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). The survey area was from the coast, over the shelf edge and into the deep-water basins south and west of Iceland, defined as IESSNS strata 5, 6, and 12, and stratum boundaries (black solid line) are displayed on attached map "IESSNS 2018.png". The survey period is July 19th to August 1st, 2018, and samples were collected at 34 trawl stations (blue symbol on attached map "IESSNS 2018.png"). 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) to 400 m depth. All trawl catch is identified to lowest possible taxonomic level, total weight of each species recorded and length of 20-50 specimen per species measured. For blue whiting (Micromesistius poutassou), herring (Clupea harengus), and mackerel (Scomber scombrus) more biological measurements are provided such as weight, sex, maturity, age, liver weight and stomach weight. Each specimen is one row in the data set file. Natantia and Scyphozoa specimen could not be identified to species, hence no individual length measurements are provided but total weight of catch per taxon is provided. For detailed information about the survey see the survey report (Ólafsdóttir and Jónsson 2019). Various information is provided about the trawling operation, weather, position, date and time.
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