On an established methodological basis, using the MEDITS protocol, half-hour bottom trawls are carried out using a standard scientific trawl used since 1994 on all European bottom trawl surveys (Spedicato et al., 2019). It was implemented in accordance with the recommendations described in the MEDITS handbook (MEDITS WG, 2017) using a reduced mesh size (20mm stretched) in the cod-end allowing for the capture of juveniles. Representative sub-samples of the catches were brought back to the laboratory to allow sorting, identification, counting (except for colonial invertebrates) and weighing of all the species captured and to carry out individual biological monitoring for some of them (size, weight, sexual maturity) using the sampling strategy, tools and methodologies detailed in Vaz et al. 2023a.

The data is in the ELevated FIsh Catch (ELFIC) format, were all sub-sample observations were elevated to the level of the total catch in the catch table. It is also strongly recommended to standardise catch values per km² or per hour as haul duration, gear geometry and swept area may vary from one observation to the next.

We also recommend this dataset to be analysed in conjunction with the MEDITS 2022 data to complete it with spring and summer 2022 observations.

The present dataset is composed of a pdf document describing the structure and content of each file, and 5 csv files containing the metadata and data.