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首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >A cold oceanographic regime with high exploitation rates in the Northeast Pacific forecasts a collapse of the sardine stock
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A cold oceanographic regime with high exploitation rates in the Northeast Pacific forecasts a collapse of the sardine stock

机译：东北太平洋一个寒冷的海洋学政体，高开采率预测沙丁鱼种群将减少

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摘要

The oceanographic conditions in the north Pacific have shifted to a colder period,Pacific sardine (Sardinops sagax) biomass has de clined precipitously in the California Current, the international sar dine fishery is collapsing, and mackerel (Trachurus symmetricus and Scomber japonicus) are thriving. This situation occurred in the mid-1900s, but indices of current oceanographic conditions and the results of our acoustic-trawl surveys indicate it likely is recurring now, perhaps with similar socioeconomic and ecological consequences. Also alarming is the repetition of the fishery's response to a declining sardine stock—progressively higher exploitation rates targeting the oldest, largest, and most fecund fish. Furthermore, our data indicate the recent reproductive condition of sardine is poor, and their productivity is below modeled estimates used to derive the current fishery-exploitation rates. Consequently, the sardine population has been reduced to two cohorts that are unlikely to produce an appreciable new cohort. Thus, a near-term recovery of this important stock is unlikely, depending on the return of warmer oceanographic conditions, reduced pressure from mackerel species, and perhaps the adoption of a more precautionary strategy for managing the residual sardine population.
机译：北太平洋的海洋条件已转变为一个较冷的时期，太平洋沙丁鱼（Sardinops sagax）的生物量在加利福尼亚洋流中急剧下降，国际沙丁鱼渔业正在崩溃，鲭鱼（Tr鱼（Trachurus symmetricus）和S蒲（Scomber japonicus））正在蓬勃发展。这种情况发生在1900年代中期，但是当前海洋状况的指数以及我们的声学拖网调查结果表明，这种情况现在很可能再次发生，可能会产生类似的社会经济和生态后果。同样令人震惊的是，渔业对沙丁鱼种群减少的反应的重复-针对最古老，最大和最肥沃的鱼类的利用率不断提高。此外，我们的数据表明，沙丁鱼最近的繁殖状况很差，其生产力低于用来推算当前渔业开发率的模型估计值。因此，沙丁鱼种群已减少到两个队列，不太可能产生可观的新队列。因此，取决于更温暖的海洋条件的恢复，鲭鱼物种压力的减轻以及可能采取更为预防性的策略来管理沙丁鱼残留的可能性，这种重要种群的近期恢复是不可能的。

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