Microchip study hopes to save eels

European Eels are being microchipped in an attempt to better understand their movements outside the breeding season. A study by the Wildfowl and Wetlands Trust (WWT) will track the eels that use the Severn river system at Slimbridge WWT as they return to the sea to breed. The information is hoped to shed light on how the eels are using the reserve, and at when they leave the site to return to the sea to breed.

The Severn is a highly important river for European Eels – having hatched in the Sargasso Sea the young drift thousands of miles across the Atlantic, with millions ending up in the Severn where they mature in freshwater. Traditionally, these eels would reside in the wetlands of the Severn Vale before completing their life cycle by returning to the ocean to spawn and then die. However, with much of this habitat being lost or degraded, and the eels' movements hindered by pumps and sluices along the waterways, the species is in decline and is now on the Critically Endangered list.

The study is part of a broader eel conservation project being undertaken by WWT in partnership with Bristol Water. The project aims to improve eel access around the site, and will eventually extend to the wider Severn Vale in an effort to help the species. WWT Head of Reserves Management Emma Hutchins said: "WWT is famed for its conservation work with endangered migratory birds around the world, but the most endangered species living on our nature reserves is the European Eel, also a master of long distance.

"As one of the biggest wetland areas within the Severn Estuary under conservation management, Slimbridge is an ideal place to enhance for eels and centre this conservation project. Numbers of glass eels (youngsters) returning to the UK have decreased by 95 per cent in the past 40 years and they urgently need our help."

As eels leave the Severn, the chips will automatically set off a reader placed on the main ditch, confirming when each individual has started to migrate. The microchips can also be read by a hand-held scanner if the eels are caught in future, enabling researchers to understand how they're using the ditches and pools Slimbridge, in order to track individual movements.