Spatially explicit estimates of length and biomass of Micromesistius poutassou (Blue Whiting) from acoustic and trawl surveys in the North-East Atlantic in May 2011

• Main Author: Huse, Geir
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2014
• Subjects: Event label; LATITUDE; LONGITUDE; DATE/TIME; Code; Area; Micromesistius poutassou abundance as Nautical Area Scattering Coefficient; Micromesistius poutassou, biomass; after MacLennan et al. 2002; Calculated from nautical area scattering coefficient; Basin Scale Analysis, Synthesis and Integration EURO-BASIN; Foote; North East Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.827379; https://doi.pangaea.de/10.1594/PANGAEA.827379

Acoustic estimates of herring and blue whiting abundance were obtained during the surveys using the Simrad ER60 scientific echosounder. The allocation of NASC-values to herring, blue whiting and other acoustic targets were based on the composition of the trawl catches and the appearance of echo recordings. To estimate the abundance, the allocated NASC -values were averaged for ICES-squares (0.5° latitude by 1° longitude). For each statistical square, the unit area density of fish (rA) in number per square nautical mile (N*nm-2) was calculated using standard equations (Foote et al., 1987; Toresen et al., 1998). To estimate the total abundance of fish, the unit area abundance for each statistical square was multiplied by the number of square nautical miles in each statistical square and then summed for all the statistical squares within defined subareas and over the total area. Biomass estimation was calculated by multiplying abundance in numbers by the average weight of the fish in each statistical square then summing all squares within defined subareas and over the total area. The Norwegian BEAM soft-ware (Totland and Godø 2001) was used to make estimates of total biomass. : The research leading to these results received (partial/full) funding from the European Commission FP7 EURO-BASIN (European Basin-Scale Anal ysis, Synthesis, and Integration; Grant Agreement 264 933).