| Summary: | This data set has trawl catch weight and biological measurements from the 2nd leg of the Icelandic part of the International Ecosystem Summer Survey in Nordic Seas (IESSNS) conducted in July 2020. The survey area was from the coast, over the shelf edge and into the deep-water basins south of Iceland and in the southern part of the Irminger Sea, defined as IESSNS strata 6, 11 and 12, see embedded map. The survey period was July 11 – 30, 2020, and samples were collected at 27 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 27 stations. Trawl depth ranged from surface (trawl headline in surface) to 550 m depth. 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 was extracted whole from the specimen at sea and read whole under a dissecting microscope on land by an experienced age reader which is a 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 2020). Various information is provided about the trawling operation and weather. The data is provided by the Marine and Freshwater Research Institute (MFRI) in Iceland.
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