This dataset includes 3D sagittal left otolith meshes obtained from 339 individual red mullet (Mullus barbatus) specimens. These samples were collected from 17 distinct geographical locations spanning the whole Mediterranean Sea. Recorded biological parameters include fish total length (TL, ranging from 125 to 238 mm), total weight (W, ranging from 14.9 to 168.0 g), sex, and sexual maturity staging. The 3D otolith dataset consists of high-resolution meshes obtained through microtomography (29.2 m voxel size). The dataset provides valuable insights into the morphological variability and population structure of red mullet populations in the Mediterranean Sea. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

Since its establishment in 2010, the Mayotte Marine Natural Park has been promoting fishing activities beyond the lagoon, specifically targeting pelagic species to alleviate fishing pressure on reef species. However, despite these efforts, catches of reef fish remain notably high. In 2020, reef carnivores (groupers, snappers…), constituted approximately 35% of the total catches. Ensuring the sustainability of reef fishing necessitates regular assessments of Mayotte's commercial reef fish populations. This study aims to evaluate the current status of these populations and comprehend their dynamics by comparing them with historical data. Scuba diving was employed for the assessment of ichthyological populations and habitat description. In 2023, a total of 96 sites, comprising 1,100 stations (Stationary visual census), were sampled, covering a combined sampled area of 169,400 m2, with an in situ observation duration totalling 110 hours. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

This dataset includes all the CHALIST surveys between 1983 and 1992, that is five surveys undertaken in 1983, 1985, 1986, 1987 and 1992. The aim of CHALIST surveys was to evalute the demersal resources of the Gulf of Lion in order to monitor annual variations of the main commercial species in terme of spatial distribution, average weight and size and age compositions and abundance indices. All the target species collected were identified, weighted and counted. Length measurements were also carried out for a number of species. Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

This dataset shows spawning and nursery grounds of commercially important species: Horse Mackerel.

Data were collected in the Southwest Greenland Fjords for the Eurofleets+ GSHARK cruise with the R/V Dana. This submission contains all CTD data and the shark observations. The team tried to use the CTD in several stations but it was not functioning properly so only 1 vertical profile was gathered (on 02/08/2021 near station 3, 60,6958 -46,0373).

The ClimateFish database collates abundance data of 15 fish species proposed as candidate indicators of climate change in the Mediterranean Sea. An initial group of eight Mediterranean indigenous species (Epinephelus marginatus, Thalassoma pavo, Sparisoma cretense, Coris julis, Sarpa salpa, Serranus scriba, Serranus cabrilla and Caranx crysos) with wide distribution, responsiveness to temperature conditions and easy identification were selected by a network of Mediterranean scientists joined under the CIESM programme ‘Tropical Signals’ (https://www.ciesm.org/marine/programs/tropicalization.htm; Azzurro et al. 2010). Soon after, and thanks to the discussion with other expert groups and projects, C. crysos was no longer considered, and Lessepsian fishes (Red Sea species entering the Mediterranean through the Suez Canal) were included, namely: Fistularia commersonii, Siganus luridus, Siganus rivulatus, Pterois miles, Stephanolopis diaspros, Parupeneus forskali, Pempheris rhomboidea and Torquigener flavimaculosus. Considering the trend of increase of these species in the Mediterranean Sea (Golani et al. 2021) and their projected distribution according to climate change scenarios (D’Amen and Azzurro, 2020), more data on these tropical invaders are expected to come in the future implementation of the study. Data were collected according to a simplified visual census methodology (Garrabou et al. 2019) along standard transects of five minutes performed at a constant speed of 10m/min, corresponding approximately to an area of 50x5m. Four different depth layers were surveyed:  0-3m, 5-10 m, 11-20 m, 21-30 m. So far, the ClimateFish database includes fish counts collected along 3142 transects carried out in seven Mediterranean countries between 2009 and 2021, for a total number of 101'771 observed individuals belonging to the 15 fish species. Data were collected by a large team of researchers which joined in a common monitoring strategy supported by different international projects, which are acknowledged below. This database, when associated with climate data, offers new opportunities to investigate spatio-temporal effects of climate change in the Mediterranean Sea and test the effectiveness of each species as a possible climate change indicator.   Contacts: ernesto.azzurro(at)cnr.it   References: Azzurro E., Maynou F., Moschella P. (2010). A simplified visual census methodology to detect variability trends of coastal mediterranean fishes under climate change scenarios. Rapp. Comm. int. Mer Médit., 39. D’Amen, M. and Azzurro, E. (2020). Lessepsian fish invasion in Mediterranean marine protected areas: a risk assessment under climate change scenarios. ICES Journal of Marine Science, 77(1), pp.388-397. Garrabou, J., Bensoussan, N., Azzurro, E. (2019). Monitoring climate-related responses in Mediterranean marine protected areas and beyond: five standard protocols. Golani D.,  Azzurro E.,  Dulcic J.,  Massutí E., Orsi-Relini L.  (2021).  Atlas of Exotic Fishes in the Mediterranean Sea.  2nd edition  [F. Briand, Ed.]  365 pages.  CIESM Publishers, Paris, Monaco. ISBN number  978-92-990003-5-9    Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

The RV Arni Fredriksson collected simultaneous information on hydrology, prey and Brunnichs/common guillemot from 18 to 25/06/2022 in north-west Iceland. 5 transects of 60km length were succesfully completed twice in shelf-waters. A 6th transect of ~ 40km length was performed once in Arnarfjordur. During transects, 2 observers recorded the 2D distribution of all seabirds using European Seabird At-Sea (ESAS) methodology. At the same time, a scientific echosounder (Simrad EK80) operating at 5 frequencies (18, 38, 70, 120, 200 Khz) recorded the 3D distribution of fish. 22 trawls (plankton, midwater and demersal) were performed in response to schools and layers detected in the scientific echosounder, offering insights into their species composition and length-frequencies. 107 CTDs were performed at intervals along transects to measure the 3D variation in temperature, salinity, flourescene and turbidity.

This dataset gathers data used to determine seasonal and ontogenic variation of whiting (Merlangius merlangus) diet in the Eastern English Channel and south of the North Sea : (1) Individual C and N isotopic ratios, length and mass, for all individuals considered (2) Individual stomach content data. In the stomach content database, each individual is represented by several lines, each line representing one prey type Important Note: This submission has been initially submitted to SEA scieNtific Open data Edition (SEANOE) publication service and received the recorded DOI. The metadata elements have been further processed (refined) in EMODnet Ingestion Service in order to conform with the Data Submission Service specifications.

Species abundance and seagrass cover. Calculated from photo quadrats and video recorded by divers along seabed transects surveyed by divers as part of GENIALG monitoring surveys. Seaweed farm located in Ventry Harbour, Co. Kerry (Ireland). The samples were collected at seven different time points along the growing season in 2018 and 2019. Samples collected as part of the GENIALG project (project ID: 727892, GENIALG - GENetic diversity exploitation for Innovative Macro-ALGal biorefinery, http://genialgproject.eu/). GENIALG was funded by the European Union Horizon2020 programme. The remit of the work was assessing the environmental footprint and ecosystem services provided by seaweed aquaculture in Europe to provide best practice advice to industry.

This dataset shows nursery grounds of commercially important species, Atlantic Hake.