Why care about eels?
Eels play an important socio-economic and ecological role in many European countries. Figure 1 shows that recruitment of glass eels has fallen to below 5% of peak levels (measured from the 1950s onwards) and Figure 2 shows that catches of yellow and silver eels have declined from 40,000t in the 1960s to less than 10,000t today. The stock is judged to be outside safe biological limits and the EU’s Eel Recovery Plan aims to maximize silver eel production and escapement to the sea to ensure that enough eels reach the spawning grounds and sufficient larvae are produced to reverse the stock’s decline.
Figure 1. Recruitment of glass eels over last 50 years
Figure 2. Eel catches over last 50 years
However, very little is known about the life and spawning success of silver eels once they escape to the sea. In this respect, efforts to conserve and manage eel stocks are ‘blind’ because the effectiveness of management measures in rivers and estuaries to ensure successful escapement of silver eels to the sea can only assume that this contributes proportionately to their eventual reproductive activity.
eeliad is a scientific research project that aims to resolve some of the mysteries of eel biology, and to use this information to help conserve European eel stocks. The project will integrate and take advantage of significant recent improvements in techniques such as animal tracking, genetics and advanced mathematical modelling. The techniques will be combined in a large-scale field programme that will run between 2008 and 2011 and will be linked to studies and observations undertaken in other research and monitoring projects in freshwater and brackish environments to enable a comprehensive understanding of the life-cycle of eels to be developed.
