Bycatch of endangered, threatened and protected species of marine mammals, seabirds and marine turtles, and selected fish species of bycatch relevance

ICES summarizes estimates of the annual numbers of specimen taken as bycatch (annual bycatch) and multiannual bycatch rates of endangered, threatened, and protected (ETP) species of marine mammals, seabirds, marine turtles, and fish, based on reported bycatch and monitoring data received through ICES data calls.

Annual bycatch estimates in 2023 are provided for 116 ETP species as part of 316 combinations of species, fishing gear (métier level 4), and ecoregion. Among these ETP species are 12—2 marine mammals, 3 marine turtles, 1 seabird, and 6 fish—from DG MARE’s list of 26 priority species. Subregional estimates are also provided for 103 combinations of ETP species, métier level 4 and ICES subdivisions/Mediterranean GSAs, including 6 priority species.

For priority marine mammals, seabird and marine turtles, ICES notes the highest estimated bycatch of short-beaked common dolphin (Delphinus delphis) is in set gillnets (GNSs) and trammel nets (GTRs) in the Bay of Biscay and the Iberian Coast ecoregion. The highest estimated bycatch of harbour porpoise (Phocoena phocoena) is in GNSs in the Norwegian Sea ecoregion. The highest bycatch of loggerhead turtle (Caretta caretta) is in bottom otter trawls (OTBs) in the Adriatic Sea ecoregion. An annual bycatch estimate is provided for the Balearic shearwater (Puffinus mauretanicus) in GTRs in the Bay of Biscay and the Iberian coast ecoregion.

Annual bycatch estimates of priority fish are provided for Adriatic sturgeon (Acipenser naccarii) in OTBs in the Ionian Sea and the Central Mediterranean Sea ecoregion; beluga sturgeon (Huso huso) in midwater otter trawls (OTMs) in the Black Sea; angel shark (Squatina squatina) in GTRs and GNSs in the Celtic Seas ecoregion; common skate (Dipturus batis and Di. intermedius) in four ecoregions; and spiny butterfly ray (Gymnura altavela) in OTBs in three ecoregions.

To improve accuracy and precision in estimates of annual bycatch and multiannual bycatch rates, ICES advises (i) to increase monitoring effort in area/métier combinations identified as high priority for bycatch monitoring and (ii) to prioritize at-sea observers and electronic bycatch monitoring protocols.

ICES reiterates that reporting of complete fishing effort and monitoring effort data for all métiers, even when no bycatch has been reported, is needed for bycatch assessments.

ICES summarizes available abundance estimates for priority ETP species and notes that bycatch sustainability thresholds exist for some species. It is a priority to evaluate such thresholds for alignment with available population estimates and management objectives.