From 1 - 10 / 55
  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we studied the biomass of mesopelagic fish and its potential as a source of protein and oil for animal feed and human consumption. We collected samples of mesopelagic species down to a depth of 600?m, studied fish behaviour, identified and quantified the species composition of the catches, analysed the chemical composition of the catch samples, and evaluated the presence of unwanted substances. Results showed that Maurolicus muelleri (Mueller's pearlside) and Benthosema glaciale (Glacier lantern fish) were the most abundant fish species in our samples and catches containing 80% fish can be a good source of protein and marine lipids including eicosapentaenoic acid (C20:5n3) and docosahexaenoic acid (C22:6n3). Unwanted substances, except for Cd and As, were present at levels far lower than the limits set by European Union regulations. However, our experiments identified challenges that may limit the efficiency of commercial operations in the Northeast Atlantic. Combined real-time optical and/or multifrequency acoustic systems will be needed to improve species identification and ensure cost-effective fishing operations. Also, selective trawls that target only fish and release unwanted species are needed to secure high-quality oils and proteins.

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we collected samples of mesopelagic species down to a depth of 600?m and evaluated the presence of unwanted substances. Except for Cd and As, toxic compounds were present at levels far lower than the limits set by European Union regulations.

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we collected samples of mesopelagic species down to a depth of 600?m and analysed the chemical composition of the catch samples. We present gross proximate composition (g /100 g fresh weight) and fatty acid composition (% of total fatty acids) in mesopelagic raw material samples (values are mean ± standard deviation of 2–4 samples).

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we collected samples of mesopelagic species down to a depth of 600?m and analysed wax esters, triglycerides, free fatty acids, cholesterol and phospholipids (g/100 g oil) of four catch samples.

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we studied Maurolicus muelleri (Mueller's pearlside) wet mass, length, sex and maturity stages per size class.

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we studied the biomass of mesopelagic fish down to a depth of 600?m and identified and quantified the species composition of the catches. The biomass density was estimated considering the volume of water filtered by the cross-sectional area of the trawl blinded with 16 mm meshes (130 m–2), the distanced covered by the trawl (m) at a towing speed (transformed to m s–1) the effective tow time (min) and the catch (kg).

  • Categories  

    During three cruises in the Mid Atlantic Ridge area in 2016 and 2017, we collected samples of mesopelagic species down to a depth of 600?m. We studied fish behaviour and identified and quantified the species composition of the catches using HD videos (60 frames/s). For species identification and the estimation of the number of siphonophores/m³ we analysed the videos frame by frame using the tool VLC media player.

  • Categories  

    EK80 raw broadband stationary observations were made during the 2020 SUMMER (Sustainable Management of Mesopelagic Resources) Mediterranean cruise (30 September 2020 to 18 October 2020) aboard the RV Sarmiento de Gamboa. A hull-mounted EK80 system (with nominal frequencies of 18, 38, 70, 120, 200 kHz) was operated on frequency modulated (FM) mode with specific settings. In total, 22 deployments were collected along with the wideband autonomous transceiver (WBAT) observations to maximise the frequency band range and compare to the WBAT data. A maximum volume of 100 MB per individual raw file was used. The recording depth for 5 frequencies was set to 500 m. The transmitted power for 5 frequencies from 18 to 200 kHz were set to 2000, 1000, 750, 250, 150 W according to the published papers. Raw power (W), number of transducer segments and transceiver impedance (Ohm) were stored in raw proprietary Simrad format (.raw). The raw files were all recorded according to the UTC+00:00 time zone. Data format and calibrations are the same as for the EK80 underway narrowband data.

  • Categories  

    This data contains the logbook records from fishery vessels reporting pearlside, Maurolicus muelleri, from 2009 to 2011. The data contains all data registered in the logbook, from catch date to position, pearlside catch and by-catch by tow with pelagic trawls. Specifics of the trawls used (mostly modified capelin trawls) are indicated, e.g. circumference and mesh size. The location of the catches, the date of capture, the species IDs in the database of the Marine and Freshwater Research Institute of Iceland, the Latin, English and Icelandic names of species, and the tow time are recorded, too. Fishery vessel IDs are randomized due to data protection and are similar to the IDs mentioned in the associated biological data files for M. muelleri called “Biological data Maurolicus muelleri-Fisheries data and B3-2010 survey”. Associated biological information contains length distribution per trawl stations, trawl information, date, location, length, weight and age of the fish when available.

  • Categories