7a4ec575-229f-496a-9cc2-6a593770b1ce English dataset Leo Clarke Bangor University School of Ocean Sciences leo.clarke@liverpool.ac.uk pointOfContact 2025-03-06 MEDIN 3.1.2 EPSG Geodetic Parameter Registry 2021-01-06 revision WGS 84 2025 Bangor University Bycatch in Welsh Static Net Fisheries Observer Data Monitoring bycatch in Welsh static net fisheries through onboard observer data collection 2023 - 2025 Bycatch in static nets Wales 2025-03-06 publication 2025-01-21 revision BU_FISP_BSN This Fisheries Industry Science Partnership project was a collaboration between Bangor University, Natural Resources Wales and the Welsh Fisherman's Association, to assess bycatch in static net fisheries in Wales from 2023 - 2025. An onboard observer program was conducted during netting operations on small scale commercial vessels and during commercial shore netting in Welsh inshore waters. Observers collected data on species catch (target and bycatch) with associated length, weight, vitality and sex data (when possible), fishing effort (duration of fishing activities), GPS locations of fishing activities, and gear characteristics (gear type, net length, mesh size). For data collection reasons only relevant available metadata is published. Leo Clarke Bangor University School of Ocean Sciences Metadata contact leo.clarke@liverpool.ac.uk owner Leo Clarke Bangor University School of Ocean Sciences Metadata contact leo.clarke@liverpool.ac.uk custodian Leo Clarke Bangor University School of Ocean Sciences Metadata contact leo.clarke@liverpool.ac.uk originator Leo Clarke Bangor University School of Ocean Sciences Metadata contact leo.clarke@liverpool.ac.uk distributor notPlanned Marine Environmental Data and Information Network MEDIN metadata record availability 2025-03-06 revision NDGO0005 NDGO0005 2025-03-06 revision Environmental monitoring facilities Species distribution GEMET - INSPIRE themes, version 1.0 2021-09-28 revision Fish abundance in water bodies Fishery characterisation Fishing by-catch Fishing effort SeaDataNet Parameter Discovery Vocabulary 2021-09-28 revision otherRestrictions Restricted public access due to commercially sensitive data of catch and spatial data on fishing activities. otherRestrictions Restricted access and use. No conditions apply, the data cannot be used by the public. English 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646 biota economy oceans -3.197021484375 -3.109130859375 51.395564180331 51.641672200851 -5.5810546875 -3.18603515625 51.344338660599 53.663764258508 SeaVox salt and freshwater body gazetteer 2021-01-06 creation Irish Sea Charting Progress 2 Sea Areas 2021-01-06 creation Irish Sea ICES Statistical Areas 2021-01-06 creation VIIa ICES Statistical Areas 2021-01-06 creation VIIg 2023-10-13 2025-01-21 0 43 Database dataset 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 The metadata complies with MEDIN Discovery Metadata Standard 3.1.2. true MEDIN data guideline for static net, pot and trap data 2011-01-28 publication The metadata conforms with the MEDIN data guideline for static net, pot and trap data. true Observer data was collected as part of a FISP funded research project on bycatch in Welsh static net fisheries. Additional fisher self-reported data were used to supplement the observer data and enhance coverage. An ethical review process was performed prior to data collection and all fishers involved were MCA certified. Data were collected on 116 days from 13th October 2023 until 21st January 2025. A total of 7 commercial fishing vessels participated on a voluntary basis in both the observer programme and in providing self-reported data. Data collection was conducted in North Wales (ICES subdivision 7a) and South Wales (ICES subdivision 7g). Bycatch of all species including marine mammals, seabirds, elasmobranchs and diadromous fish were recorded across inshore areas of Wales where small commercial net fisheries operate. Count data was collected on all species captured, including target catch and bycatch. Catch data were recorded for each set, individuals were recorded at species level and biometric measurements (length and weight) were taken where possible, as well as the condition (dead or alive) and outcome (retained or discarded) recorded for each individual Species were weighed using motion compensating scales or digital scales and a sling for larger species. Individual length measurements were recorded using either a measuring board or a tape measure (depending on the size of the individual). Measurements were recorded differently for each taxonomic group: marine mammals: total length; seabirds: wingspan (left wingtip to right wingtip) and total length (bill tip to tail feather tip); elasmobranchs: total length for sharks or disc width for rays/skates; teleost: total length; crustaceans: carapace width for crabs or carapace length for lobsters. Sex of the animal was identified when possible. Metadata (site, haul and set dates and times, vessel characteristics, soak time, net characteristics etc.) were recorded for every net hauled even in the absence of target catch or bycatch to account for all effort. A Garmin handheld GPS was used to collect vessel tracks and gather coordinates when hauling for the start and end of fishing nets, with associated time data. GPS data was used to create maps of observer effort and fishing effort in QGIS. Catch data was used to calculate estimates of bycatch per unit effort (BPUE) across different taxonomic groups, species and net types. All data were manipulated and prepared for analysis in R Studio. Calculations of mean BPUE rates (and associated bootstrapped 95%CI’s), analysis of catch composition, outcome and condition proportions were all conducted in R. Generalised linear mixed models were conducted using the glmmTMB package to model BPUE rates against various predictor variables. Multivariate analysis comparing patterns in species composition across factors (net type and season) and identifying environmental variables and particular bycatch species which best explain the variation in species composition were conducted in PRIMER 7.