Crangon crangon in the Sylt Rømø bight in 2020

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. 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.鉴于北海与瓦登海的温度动态发生改变，研究团队于2007年在叙特-勒姆湾（Sylt Rømø Bight，简称SRB）启动了一项鱼类调查项目，计划至少持续十年。本项目旨在调查瓦登海的鱼类区系，重点关注鱼类洄游行为、物种组成及摄食习性的变化。研究团队每月对SRB范围内的7个采样站位开展采样作业。另设2个参照站位：1个位于该海湾外侧，另1个毗邻丹麦边境，每年采样4次。本次调查采用总长17米的小型底拖网进行采样：拖网网口宽7米、高3米，网翼段网目尺寸为36毫米，中段为16毫米，囊网（cod end）网目尺寸为6毫米。每个站位均完成两次拖曳采样：一次在水体层中，一次在底质表面，单次拖曳时长15分钟，拖曳速度约为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格局。