Science for Glass Eel Fisheries Management: How to Define TAC in France?

To tackle the low level of European eel stock, the European Union Council has adopted in 2007 a regulation for establishing measures for the recovery of the stock of European eel. In application of this regulation France established an eel management plan that includes, among others, measures to decrease glass eel fisheries mortality by 60% in 2015. It has been decided to set up a total allowable catch system to achieve this mortality target.

A scientific experts panel has been constituted to estimate TAC given the management target and the expected recruitment level. We describe methods used (i) to estimate mean exploitation rate during reference period using catch and recruitment series and (ii) to predict future recruitment level. A Bayesian model has been designed to cope with the variability in past exploitation rate due to environmental and economic conditions and with the uncertainty in recruitment prediction, particularly the possibility of alternative future (unchanged decreasing trend or regime shift and possibly increasing trend). The TAC really adopted and the actual recruitment and exploitation rate level are compared to the prediction made. We finally discuss the role of scientists, managers and fishers and the importance of exchanges between them in this management process.