Frequency and intensity of productivity regime shifts in marine fish stocks
Frequency and intensity of productivity regime shifts in marine fish stocks
复制标题
海洋鱼类种群生产力状况转变的频率和强度
DOI：
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复制
发表时间：
2013
影响因子：
11.1
通讯作者：
R. Hilborn
中科院分区：
文献类型：
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作者：
Katyana A. Vert;R. Amoroso;O. Jensen;R. Hilborn
鱼类种群的丰度和生产力（净种群增长）都会波动，并且有许多例子表明，生产力的增加或减少是由于捕捞引起的丰度变化，或者生产力在低和高状态之间变化，与丰度完全无关。尽管已经描述了生产力制度的转变，但之前尚未评估其频率和强度。我们使用 230 个鱼类种群的收获和丰度趋势数据库来评估生产力主要与丰度相关的鱼类种群与那些表现出高或低生产力状况的鱼类种群的比例。我们评估了四个假设的统计支持：（i）丰度假设，其中产量始终与人口丰度相关； (ii) 制度假说，即生产在与丰度无关的制度之间不规则地转移； (iii) 混合假设，即尽管产量与人口丰度相关，但这种关系存在不规则变化； (iv) 随机假设，其中产量每年都是随机的。我们发现，丰度假说最好地解释了 18.3% 的股票，制度假说解释了 38.6%，混合假说解释了 30.5%，随机假说解释了 12.6%。渔业管理机构需要认识到，生产力的不规则变化是常见的，并且每当生产力变化时，可能需要调整捕捞监管和管理目标。
Fish stocks fluctuate both in abundance and productivity (net population increase), and there are many examples demonstrating that productivity increased or decreased due to changes in abundance caused by fishing and, alternatively, where productivity shifted between low and high regimes, entirely unrelated to abundance. Although shifts in productivity regimes have been described, their frequency and intensity have not previously been assessed. We use a database of trends in harvest and abundance of 230 fish stocks to evaluate the proportion of fish stocks in which productivity is primarily related to abundance vs. those that appear to manifest regimes of high or low productivity. We evaluated the statistical support for four hypotheses: (i) the abundance hypothesis, where production is always related to population abundance; (ii) the regimes hypothesis, where production shifts irregularly between regimes that are unrelated to abundance; (iii) the mixed hypothesis, where even though production is related to population abundance, there are irregular changes in this relationship; and (iv) the random hypothesis, where production is random from year to year. We found that the abundance hypothesis best explains 18.3% of stocks, the regimes hypothesis 38.6%, the mixed hypothesis 30.5%, and the random hypothesis 12.6%. Fisheries management agencies need to recognize that irregular changes in productivity are common and that harvest regulation and management targets may need to be adjusted whenever productivity changes.