Adjusted barrier management to improve glass eel migration at an estuarine barrier
Adjusted barrier management to improve glass eel migration at an estuarine barrier
复制标题
调整屏障管理以改善玻璃鳗在河口屏障的迁移
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
J. Coeck
中科院分区：
文献类型：
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作者：
A. Mouton;M. Stevens;T. Neucker;D. Buysse;J. Coeck
欧洲鳗Anguilla Anguilla(L.)在过去的几十年里，种群数量急剧下降，现在是欧洲最濒危的鱼类种群之一。玻璃鳗上游迁徙的限制被认为是导致鳗鱼数量减少的关键因素之一。研究了鳗鱼幼体阶段(玻璃鳗鱼)的迁徙，并评估了在比利时佛兰德斯伊瑟河河口的潮汐屏障复合体改善鳗鱼通过的各种选择。在涨潮期间用张网和升降网采集玻璃鳗样本，分析其在研究区域的分布，同时使用Fyke网评估有限屏障开放对玻璃鳗迁徙的影响。基于支持向量机的提升网数据分析表明，从屏障渗漏的淡水吸引了正在迁徙的玻璃鳗，而采样位置等其他变量对玻璃鳗密度的影响很小。在涨潮期间有限度地开放屏障似乎是一种成本效益高和有效的缓解办法，可以在不明显侵入海水的情况下改善上游玻璃鳗的迁徙情况。调整后的屏障管理通常可以在许多潮汐屏障上实施和应用。因此，这篇论文的结果引起了广泛的河流管理者和利益相关者的兴趣，并可能有助于保护许多鳗鱼种群。
European eel Anguilla anguilla (L.) populations have declined dramatically during the last decades and are now among the most critically endangered fish populations in Europe. The limitation of upstream migration of glass eels is considered to be one of the key factors reducing eel populations. The migration of eels in their juvenile stage (glass eels) was studied, and options to improve eel passage at a tidal barrier complex at the mouth of the Yser River, Flanders, Belgium, were assessed. Glass eels were sampled during tidal rise with stow nets and lift nets to analyse their distribution over the study area, while a fyke net was used to evaluate the impact of limited barrier opening on glass eel migration. Support-vector machine-based analysis of the lift net data indicated that migrating glass eels are attracted by the fresh water flow leaking from the barriers, whereas other variables such as the sampling location only had a weak influence on the glass eel density. Limited barrier opening during tidal rise appeared to be a cost-efficient and effective mitigation option to improve upstream glass eel migration without significant intrusion of seawater. Adjusted barrier management could often be implemented and applied on numerous tidal barriers. Therefore the results of this paper are of interest to a wide range of river managers and stakeholders and may contribute to the conservation of many eel populations.