Impact of the invasive three-spined stickleback (Gasterosteus aculeatus) on relative abundance and growth of native pelagic whitefish (Coregonus wartmanni) in Upper Lake Constance
Impact of the invasive three-spined stickleback (Gasterosteus aculeatus) on relative abundance and growth of native pelagic whitefish (Coregonus wartmanni) in Upper Lake Constance
复制标题
入侵的三刺刺鱼（Gasterosteus aculeatus）对博登湖上游本地中上层白鲑（Coregonus wartmanni）的相对丰度和生长的影响
作者：
R. Rösch;J. Baer;A. Brinker
自2013年以来，康斯坦斯湖上游（ULC）的远洋区受到非本地三棘棘鱼（Gasterosteus aculeatus Linnaeus, 1758）的大规模入侵。利用每月监测远洋白鱼（Coregonus wartmanni Bloch, 1784）的数据，比较了入侵前（1997-2012年）和入侵后（2013-2015年）多年的体重-年龄和远洋白鱼丰度。研究表明，棘鱼的存在严重影响了远洋白鱼的生长和数量。入侵发生后，白鱼的平均秋龄体重下降了33.3%，未捕捞群体的秋龄体重也显著下降。结果表明，棘鱼的存在对远洋白鱼有直接影响，包括种间食物竞争导致生长和生存减少，以及捕食卵和幼虫，阻碍了招募。这些观察结果与白鱼产量急剧下降相吻合。综上所述，本研究表明，刺鱼的入侵极大地改变了ULC的中上层鱼类群落，对商业渔业造成了严重后果。
Since 2013, the pelagic zone of Upper Lake Constance (ULC) has been subject to a massive invasion of the non-native three-spined stickleback (Gasterosteus aculeatus Linnaeus, 1758). Data from monthly monitoring of pelagic whitefish (Coregonus wartmanni Bloch, 1784) were used to compare weight-at-age and abundance of pelagic whitefish for years before (1997–2012) and after the invasion (2013–2015). Growth and abundance of pelagic whitefish is shown to be heavily influenced by stickleback presence. Mean autumn weight-at-age of whitefish decreased by 33.3% after the invasion took place and a significant decline in autumn CPUE in otherwise unfished cohorts of the population was also recorded. The results imply direct effects of stickleback presence on pelagic whitefish, including interspecific competition for food leading to reduced growth and survival, and predation of eggs and larvae, hampering recruitment. These observations coincide with a sharp decline in whitefish yield. In conclusion, this study shows that the invasion of stickleback has substantially altered the pelagic fish community of ULC, with severe consequences for commercial fisheries.