Center for Limnology, University of Wisconsin-Madison, Madison, WI 53706;
Fisheries and Aquaculture Department, Food and Agriculture Organization of the United Nations, 00153 Rome, Italy.
Proc Natl Acad Sci U S A. 2018 Jul 17;115(29):7623-7628. doi: 10.1073/pnas.1721097115. Epub 2018 Jun 18.
Consumption of wild-caught freshwater fish is concentrated in low-income countries, where it makes a critical contribution to food security and livelihoods. Underestimation of inland harvests in official statistics has long been suspected due to unmonitored subsistence fisheries. To overcome the lack of data from extensive small-scale harvests, we used household consumption surveys to estimate freshwater fish catches in 42 low- and middle-income countries between 1997 and 2014. After accounting for trade and aquaculture, these countries collectively consumed 3.6 MT (CI, 1.5-5.8) more wild-caught freshwater fish than officially reported, reflecting a net underreporting of 64.8% (CI, 27.1-103.9%). Individual countries were more likely to underestimate ( = 31) than overestimate ( = 11) catches, despite conservative assumptions in our calculations. Extrapolating our findings suggests that the global inland catch reported as 10.3 MT in 2008 was more likely 16.6 MT (CI, 2.3-30.9), which accords with recent independent predictions for rivers and lakes. In human terms, these hidden harvests are equivalent to the total animal protein consumption of 36.9 (CI, 30.8-43.4) million people, including many who rely upon wild fish to achieve even minimal protein intake. The widespread underreporting uncovered by household consumption surveys indicates that inland fisheries contribute far more to global food security than has been recognized previously. Our findings also amplify concerns about the sustainability of intensive fishery exploitation as degradation of rivers, lakes, and wetlands continues apace.
野生淡水鱼的消费主要集中在低收入国家，对这些国家的粮食安全和生计至关重要。由于未监测到以生存为目的的小规模渔业，官方统计数据长期以来一直怀疑内陆捕捞量被低估。为了克服对广泛小规模捕捞缺乏数据的问题，我们利用家庭消费调查来估计 1997 年至 2014 年间 42 个低收入和中等收入国家的淡水鱼捕捞量。在考虑到贸易和水产养殖之后，这些国家共消费了 360 万吨（置信区间，1.5-5.8）野生捕捞淡水鱼，比官方报告的多出 64.8%（置信区间，27.1-103.9%）。尽管我们的计算存在保守假设，但个别国家更有可能低估（=31）而不是高估（=11）捕捞量。我们的研究结果表明，2008 年报告的全球内陆捕捞量为 1030 万吨，更有可能为 1660 万吨（置信区间，230 万吨至 3090 万吨），这与最近对河流和湖泊的独立预测相符。从人类的角度来看，这些隐藏的捕捞量相当于 3690 万人（置信区间，3080 万人至 4340 万人）的动物蛋白总消费量，其中包括许多依靠野生鱼类来实现最低蛋白质摄入量的人。家庭消费调查揭示的广泛低估表明，内陆渔业对全球粮食安全的贡献远远超过以前的认识。我们的研究结果还加剧了人们对密集渔业开发可持续性的担忧，因为河流、湖泊和湿地的退化仍在继续。
