10.15470/89uh0e https://ipt.gbif.es/resource?r=bottom_trawl_survey ICATMAR_bottom_trawl_survey Aram Puig Capdevila ICATMAR (CSIC-ICM) Desenvolupador Backend arampuig@icm.csic.es 0009-0006-7191-2869 Jordi Ribera Altimir ICATMAR (CSIC-ICM) jribera@icm.csic.es 0000-0002-8232-3334 2026-02-27 eng This dataset contains standardized abundance (individuals/km²) and biomass (kg/km²) data for marine demersal species collected through commercial bottom trawl surveys conducted by ICATMAR (Institut Català de Recerca per a la Governança del Mar) along the Catalan coast as part of the fisheries monitoring program. Fisheries monitoring Demersal fisheries Bottom trawling Mediterranean sea Catalan coast ICATMAR Information Systems GBIF Dataset Type Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_type_2015-07-10.xml Fisheries monitoring Demersal fisheries Bottom trawling Mediterranean sea Catalan coast ICATMAR Information Systems GBIF Dataset Subtype Vocabulary: http://rs.gbif.org/vocabulary/gbif/dataset_subtype.xml This work is licensed under a Creative Commons Attribution (CC-BY 4.0) License. Creative Commons Attribution 4.0 International https://spdx.org/licenses/CC-BY-4.0.html CC-BY-4.0 https://www.icatmar.cat/publicacions/ Surveys covered the major fishing ports along the Catalan coast in the North Western Mediterranean Sea (N GSA6). The sampling area extends from 40.32°N to 42.40°N latitude and 0.66°E to 3.62°E longitude. 0.662447 3.615714 42.395072 40.324136 2019-01-16 2024-12-18 This work was supported by the Catalan Institute for Ocean Governance Research (ICATMAR), rawl surveys were financed by European Maritime and Fisheries and Aquaculture Fund (EMFAF) and the agreement between the Spanish National Research Council (CSIC) and the Catalan Government (BOE-A-2023-251060). We are very thankful to all fishers for their support throughout the project. continually Aram Puig Capdevila ICATMAR (CSIC-ICM) Backend Developer arampuig@icm.csic.es http://icatmar.cat Jordi Ribera Altimir ICATMAR Head of Information Systems jribera@icm.csic.es 0000-0002-8232-3334 Adrià Martí Comas ICATMAR Backend Developer adria.marti@icm.csic.es 0009-0005-0266-0277 The fishers sort the catch into two categories: commercial, i.e., individuals of commercial species to be sold in the fish auction, and discarded, i.e., all other organic and inorganic organisms and items. The discarded fraction includes individuals of non-commercial species and/or undersized or damaged individuals of commercial species – as well as natural debris and marine litter. All species of the commercial fraction, including fish, crustaceans and cephalopods among others, are identified and measured on board (total length, cephalothorax length and mantle length, respectively) (Carreton M. et al. 2025). The study area comprises the entire Catalan coast, with 580 km of coastline, constitutes the northern half of the GSA 6, which in whole comprises from Cape Creus down to Cartagena (Resolution GFCM/33/2009/2). The spatial distribution of the fishing effort by port shows the local-scale structure of the Catalan bottom trawling sector: the fleet of each port fishes in waters directly off their port, and overlapping among influence areas of the different ports is low (around 10 % in fishing hours per km2, Mingote et al., in prep) and exists only among adjacent ports. We chose the 9 ports with the highest annual revenues which are also equidistant throughout the territory, attending to both hydrographic and geomorphological characteristics of the continental margin (shelf and slope). In the northernmost part of the Catalan coast, the continental shelf is cut by deep submarine canyons that allow for deep-sea fisheries activity while remaining relatively close to the coast. The coast between Arenys de Mar and Tarragona is characterized by the absence of submarine canyons and the influence of densely populated areas such as Barcelona, Vilanova i la Geltrú or Tarragona. The southernmost area of the coast is deeply affected by the discharge of the river Ebre, which generates a delta between L’Ampolla and La Ràpita. The division of the Catalan coast in these three zones responds to the morphometric mesoscale analysis of the margin and has been used in previous faunistic assemblage studies (Carreton M. et al. 2025). Sampling trips were carried out on board trawling fishing vessels, with no change to their usual fishing activity, over commercial fishing grounds. Each of the three sampling zones was sampled monthly, with a rotation among the three ports of each zone, resulting in one quarterly sampling at each of the 9 selected ports. This allowed for the monitoring of seasonal patterns throughout the year. Each sampling day included three experimental hauls on board the same vessel, each one at one of the three depth ranges previously explained, within the high-fishing effort areas of each port. Exceptionally, in 2019 and 2020, seven of the Southern zone hauls were conducted in the lower slope. The average depth for each haul was then estimated by calculating an average point between the start and end points of each haul. Mesh size was 40-mm square for all hauls except in Palamós lower slope, where the self-enforced local management measures for the blue and red shrimp fishery require a 50-mm squared mesh (BOE 2018, APM/532/2018). Each haul was GPS-recorded with a start and end point, fishing time and gear width. These measurements were used to calculate the total swept area per haul in order to standardize species biomass and abundance values. The sampling is designed to run a complete cycle throughout a calendar year so that the data are comparable annually, and the data analyzed in this study correspond to the years 2019–2021 (Carreton M. et al. 2025). All data collected go through a validation workflow to ensure high quality in their analysis and publishing. Using the data input website to ingest onboard and laboratory sampling data allows having more control of the data, prevents defects and facilitates validation, data availability and system reliability. This database includes parametrized text fields and the numeric fields with data ranges. Different validations are performed during the data input workflow to trigger warnings and detect errors to prevent defects. Finally, the data are displayed in interactive maps and charts to perform visual validations. The interactive maps use the library Leaflet and the interactive charts use the library Chartjs v2.8. At the end of each season, R scripts are executed to check joint data completeness and perform a general data validation (Ribera-Altimir J. et al. 2023). Jordi Ribera-Altimir 0000-0002-8232-3334 programmer Adrià Martí-Comas 0009-0005-0266-0277 programmer Aram Puig-Capdevila 0009-0006-7191-2869 programmer Ricardo Santos-Bethencourt 0000-0002-6821-8984 originator Alba Rojas 0000-0002-6234-3450 originator Marc Balcells 0000-0002-3512-7453 originator Adrià Olmo i Cerdà originator Alberto J. Rico 0000-0002-7835-8577 originator Alexis Rossell Vela 0009-0007-4152-298X contentProvider Antoni Lombarte 0000-0001-5215-4587 curator Begoña Martínez López 0009-0008-9471-0738 originator Cristina López-Pérez 0000-0002-8909-4060 originator Eve Galimany 0000-0003-1493-2944 principalInvestigator Ferran Bustos 0000-0001-5359-8518 originator Ivan Ruiz Perez originator Joan B. Company 0000-0002-5878-7155 principalInvestigator Joan Sala-Coromina 0000-0003-1221-7648 curator Julia Cao Sánchez 0009-0004-5824-3811 originator Laia Viure 0000-0002-7116-5609 contentProvider Laura Recasens 0000-0002-2821-1796 principalInvestigator Mariona Panisello-Garriga 0000-0002-1869-3074 curator Marta Blanco 0000-0002-8172-7628 curator Marta Carreton 0000-0002-9490-1453 curator Marta Nadal Pla originator Marta Pujol-Baucells 0000-0002-4946-3386 curator Mireia G. Mingote 0009-0008-8732-6092 curator Mireia Silvestre 0000-0001-7120-4543 originator Pablo Couve 0000-0002-8464-3825 curator Patrícia Poch i Isern 0009-0002-7302-3388 originator Xènia Puigcerver-Segarra 0000-0002-2212-5643 originator The Directorate-General for Maritime Policy and Sustainable Fisheries of the Catalan Government and the Institut de Ciències del Mar (ICM-CSIC) promoted the Institut Català de Recerca per a la Governança del Mar (ICATMAR), an autonomous organization whose main goal is to generate scientific advice to regional, state and European administrations for management purposes. Since 2019, ICATMAR has developed and implemented a fisheries monitoring program that aims to complement the data collection protocol already in place, working at a local scale to gather information on spatial and seasonal variability of the factors that can shape fishing stocks dynamics. Trawl surveys were financed by European Maritime and Fisheries and Aquaculture Fund (EMFAF) and the agreement between the Spanish National Research Council (CSIC) and the Catalan Government (BOE-A-2023-251060). The study area comprises the entire Catalan coast, with 580 km of coastline, constitutes the northern half of the GSA 6, which in whole comprises from Cape Creus down to Cartagena (Resolution GFCM/33/2009/2). The spatial distribution of the fishing effort by port shows the local-scale structure of the Catalan bottom trawling sector: the fleet of each port fishes in waters directly off their port, and overlapping among influence areas of the different ports is low (around 10 % in fishing hours per km2, Mingote et al., in prep) and exists only among adjacent ports. We chose the 9 ports with the highest annual revenues which are also equidistant throughout the territory, attending to both hydrographic and geomorphological characteristics of the continental margin (shelf and slope). In the northernmost part of the Catalan coast, the continental shelf is cut by deep submarine canyons that allow for deep-sea fisheries activity while remaining relatively close to the coast. The coast between Arenys de Mar and Tarragona is characterized by the absence of submarine canyons and the influence of densely populated areas such as Barcelona, Vilanova i la Geltrú or Tarragona. The southernmost area of the coast is deeply affected by the discharge of the river Ebre, which generates a delta between L’Ampolla and La Ràpita. The division of the Catalan coast in these three zones responds to the morphometric mesoscale analysis of the margin and has been used in previous faunistic assemblage studies (Carreton M. et al. 2025). Sampling trips were carried out on board trawling fishing vessels, with no change to their usual fishing activity, over commercial fishing grounds. Each of the three sampling zones was sampled monthly, with a rotation among the three ports of each zone, resulting in one quarterly sampling at each of the 9 selected ports. This allowed for the monitoring of seasonal patterns throughout the year. Each sampling day included three experimental hauls on board the same vessel, each one at one of the three depth ranges previously explained, within the high-fishing effort areas of each port. Exceptionally, in 2019 and 2020, seven of the Southern zone hauls were conducted in the lower slope. The average depth for each haul was then estimated by calculating an average point between the start and end points of each haul. Mesh size was 40-mm square for all hauls except in Palamós lower slope, where the self-enforced local management measures for the blue and red shrimp fishery require a 50-mm squared mesh (BOE 2018, APM/532/2018). Each haul was GPS-recorded with a start and end point, fishing time and gear width. These measurements were used to calculate the total swept area per haul in order to standardize species biomass and abundance values. The sampling is designed to run a complete cycle throughout a calendar year so that the data are comparable annually, and the data analyzed in this study correspond to the years 2019–2021 (Carreton M. et al. 2025). 2026-01-26T17:41:58.123+01:00 dataset Ribera-Altimir, J., Martí-Comas, A., Puig-Capdevila, A., Santos-Bethencourt, R., Rojas-Garcia, A., Balcells-Surroca, M. (2026). ICATMAR bottom trawl survey data in the NW Mediterranean (commercial and bycatch species). www.icatmar.cat Carreton, M., Galimany, E., Blanco, M., Garriga-Panisello, M., Colmenero, A. I., Balcells, M., Bustos, F., Mingote, M. G., López-Pérez, C., Nos, D., Puigcerver-Segarra, X., Pujol-Baucells, M., Ramírez, J. G., Ribera-Altimir, J., Rico, A. J., Rojas, A., Sala-Coromina, J., Santos-Bethencourt, R., Silvestre, M., … Company, J. B. (2025). Understanding the spatio-temporal variability of fisheries data for better bottom trawling management practices in the Catalan margin (NW Mediterranean Sea). Marine Policy, 172, 106512. Ribera-Altimir, J., Llorach-Tó, G., Sala-Coromina, J., B. Company, J., & Galimany, E. (2023). Fisheries data management systems in the NW Mediterranean: from data collection to web visualization. Database, 2023. Blanco, M., Nos, D., Lombarte, A., Recasens, L., Company, J. B., & Galimany, E. (2023). Characterization of discards along a wide bathymetric range from a trawl fishery in the NW Mediterranean. Fisheries Research, 258, 106552. https://ipt.gbif.es/resource?id=bottom_trawl_survey/v2.xml