Large-scale closed areas as a fishery-management tool in temperate marine systems : The Georges Bank experience
Large-scale closed areas as a fishery-management tool in temperate marine systems : The Georges Bank experience
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大规模禁渔区作为温带海洋系统渔业管理工具：乔治银行的经验
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
L. Hendrickson
中科院分区：
文献类型：
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作者：
S. Murawski;R. Brown;Han;P. Rago;L. Hendrickson
自 1970 年以来，季节性禁渔区一直是新英格兰水域渔业管理的一个组成部分，但在 1994 年之前，对其设计目的的底栖鱼类种群的保护影响有限。从 1994 年 12 月开始，乔治浅滩和新英格兰南部对底栖鱼类产卵和幼鱼生产具有重要历史意义的三大区域（总面积达 17,000 平方公里 2 ）全年禁止使用任何能够保留底栖鱼类的渔具（拖网、扇贝挖泥机、刺网、钩钓）。在接下来的五年中，禁区对减少枯竭的底栖鱼类种群的捕捞死亡率做出了重大贡献。封闭区域的设置为浅层定居的鱼类（主要是比目鱼、鳐鱼和其他杂项）和双壳类软体动物提供了最大程度的全年保护。尽管捕捞捕捞活动对大西洋鳕鱼、鳕鱼和黑线鳕等洄游年龄组的全年保护有所减弱，但开放地区和乔治浅滩加拿大部分地区的额外新规定也有助于观察到的鱼类种群捕捞死亡率的下降。由于底栖鱼（尤其是比目鱼）的副渔获物，这些区域禁止使用为海扇贝（Placopecten magellanicus）设计的挖泥设备。 1994-1998 年间，封闭区内的扇贝生物量增加了 14 倍。 1998 年 7 月，封闭区域的扇贝总生物量和可收获扇贝生物量分别是邻近开放区域的 9 倍和 14 倍。根据砾石/卵石沉积物类型中底栖鱼幼鱼的出现模式，部分封闭区域被指定为特别令人关注的栖息地。 1999 年，管理人员重新开放了部分封闭区域进行海扇贝疏浚，但对渔具和捕捞区域进行了限制，以尽量减少底栖鱼类副渔获物以及对砾石底质上的幼鳕鱼和黑线鳕的影响。这些重新开放的结果鼓励管理人员考虑正式的扇贝“区域轮换”计划，旨在提高每名员工的产量。尽管根据新英格兰南部黑线鳕的季节性产卵地和黄尾鲽 (Limanda ferrugineus) 的分布来选择关闭区域，但事实证明，乔治滩大部分地区的关闭是导致更有效地保护众多资源和非资源物种的一个重要因素。未来，除捕捞死亡率降低以外的其他因素，包括提高幼体产量和保护育苗区和产卵集中度的最佳布局，可能会很好地影响禁区边界的选择。
Seasonal closed areas have been an element of fishery management in New England waters since 1970 but before 1994 had limited impact on the conservation of groundfish stocks for which they were designed. Beginning in December of 1994, three large areas of historic importance to groundfish spawning and juvenile production on Georges Bank and in Southern New England, totaling 17,000 km 2 , were closed year-round to any gears capable of retaining groundfish (trawls, scallop dredges, gill nets, hook fishing). In the ensuing five years, the closed areas contributed significantly to reduced fishing mortality of depleted groundfish stocks. Placements of the closed areas afforded the greatest year-round protection to the shallow-sedentary assemblage of fishes (primarily flounders, skates, and miscellaneous others) and bivalve molluscs. Although the closures afforded less year-round protection to migratory age groups of Atlantic cod, Gadus morhua, and haddock, Melanogrammus aeglefinus, additional new regulations in open areas and in the Canadian portions of Georges Bank also contributed to the observed reductions in stock-wide fishing mortality rates. The areas were closed to dredge gear designed for sea scallops, Placopecten magellanicus, because of groundfish by-catch (particularly of flounders). Scallop biomass increased 14-fold within the closed areas during 1994-1998. In July 1998, total and harvestable scallop biomasses were 9 and 14 times denser, respectively, in closed than in adjacent open areas. A portion of the closed areas was designated a habitat area of particular concern on the basis of patterns of occurrence of juvenile groundfish in gravel/cobble sediment types. Managers reopened portions of one closed area to sea-scallop dredging in 1999, but restrictions on gear and areas fished were used to minimize groundfish by-catch and impact on juvenile cod and haddock on gravel substrates. Results from these reopenings have encouraged managers to contemplate a formal 'area rotation' scheme for scallops intended to improve yield per recruit. Closures of large portions of Georges Bank have proved to be an important element leading to more effective conservation of numerous resource and nonresource species, despite selection of the closed areas on the basis of seasonal spawning grounds of haddock and the distribution of yellowtail flounder, Limanda ferrugineus, in southern New England. In the future, factors other than fishing mortality reduction, including optimal placement to enhance larval production and to protect nursery areas and spawning concentrations, may well influence the selection of closed-area boundaries.