Challenges to reconcile conservation and exploitation of the threatened Anguilla anguilla (Linnaeus, 1758) in Santo André lagoon (Portugal)

Abstract The adoption of the EC Regulation 1100/2007 for the recovery of the European eel required EU member states to implement and periodically report on their Eel Management Plans (EMPs) with the goal of achieving at least 40% of the silver eel escapement relative to the best estimate of escapement that would have existed if no anthropogenic influences had impacted the stock. The specific measures to achieve such a goal have spurred a harsh debate among the different stakeholders with the need to mediate among multiple conflicting interests. In this investigation the study of the dynamics of the eel fishery in the Santo Andre Lagoon, a small-scale fishery in the southwest of Portugal, is presented. Through the description of the management structure, the analysis of 40 years of catch and effort data, and the analysis of socio-economic data, the existing enforcement and the way forward is discussed. Day-to-day logbooks of catch and effort data from five professional fishermen, for two fishing seasons (that is, 2011/2012 and 2016/2017), and surveys to the community, were used to independently estimate total harvest and income of the eel fishery in Santo Andre Lagoon, and the perception of the fishermen toward regulation and management. The results showed that both catch per unit effort and fishing yield increased during the study period and now ranges between 68 and 169 kg/ha, with eel fishing making a significant fraction of the fishermen's revenue. Although the existing regulation does not satisfy the fishing community, their disagreement decreased during the studied period. The analysis of the fisheries management in the lagoon and its impact on eel harvesting and, on the stock, revealed opportunities to adjust the set of regulations enforced at the national level under the Portuguese EMP to the specific context of the Santo Andre Lagoon. Specifically, a co-management approach would promote legitimacy and contribute to a better acceptance of the regulations by the fishing community.