In contrast to the increasing aquaculture production of mussels worldwide, production in the European Union (EU) has shown a decreasing trend over the last two decades. Aquaculture production of mussels in the EU peaked in the late 1990s at more than 600 000 tonnes; by 2016, production volume had dropped by 20% to 480 000 tonnes. As mussel production represents more than ⅓ of EU aquaculture production, this decrease is an important contributor to the stagnation of EU aquaculture. Previous studies have suggested diseases, lack of mussel seed (spat), and low profitability as the main causes of the EU mussel production decrease. In this study, we investigate how economic and environmental factors have contributed. Moreover, we examine if the different mussel production techniques (raft, longline, on‐bottom, and ‘bouchot’) have been differently affected, by analysing the economic performance and cost structure evolution for the period 2010–2016. We complement these results with a SWOT (strengths, weaknesses, opportunities, and threats) analysis of the EU mussel sector based on expert knowledge.

中文翻译：

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欧盟贻贝养殖的下降：原因，经济影响和机遇

与世界范围内贻贝的水产养殖产量不断增长形成鲜明对比的是，过去二十年来，欧盟（EU）的产量呈下降趋势。欧盟贻贝的水产养殖产量在1990年代后期达到峰值，超过60万吨。到2016年，产量下降了20％，降至48万吨。由于贻贝产量占欧盟水产养殖产量的三分之二以上，因此这一下降是造成欧盟水产养殖停滞的重要原因。先前的研究表明，疾病，贻贝种子（种子）缺乏和盈利能力低是欧盟贻贝产量下降的主要原因。在这项研究中，我们调查了经济和环境因素的贡献。此外，我们还会检查贻贝的生产技术（筏，延绳钓，底下，通过分析2010-2016年期间的经济表现和成本结构演变，对“ bouchot”和“ bouchot”的影响不同。我们根据专家知识对欧盟贻贝行业进行SWOT分析（优势，劣势，机会和威胁），对这些结果进行补充。