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.