Fish and invertebrate trawl sampling south and west of Iceland in July 2022@en

This data set has trawl catch weight and biological measurements from the latter half of the Icelandic part of the International Ecosystem Summer Survey in Nordic Seas (IESSNS) conducted in July 2022. The survey area was from the coast and over the shelf edge south and west of Iceland, defined as IESSNS strata 5 and 6, see embedded map. The survey period was July 13 – 21, 2022, and samples were collected at 34 trawl stations. A specifically designed scientific trawl, called Multpelt832 (ICES, 2013a-b, Valdemarsen et al., 2014) with cod-end mesh size of 50+ mm, was used at all 34 stations. Trawl depth ranged from surface (trawl headline in surface) at 32 stations and 2 stations was trawling deeper in the water column targeting specific acoustic backscatter with trawl depth of 270 – 350 m. All trawl catch was identified to lowest possible taxonomic level, total weight of each species recorded, and length and weight of 50 specimen per species measured, or all if less was caught. For blue whiting (Micromesistius poutassou), herring (Clupea harengus), and mackerel (Scomber scombrus) more biological measurements are provided such as sex, maturity, age, and stomach weight. For age determination, the otolith or scale was extracted whole from specimen at sea and read whole under a dissecting microscope on land by an experienced age reader part of the ICES framework. Gonad maturity stage was visually estimated at sea during sampling by an experienced technician. For taxa Scyphozoa and Natantia decapods only total catch weight per station is recorded. For detailed information about the survey see the survey report (Ólafsdóttir and Kennedy, 2022), in Icelandic and abstract, figure and table headings also provided in English. Various information about the trawling operation and weather is included in the file. The data is provided by the Marine and Freshwater Research Institute in Iceland.本数据集包含2022年7月开展的北欧海国际生态系统夏季调查（International Ecosystem Summer Survey in Nordic Seas，缩写IESSNS）冰岛海域后半段的拖网捕捞重量与生物学测量数据。本次调查的作业区域为冰岛以南及以西的近岸至陆架边缘海域，对应IESSNS第5、6分层（详见内嵌地图），调查时段为2022年7月13日至21日，共在34个拖网站位采集样品。 所有34个站位均使用专为科研设计的Multpelt832型科学拖网（ICES, 2013a-b, Valdemarsen et al., 2014），其囊网网目尺寸为50+毫米。拖网作业水深情况如下：32个站位采用表层拖网（拖网上纲处于表层水域），剩余2个站位在水层中开展深层拖网作业，目标为特定声学散射信号，作业水深范围为270–350米。 所有拖网捕获生物均被鉴定至尽可能低的分类学阶元，记录各物种的总重量，并针对每个物种测量50个标本的体长与体重；若单物种捕获量不足50个，则测量全部个体。针对蓝鳕（Micromesistius poutassou）、大西洋鲱（Clupea harengus）和大西洋鲭（Scomber scombrus），本数据集还提供了更多生物学测量指标，包括性别、成熟度、年龄以及胃重。 年龄鉴定所用的耳石或鳞片均在海上从标本中完整取出，随后由隶属于国际海洋考察理事会（ICES）框架的资深年龄读片人员在陆地实体显微镜下完成读片。性腺成熟度则由经验丰富的技术人员在海上采样过程中通过目视评估确定。对于钵水母纲（Scyphozoa）和十足目游泳亚目（Natantia decapods），仅记录每个站位的总捕捞重量。 有关本次调查的详细信息，请参阅调查报告（Ólafsdóttir and Kennedy, 2022），该报告以冰岛语撰写，附带英文摘要、图表及表格标题。数据集文件中还包含拖网作业及气象相关的各类辅助信息。本数据集由冰岛海洋与淡水研究所提供。