River Frome, we are keen to continue our collaborative work with INRA in France. Comparing our data on Atlantic salmon populations has enabled us to compile a database of nearly 100,000 individual salmon parr records with associated environmental and biological data as well as developing a suite of statistical models to investigate whether environmental shifts have caused changes in parr lengths. The research has also enabled us to compare lamprey survey methods with France and to assess and compare thin lip mullet movement.

“The work that we do on these rivers feeds into an international network of Index Rivers who collect detailed information each year on both juvenile and adult salmon populations. This information is used to better manage salmon stocks locally by providing information for the Environment Agency (EA) in England and ONEMA the National Agency for Water and Aquatic Environments in France to better manage their salmon conservation limits on each river and also nationally to government through the Centre for Environment, Fisheries & Aquaculture Science agency (Cefas) and INRA in France. This information is then used by the North Atlantic Salmon Conservation Organization (NASCO) and International Council for the Exploration of the Sea (ICES) who provide a global perspective and advice to governments on the status and management of their salmon stocks.”

The presentations and posters from the conference will shortly be available on the project web site www.morfish.org.uk

END

Photocaption: French and English scientists unite to save Atlantic salmon at the GWCT's Morfish Conference in Wareham.

Notes to editors:

The MorFish project is a collaboration between GWCT and INRA fisheries scientists who have been collecting data on Atlantic salmon and other migratory fish for up to 40 years. The project is funded through the EU’s Interreg IVA Channel programme.

The Game & Wildlife Conservation Trust is an independent wildlife conservation charity which has carried out scientific research into Britain’s game and wildlife for the past 70 years. We advise farmers and landowners on improving wildlife habitats and we lobby for agricultural and conservation policies based on science. We employ 22 post-doctoral scientists and 50 other research staff with expertise in areas such as birds, insects, mammals, farming, fish and statistics.  We undertake our own research as well as projects funded by contract and grant-aid from Government and private bodies.   The Trust is also responsible for a number of Government Biodiversity Action Plan species and is lead partner for grey partridge and joint lead partner for brown hare and black grouse. For Information, contact: Morag Walker – Head of Media, Telephone – 01425-652381 (direct 01425-651000) Mobile – 07736-124097    www.gwct.org.uk

The European Interreg IVA France (Channel) – England Programme 2007-2013 is the IV generation of the Interreg programme between France and England.  Around the Channel, French and English cross-border territories share common challenges.  Since 1990, the European Union has run the Interreg programme (strand A) which subsidises projects with cross-border partners willing to work together. Each border area thus becomes a forum for exchanges and orchestrated efforts between European neighbours. The programme has a total of 173.5 million euros in grant available through the European Regional Development Fund (ERDF).

MorFish

MorFish conference