National Oceanic and Atmospheric Administration, Alaska Fisheries Science Center, Kodiak, AK, 99615, USA.
Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, Port Orchard, WA, 98366, USA.
Sci Rep. 2021 Dec 14;11(1):23924. doi: 10.1038/s41598-021-03405-6.
Sustainability-maintaining catches within the historical range of socially and ecologically acceptable values-is key to fisheries success. Climate change may rapidly threaten sustainability, and recognizing these instances is important for effective climate adaptation. Here, we present one approach for evaluating changing sustainability under a changing climate. We use Bayesian regression models to compare fish population processes under historical climate norms and emerging anthropogenic extremes. To define anthropogenic extremes we use the Fraction of Attributable Risk (FAR), which estimates the proportion of risk for extreme ocean temperatures that can be attributed to human influence. We illustrate our approach with estimates of recruitment (production of young fish, a key determinant of sustainability) for two exploited fishes (Pacific cod Gadus macrocephalus and walleye pollock G. chalcogrammus) in a rapidly warming ecosystem, the Gulf of Alaska. We show that recruitment distributions for both species have shifted towards zero during anthropogenic climate extremes. Predictions based on the projected incidence of anthropogenic temperature extremes indicate that expected recruitment, and therefore fisheries sustainability, is markedly lower in the current climate than during recent decades. Using FAR to analyze changing population processes may help fisheries managers and stakeholders to recognize situations when historical sustainability expectations should be reevaluated.
在社会和生态可接受的范围内保持可持续性是渔业成功的关键。气候变化可能会迅速威胁到可持续性，因此认识到这些情况对于有效的气候适应至关重要。在这里，我们提出了一种评估气候变化下可持续性变化的方法。我们使用贝叶斯回归模型比较了历史气候规范和新兴人为极端条件下的鱼类种群过程。为了定义人为极端条件，我们使用归因风险分数（FAR），它估计了可以归因于人类影响的极端海洋温度风险的比例。我们用阿拉斯加湾快速变暖的生态系统中两种受捕捞鱼类（太平洋鳕鱼 Gadus macrocephalus 和大眼蓝鳕 G. chalcogrammus）的补充量（幼鱼的产量，可持续性的关键决定因素）的估计来说明我们的方法。我们表明，在人为气候极端条件下，这两个物种的补充分布都向零值转移。基于人为温度极端事件预计发生率的预测表明，与最近几十年相比，当前气候下的预期补充量（因此渔业可持续性）明显较低。使用 FAR 来分析变化的种群过程可能有助于渔业管理者和利益相关者认识到应该重新评估历史可持续性预期的情况。
