HERAS - 0813S - Herring acoustic survey 2013 - North Sea and west of Scotland - Scotia dataset https://portal.medin.org.uk/portal/start.php?tpc=012_Marine_Scotland_FishDAC_1707 Daily folders (17) of Simrad format (.raw) acoustic data. 17 Echoview format (EV) format analysis files. Excel biological data for 28 pelagic hauls. CTD data for 39 vertical dips. Excel data for 41 plankton dips. 16 dips for mackerel egg sampling. Continual thermosalinograph data. continual AGDS data.Objectives. To conduct an acoustic survey to estimate the abundance and distribution of herring in the north western North Sea and north of Scotland between 58º30’-62ºN and from the shelf edge to 2ºE, excluding Faroese waters. To obtain biological samples for echosounder trace identification using a pelagic trawl.To obtain samples of herring for biological analysis, including age, length, weight, sex, maturity and ichthyophonus infection.To obtain dry weight estimates of macro zooplankton biomass throughout the study area for comparison with acoustically derived plankton biomass estimates and observed herring distribution.To identify mackerel eggs from ancillary plankton samples collected in the Western area of the survey. 20160329