The potential of marine reserves for the management of Northern Cod in Newfoundland
The potential of marine reserves for the management of Northern Cod in Newfoundland
复制标题
纽芬兰北部鳕鱼管理海洋保护区的潜力
DOI：
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发表时间：
2000
影响因子：
1.5
通讯作者：
C. Walters
中科院分区：
文献类型：
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作者：
S. Guénette;T. Pitcher;C. Walters
海洋保护区（禁止开发海洋生物的区域）应能更好地应对管理错误，如高估种群、捕捞努力量控制不足和渔获量统计不准确。我们采用了一个详细的人口模型，探讨利用海洋保护区，以保护鳕鱼种群过度开发。20世纪80年代纽芬兰东海岸的北方鳕鱼，在生物量低，但之前的主要崩溃，被用作案例研究。我们提出了两个问题：海洋保护区是否能阻止1992年的崩溃，以及保护区与其他管理措施相比如何？该模型是年龄和空间结构，包括招聘功能（Beverton和霍尔特型）。通过纳入靶细胞（吸引部位）来模拟迁移，靶细胞对每个年龄和一年中的每个月都有特异性。目标细胞周围的随机运动决定了鱼类如何扩散以形成沿着由目标细胞定义的季节性轨迹移动的空间分布。根据三类渔具（拖网、刺网、诱捕器）捕捞努力量的时间和空间分布的历史数据，对捕捞进行了校准。海洋保护区单独或与临时关闭一起建模。对于20世纪80年代低鳕鱼生物量，如果单独使用，只有大的储备（80%的渔场）才能防止崩溃，并允许鳕鱼种群重建。然而，这些非常大的保留区会减少剩余渔场的单位努力量渔获量，并可能导致渔具投资增加，从而使保留区的目的落空。在鳕鱼生物量低的情况下，保留区必须同时减少捕捞能力。当使用中等规模的储备（20%），暂时关闭拖网和刺网成功地防止崩溃和重建的股票。
Marine reserves (areas closed to exploitation of marine life) should allow better resilience to management errors such as overestimation of stocks, inadequate control of fishing effort, and inaccurate catch statistics. We employed a detailed population model to explore the use of marine reserves to protect cod populations from overexploitation. The northern cod of the east coast of Newfoundland in the 1980s, at low biomass but prior to the major collapse, was used as a case study. We asked two questions: Would marine reserves have prevented the 1992 collapse, and how would reserves compare with other management measures? The model is age- and spatially-structured and includes a recruitment function (Beverton and Holt type). Migrations were simulated by inclusion of target cells (attraction sites), which were specific for each age and month of the year. Random movements around target cells determined how fish spread to form a spatial distribution that moved along the seasonal trajectory defined by the target cells. Fishing was calibrated from historical data on temporal and spatial distribution of effort for three types of gears (trawl, gill net, trap). Marine reserves were modeled alone or in conjunction with temporal closures. For the 1980s low cod biomass, if used alone, only large reserves (80% of the fishing grounds) would have prevented the collapse and allowed the cod stock to rebuild. However, these very large reserves would have reduced the catch per unit effort on the remaining fishing grounds and possibly triggered an increase in investment in gear, defeating the purpose of the reserve. At low cod biomass, reserves must be accompanied by a reduction in fishing capacity. When used with reserves of moderate size (20%), temporal closures to trawls and gill nets succeeded in preventing a collapse and rebuilding the stock.