Within recent years, a slight but significant increase of European eel Anguilla anguilla (L.) recruitment has been documented, but it remains questionable whether or not the increased recruitment levels resulted in higher eel numbers at the regional scale. To detect the changes in yellow eel numbers, logbook data covering a 15-year time series of catch per unit effort (CPUE) data from the German Baltic Sea were analysed. Monthly mean catch rates were calculated for two different size classes for two passive gears: fyke and stationary trap nets. Change-point analysis was applied to discover changes in the catch data. After a period of decreasing or constant catch rates, the fyke net data indicated that yellow eel numbers increased slightly in recent years in the Baltic Sea. Besides increasing numbers of immigrating juvenile eels, other population dynamics or conservation efforts might have added to the observed positive stock trend.

中文翻译：

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使用基于日志的捕获率数据检测波罗的海南部的黄鳗种群趋势

在最近几年，欧洲鳗的轻微但显著上升安圭拉 安圭拉(L.) 招募已被记录在案，但增加的招募水平是否导致区域范围内鳗鱼数量增加仍然值得怀疑。为了检测黄鳗数量的变化，分析了来自德国波罗的海的 15 年时间序列的单位努力捕获量 (CPUE) 数据的日志数据。每月平均捕获率是针对两种不同尺寸级别的两种被动渔具计算的：fyke 和固定捕集网。应用变化点分析来发现捕获数据的变化。经过一段时间的捕捞率下降或恒定，fyke net 数据表明，近年来波罗的海的黄鳗数量略有增加。除了越来越多的移民幼鳗外，其他种群动态或保护工作可能会增加观察到的积极种群趋势。