3770386de4ddb72452f718b1bf4732c5 English dataset Data Archive for Marine Species and Habitats (DASSH) Data Archive for Marine Species and Habitats 01752426237 dassh.enquiries@mba.ac.uk pointOfContact 2025-05-27 MEDIN 3.1.2 EPSG Geodetic Parameter Registry 2021-01-06 revision WGS 84 2017-2018 Benthic bycatch from dredge surveys for seed mussel (Mytilus edilus) stock assessment, Outer Ards, Northern Ireland 2019-01-08 publication 2021-11-10 revision 2018-07-25 creation DASSHSE00000053 This dataset contains presence/absence information of infaunal bycatch from seed mussel stock (Mytilus edulis) assessment surveys off the Outer Ards Peninsula in Northern Ireland. The seed mussel survey is carried out each year and this particular dataset contains the bycatch information from initial ground truthing (dredge) on these surveys from 2017-02 to 2018-07. The dredge samples are taken from the DAERA Fisheries Protection Vessel Queen of Ulster (formally Banrion Uladh). The main aim of the seed mussel survey is to carry out a stock assessment of seed mussel in areas that are fished for these mussels. The stock assessment surveys use acoustic ground discrimination system (AGDS), dredge surveys (ground truthing) and then in areas where there appears to be high levels of seed mussel an underwater video camera sledge is towed from the RV Corystes for more ground truthing. In total there were 42 dredge tows carried out that contained bycatch in this dataset. It is important to note that the information in this dataset was not the key focus of these surveys. The most common species found were Laminaria species. Catherine Gibson Agri-Food and Biosciences Institute (AFBI) Catherine.Gibson@afbini.gov.uk owner Data Archive for Marine Species and Habitats (DASSH) Data Archive for Marine Species and Habitats Data Manager 01752426237 dassh.enquiries@mba.ac.uk custodian Catherine Gibson Agri-Food and Biosciences Institute (AFBI) Catherine.Gibson@afbini.gov.uk originator Data Archive for Marine Species and Habitats (DASSH) Data Archive for Marine Species and Habitats Data Manager 01752426237 dassh.enquiries@mba.ac.uk distributor continual Marine Environmental Data and Information Network MEDIN metadata record availability 2025-06-10 revision NDGO0005 NDGO0005 2025-06-10 revision Habitats and biotopes GEMET - INSPIRE themes, version 1.0 2021-09-28 revision Fishing by-catch Zoobenthos generic abundance SeaDataNet Parameter Discovery Vocabulary 2021-09-28 revision Marine UNESCO 2003-01-01 revision otherRestrictions Open access; CC-BY (https://creativecommons.org/licenses/by/4.0/) otherRestrictions Open access 10 English 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646 biota economy oceans -5.5413 -4.9370 54.2648 54.7249 SeaVox salt and freshwater body gazetteer 2021-01-06 creation North Channel ICES Rectangles 2021-01-06 creation 38E4 2017-02-21 2018-07-25 SeaVoX Vertical Co-ordinate Coverages 2021-01-06 revision water column Delimited https://doi.org/10.17031/uknai3 DOI Link A link to the web service or dataset dataset MEDIN data guideline for fish and benthos data by trawl or dredge 2018-10-08 publication See the referenced specification true Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication mandatory true This dataset contains information on the presence and absence of bycaught infauna species during the stock assessment surveys of seed mussel (Mytilus edulis) in the Outer Ards Peninsula in Northern Ireland in 2017 and 2018. As this dataset contains bycatch data it is important to note that the infauna were not the key aim of the survey. The seed mussel stock assessment is carried out with the aim of providing a comprehensive assessment of the state of the seed mussel beds which are commercially fished. Initially a RoxAnn acoustic ground discrimination system (AGDS) using a 200kHz transducer collected data on the roughness and hardness of the substrate at a save rate of 1s. This acoustic device was deployed off the Fisheries Protection Vessel Queen of Ulster (formally Banrion Uladh). A dredge survey was then carried out from the Queen of Ulster using a custom oyster dredge (1.5m x 0.5m) following the AFBI Standard Operating Procedure (SOP) Collection and recording of benthic dredge samples. In total there were 42 dredge tows carried out that contained bycatch in this dataset. The bycaught species were identified as accurately as possible and recorded (presence/ absence). A towed epibenthic video sledge was used from the RV Corystes to provide further ground truthing information for the stock assessment (this information is not present in this dataset). A Konsberg video camera, halogen lights and point lasers (for scaling) were all attached to the camera sledge and towed at an estimated speed of 0.5-0.8 knots. The footage was reviewed by experienced marine biologists.