Osmerus eperlanus in the Sylt Rømø bight in 2022

Due to changing temperature regimes in the North- and the Wadden Sea, a fish survey in the Sylt Rømø bight (SRB) was established in 2007 for at least ten years. The aim is to investigate the Wadden Sea fish fauna with special interest in changes of migration behavior, species composition and feeding habits. Since 2021 an assessment of the epibenthic species in the net hauls was included. Seven stations are sampled monthly inside the SRB. Two additional stations, one outside the bight, one close to the Danish border are sampled as references four times a year. For sampling a mini bottom trawl, total length 17 m, trawl opening 7 m, height 3 m with a mesh size of 36 mm in the wings, 16 mm in the mid part and 6 mm in the cod end is used. At every station one haul in the water column and another at the bottom are sampled, for 15 minutes at a speed of approximately 2 knots. The data will help to give a more detailed picture of food chains and energy flows inside the Wadden Sea.

鉴于北海与瓦登海（Wadden Sea）的温度格局发生变化，研究团队于2007年在叙尔特-勒姆湾（Sylt Rømø Bight，简称SRB）设立鱼类调查项目，原计划至少持续十年。本项目旨在调查瓦登海的鱼类区系，重点关注其洄游行为、物种组成与摄食习性的变化。自2021年起，项目新增了对网获样本中的底上生物（epibenthic species）的评估环节。叙尔特-勒姆湾内共设7个采样站位，每月开展一次采样；另增设2个对照站位，分别位于湾外及邻近丹麦边境区域，每年采样4次。采样采用小型底拖网，总长度17米，网口跨度7米、高度3米；网翼网目尺寸为36毫米，中部网目16毫米，囊网网目6毫米。每个站位分别开展一次水层拖网与一次底拖网采样，拖曳时长均为15分钟，拖曳速度约2节。本项目所获数据将有助于更细致地刻画瓦登海内部的食物链与能量流动机制。