辽东湾海蜇捕捞管理模式探讨

文章以辽东湾海蜇捕捞为例,探讨“公地悲剧“的协调问题.发现,许多人误以为海蜇捕捞冲突是源自共用品造成的“市场失灵“,实际上,海蜇资源远不属于“共用品“,反而更接近于“私用品“.海蜇捕捞冲突是一个“公地悲剧“问题,要解决这一问题,核心在于产权,必须以此作为讨论海蜇管理相应政策建议的出发点.最后,文章认为基于产权的渔业共同管理模式是一种有效的方案.     

辽东湾北部海区初级生产力与渔业资源的关系

本文以2002年辽东湾北部海区的调查数据为主,参考部分2000～2003年的数据,对辽东湾北部海区的初级生产力进行了估算,为了分析和讨论的方便,将辽东湾北部海区人为划分为三部分,东部的初级生产力最高,8月份平均为222 88mg·C/m2·d;中部区域初级生产力最低,10月份为46 39mg·C/m2·d。不同区域的初级生产力的差距较大;如单独估算20～30站位的初级生产力,则分别为:4月平均192 43mg·C/m2·d,6月482 69mg·C/m2·d,7月274 8mg·C/m2·d,9月252 52mg·C/m2·d,远远高于各站位的平均值。辽东湾北部海区的初级生产力具有明显的区域特征,与渔业资源关系密切。     

渔业管理方法及制度效应——交易成本的视角

目前渔业管理方法众多，每种方法的成败也有着不同的评价标准与目标。文章对四种主要的管理方法进行分析并简要概括了优势和不足，在此基础上用信息成本、协调成本、战略成本对这四种渔业管理方法进行评估，指出成功的渔业管理需要将这些管理方法本身固有的成本和收益、优势和劣势与特定渔业的具体情况相匹配。     

Fishery indicators during a predictable aggregation of Atlantic sharpnose sharks Rhizoprionodon terraenovae in the southern Gulf of Mexico: An alternative to assess a heterogeneous data‐poor fishery

Small‐scale fisheries in the southern Gulf of Mexico that catch Rhizoprionodon terraenovae (Richardson) are heterogeneous and data‐poor. Fishery‐dependent monitoring was conducted from 2010 to 2017, including a target season during an aggregation of this species to estimate data‐poor fishery indicators. During the target season, the average sizes for females and males (95.3 and 89.8 cm total length, respectively) were recorded, a global male sex bias (1:1.7), the highest percentage of mature sharks for all years (>89%), the highest values of CPUE (20.1 sharks/day) and size‐selectivity higher than the size at maturity. The spawning potential ratio was over 0.6 (reference point of 0.71) in the combined (target and non‐target) and target seasons for all years, which suggests that the fishery stock is not healthy. Annual assessment of this fishery can be carried out through monitoring during the target season, where management is more feasible to implement.