Crayfish (Palinurus elephas): Catch and bycatch in the tangle net fishery off the southwest coast of Ireland in 2021-2024

The spiny lobster or crayfish (Palinurus elephas) fishery off the southwest coast of Ireland has expanded rapidly in recent years, driven by increased catch rates and high market value. This study quantifies catch, bycatch, fishing effort and spatial distribution in the tangle‑net fishery from 2021 to 2024 in two fleet areas, Tralee Bay and Dingle Bay. Data were collected using scientific observer coverage, contracted skipper self‑reporting at haul level, and continuous inshore Vessel Monitoring Systems (iVMS), enabling reported data to be raised to vessel and fleet levels for the first time. Crayfish landings and fishing effort increased substantially over the study period, with catch rates doubling since 2017 and remaining high through 2024. Crayfish mortality in tangle nets averaged 7.2% and increased with net soak time, with higher mortality observed in Tralee Bay. Bycatch was dominated by invertebrates and low‑value fish, but significant incidental capture of endangered, threatened and protected species occurred. Fleet‑level estimates indicate substantial bycatch of grey seals (Halichoerus grypus) and critically endangered elasmobranchs, including angel shark (Squatina squatina) and flapper skate (Dipturus spp.). Bycatch risk was spatially structured, with higher seal bycatch near haul‑out sites. The results indicate that the tangle‑net crayfish fishery poses serious conservation risks, and highlight the need for effort management, improved spatial protection, and transition to low‑impact fishing gears.

URI

https://oar.marine.ie/handle/10793/2081

Description

Primary fund: European Maritime, Fisheries and Aquaculture Fund (EMFAF) 2021–2027 Managing Authority: Department of Agriculture, Food and the Marine (Ireland) Beneficiary / Implementing body: Marine Institute Key contract reference: ITT21‑019 Related earlier project refs: MB/2017/11, MB/2019/01 (EMFF Marine Biodiversity Scheme)

Citation

Palma Pedraza, S. and Tully, O. (2025). Crayfish (Palinurus elephas): Catch and bycatch in the tangle net fishery off the southwest coast of Ireland in 2021-2024. EMFAF Marine Institute Report Series. Galway, Ireland