A risk-based approach to rapidly screen vulnerability of cetaceans to impacts from fisheries bycatch

The potential risk to cetacean species from direct interaction with fisheries was assessed using a screening procedure based on a Productivity Susceptibility Analysis (PSA). The procedure incorporated productivity attributes specific to cetaceans; a measure of data quality to identify areas where information was lacking; a measure of the potential of different fishing gears to capture different cetacean species; and susceptibility attributes designed for scenarios with limited information on species abundance and distribution. The assessment was not temporally or spatially explicit but used examples of static and mobile gears found in Ireland, and much of Europe, to demonstrate the approach. Gillnets targeting demersal species was assessed as the fishery posing greatest potential risk to cetaceans. Pelagic trawls targeting small pelagic species was also assessed as posing moderate potential risk to cetaceans, although the risk score was lower than for gillnets. The risk of specific species-gear interactions, such as the potential for entanglement between humpback whales and pots and traps, was also identified. Designed to complement existing methods of bycatch assessment, this approach is a systematic, repeatable and standardised assessment, the outputs of which can enable the prioritization of resources for research and monitoring. The approach can be easily adapted to examine risk to cetaceans posed by fisheries around the world.