The European Eel (Anguilla anguilla) is an incredibly important, but often under-valued species in the Atlantic Area. It is essential to the economic viability of small-scale coastal fishing in Europe as well forming part of the traditional fishing economy in the UK.

The eel, like the salmon, lives alternately in freshwater and seawater, but opposite to the salmon the eel spends its adult life (yellow eel stage) in freshwater then swims down river where it is thought to migrate out to the Sargasso Sea to breed (silver eel stage). This mass spawning produces vast numbers of larvae, which drift/swim with the ocean currents across the Atlantic. These larvae will then reach the European coastline where they metamorphose and move up into the rivers during the spring (elver stage).

Recently there has been a massive decline in the number of eels arriving at European Rivers. Eel status was recently defined in the reports of the ICES/EIFAC working group as ‘outside safe biological limits’ with critical situations mainly in Northern Europe. This decline has been linked to factors in the freshwater environment including changing land use and increased numbers of impassable barriers as well as factors in the marine environment such as long-term alteration of the currents that young eels rely on to make their journey from the Sargasso Sea.

Due to this decline in eel populations across Europe, the Trust joined a pan-European partnership to attempt to provide a global solution to a global issue. This partnership ran a project called INDICANG, which examined and gathered data concerning eel populations across the Atlantic Arc. Little is known about this elusive creature, so the first aim of the project was to establish a monitoring system that can be used in rivers throughout Europe. Not only did the project focus on the eel numbers themselves, but it also investigated changing land use over time, fishing pressure, migration barriers and other factors that influence the freshwater stage of the eel life cycle. This information was then collated, assessed and disseminated to those involved in the management of eel populations.

INDICANG was launched in April 2004, and we worked closely with our European partners to create a conservation strategy for this creature whose presence has for many years has been largely taken for granted.

We are delighted that the Environment Agency also joined forces with us at a national level, and their assistance was largely co-ordinated by Miran Aprahamian who is not only a leading expert on eels, but also the principal fisheries scientist for the Agency. We also worked closely with the Eel Research Group based at Kings College, London who are provided expert advice and practical support.

The project also included gathering data on eel population for a number of South-West Rivers. This data has been used to target various eel sampling strategies looking at the three life history stages of the eel; elver, yellow and silver eels. We established eel monitoring at Slapton Ley and the catchment surrounding the Ley, through the support and assistance of the Field Studies Council. We also focused on the Tamar, Camel and Fowey catchments in Cornwall.

To examine the different life history stages of the eel requires a variety of different methods for their capture such as elver traps and fyke netting. Eels that have been captured can provide information concerning their length, weight and numbers which gives an indication on the health of the population within the river. As well as these surveys, information about eel numbers, sizes etc. from anglers is also vital to the project and helps towards learning more about this creature within our rivers.

Through the Westcountry Rivers Trust’s links with Dr Tony Bark and Beth Williams from the eel research group based at King’s College London, Dr Brian Knights based at Westminster University, Slapton Ley National Nature Reserve and the Environment Agency we established a successful elver trap (pictured) at Slapton Ley. This trap encourages migrating elvers to move up through the green brush and drop into the collecting vessel. These elvers can then be counted and measured, thus providing us with information about these new eel recruits of Slapton Ley and its surrounding rivers.