MANAGING GROWTH OVERFISHING WITH MULTIANNUAL COMPROMISE STRATEGIES

Most of the Northeast Atlantic stocks are currently fished above the b iological reference points (e.g., F-max). In attempting to achieve suc h targets, advisers and managers have faced two main problems. First, it is impractical to (i) simultaneously maximize yields, stabilize fis heries, and safeguard stocks and (ii) optimize both short-and long-ter m outcomes for the industry. Second is the lack of predictability, sev eral years ahead, in factors influencing decisions. This study address es these twin issues by exploring the relative performances of various multiannual and compromise (or composite) management strategies. Mult iannual fishing efforts are set in advance for a ''resolution'' period of several years, at the end of which they are updated. They are calc ulated to satisfy a prior weighted compromise amongst three criteria: (i) minimizing fishing effort variability, (ii) minimizing catch varia bility, and (iii) reaching a ''mobile target:'' the latter is defined with a second weighted compromise between the long-term target and the fishing effort at the beginning of the resolution period. A safe and optimal balance between all the short-and long-term fishery outcomes i s found with a 5-year resolution period, during which the mobile targe t is split into 40-60% of the long-term target, and 60-40% of the fish ing effort at the start of the resolution period, while criteria i, ii , and iii are weighted equally.