Search

Project to increase eel population

PUBLISHED: 15:39 13 May 2008 | UPDATED: 20:23 05 July 2010

THE Environment Agency and RSPB are working together to improve the level of eel stocks at Minsmere because of the serious decline of the European eel in the UK and the rest of Europe.

THE Environment Agency and RSPB are working together to improve the level of eel stocks at Minsmere because of the serious decline of the European eel in the UK and the rest of Europe.

Tomorrow 2,000 elvers are being released at the RSPB Reserve at Minsmere. The reserve has the ideal habitat for the elvers of shallow lakes with reed-beds, connection to a river system and no commercial fishing.

This will be of benefit for conservation species such as the bittern and otter and will increase numbers of eels reaching maturity and migrating to the Sargasso Sea for spawning.

All European eels share the only known spawning ground in an area of the Sargasso sea, south of Bermuda. Eel larvae (known as leptocephalus larvae) follow the Gulf Stream and North Atlantic Drift to return to Europe metamorphosing into glass eels when they reach the continental shelf. Glass eels are attracted to freshwater and enter UK rivers in Spring, historically in great numbers, especially on the West Coast.

Glass eels become pigmented and metamorphose into elvers, spending a number of years in rivers and lakes, feeding and growing. After an average of six years for males and nine years for females, eels begin to mature, stop feeding and become silver in colouration. Silver eels swim downstream towards the sea to begin the long migration of 5500 km back to the Sargasso Sea, where they will spawn and die.

Numbers have dropped dramatically in the past few years and are now thought to be about five per cent of 1980s' levels. All life stages of eel are of ecological and economic importance and it is vital that action is taken now to prevent their extinction. The Environment Agency has prepared an Eel Management Plan (EMP) for Anglian Region to assess the status of eel stocks and actions needed to improve survival and distribution of all life stages. The objective is to increase the numbers of adult silver eels able to migrate to the Sargasso Sea.

The first stage in implementing the EMP is underway in the region. Glass eels are being monitored in special traps to determine how many are migrating upstream. Barriers to migration are being assessed for both elvers and silver eels. 'Quick fixes' with materials assisting elvers to pass over weirs and other obstructions are being installed.

The very low numbers of elvers returning to the East Coast means much habitat is under used. Most elvers return to the West Coast so there is an opportunity to transfer elvers from the Severn Catchment where many would otherwise be taken by the commercial fishery or die from overcrowding. Stocking these elvers at suitable sites in Anglian Region where there are very low densities of eels may be an important strategy for eel conservation. RSPB reserves such as Minsmere will provide ideal sites for eel nurseries.

Most Read

Most Read

Latest from the Lowestoft Journal

Hot Jobs

Show Job Lists