Distribution of mesopelagic fish in the Scotia Sea from RMT25 and pelagic trawls deployed from RRS James Clark Ross and RRS John Biscoe

Mesopelagic fish were sampled in the Scotia Sea using a 25 m2 opening and closing rectangular midwater trawl during five research cruises on RRS John Biscoe and RRS James Clark Ross. Nets sampled discrete layers, from the surface to 1000 m during austral spring, summer and autumn. The data include 17726 individual fish records from 66 taxa, the most abundant of which were myctophids of the genera Electrona, Gymnoscopelus, Krefftichthys and Protomyctophum and bathylagids (Bathylagus sp.). Length (standard length, total length or pre-anal fin length) was measured for the majority of specimens (16837), with sex and weight data also collected for many. The work was conducted as part of the BAS Ecosystems Programmes funded by the UK Natural Environment Research Council.