Department of Economics, University of Kiel, Wilhelm-Seelig-Platz 1, 24118, Kiel, Germany.
Kiel Insitute for the World Economy, Kiellinie 66, 24105 , Kiel, Germany.
Glob Chang Biol. 2016 Jan;22(1):264-70. doi: 10.1111/gcb.13060. Epub 2015 Sep 8.
Four marine fish species are among the most important on the world market: cod, salmon, tuna, and sea bass. While the supply of North American and European markets for two of these species - Atlantic salmon and European sea bass - mainly comes from fish farming, Atlantic cod and tunas are mainly caught from wild stocks. We address the question what will be the status of these wild stocks in the midterm future, in the year 2048, to be specific. Whereas the effects of climate change and ecological driving forces on fish stocks have already gained much attention, our prime interest is in studying the effects of changing economic drivers, as well as the impact of variable management effectiveness. Using a process-based ecological-economic multispecies optimization model, we assess the future stock status under different scenarios of change. We simulate (i) technological progress in fishing, (ii) increasing demand for fish, and (iii) increasing supply of farmed fish, as well as the interplay of these driving forces under different scenarios of (limited) fishery management effectiveness. We find that economic change has a substantial effect on fish populations. Increasing aquaculture production can dampen the fishing pressure on wild stocks, but this effect is likely to be overwhelmed by increasing demand and technological progress, both increasing fishing pressure. The only solution to avoid collapse of the majority of stocks is institutional change to improve management effectiveness significantly above the current state. We conclude that full recognition of economic drivers of change will be needed to successfully develop an integrated ecosystem management and to sustain the wild fish stocks until 2048 and beyond.
鳕鱼、三文鱼、金枪鱼和鲈鱼。虽然这两种鱼类——大西洋三文鱼和欧洲鲈鱼——的北美和欧洲市场供应主要来自水产养殖，但大西洋鳕鱼和金枪鱼主要来自野生种群。我们要解决的问题是，到 2048 年中期，这些野生种群的状况将会如何。虽然气候变化和生态驱动力对鱼类种群的影响已经引起了广泛关注，但我们主要关注的是研究不断变化的经济驱动力的影响，以及可变管理效果的影响。我们使用基于过程的生态经济多物种优化模型，评估在不同变化情景下的未来种群状况。我们模拟了（i）捕鱼技术的进步，（ii）鱼类需求的增加，以及（iii）养殖鱼类供应的增加，以及在不同（有限）渔业管理效果情景下这些驱动力的相互作用。我们发现经济变化对鱼类种群有重大影响。增加水产养殖产量可以减轻野生种群的捕捞压力，但这种效果可能会被不断增长的需求和技术进步所抵消，这两者都会增加捕捞压力。避免大多数种群崩溃的唯一解决方案是制度变革，将渔业管理效果显著提高到当前水平之上。我们的结论是，为了成功地发展综合生态系统管理并维持野生鱼类种群，直到 2048 年及以后，需要充分认识到变化的经济驱动力。
