REFERENCE POINTS: A BIO-ECONOMIC MODEL BASED APPROACH

摘要

The concept of reference points (RPs) is closely connected to the management objective which, by also involving economic and social issues, may not be restricted to the sole biological maximization (maximum sustainable yield). It is possible to definedifferent RPs for each aspect of management or to identify a single RP aimed at ensuring the sustainability of the system, no longer limited to biology, but affecting environmental, economic and social features that involve the state of system as a whole. The latter is described as a multicriteria RP. This paper briefly outlines the main RPs obtained by applying the bioeconomic optimization models of effort and effort-catch, with specific reference to the Gordon-Schaefer model, which clearly derives from the theory of population dynamics. The debate about the effectiveness and the efficiency of both the indicators and the RPs that are potentially useful in monospecific fishery is here conducted with respect to the multispecific character of Mediterranean fishery and the different selectivity of employed gears. Accordingly, as regards the Mediterranean context, we recommend the adoption of a multicriteria approach based on bio-economic optimization models which, by introducing a number of constraints,would allow the definition of the actual state of the system as well as specific management targets.