Clarke Shelley C, McAllister Murdoch K, Milner-Gulland E J, Kirkwood G P, Michielsens Catherine G J, Agnew David J, Pikitch Ellen K, Nakano Hideki, Shivji Mahmood S
Joint Institute for Marine and Atmospheric Research, University of Hawaii and National Research Institute of Far Seas Fisheries, 5-7-1 Shimizu-Orido, Shizuoka 424-8633, Japan.
Ecol Lett. 2006 Oct;9(10):1115-26. doi: 10.1111/j.1461-0248.2006.00968.x.
Despite growing concerns about overexploitation of sharks, lack of accurate, species-specific harvest data often hampers quantitative stock assessment. In such cases, trade studies can provide insights into exploitation unavailable from traditional monitoring. We applied Bayesian statistical methods to trade data in combination with genetic identification to estimate by species, the annual number of globally traded shark fins, the most commercially valuable product from a group of species often unrecorded in harvest statistics. Our results provide the first fishery-independent estimate of the scale of shark catches worldwide and indicate that shark biomass in the fin trade is three to four times higher than shark catch figures reported in the only global data base. Comparison of our estimates to approximated stock assessment reference points for one of the most commonly traded species, blue shark, suggests that current trade volumes in numbers of sharks are close to or possibly exceeding the maximum sustainable yield levels.
尽管人们越来越担心鲨鱼被过度捕捞，但缺乏准确的、按物种分类的捕捞数据常常阻碍定量种群评估。在这种情况下，贸易研究可以提供传统监测无法获得的有关捕捞情况的见解。我们将贝叶斯统计方法应用于贸易数据，并结合基因识别技术，按物种估计全球每年交易的鲨鱼鳍数量，鲨鱼鳍是一组通常未记录在捕捞统计数据中的物种中最具商业价值的产品。我们的结果首次提供了与渔业无关的全球鲨鱼捕捞规模估计，并表明鱼翅贸易中的鲨鱼生物量比唯一的全球数据库中报告的鲨鱼捕捞量高三到四倍。将我们的估计值与最常交易的物种之一蓝鲨的近似种群评估参考点进行比较，结果表明，目前鲨鱼数量的交易量接近或可能超过最大可持续产量水平。
