Effectiveness of Conservation and Management Measures for reducing seabird bycatch on pelagic longlines in the South Atlantic

The ICCAT Sub-Committee for Ecosystems and Bycatch (SC-ECO) has been tasked to review Conservation and Management Measures (CMMs) designed to reduce incidental seabird bycatch on pelagic longlines in the south Atlantic, following ICCAT Recs 07-07 and 11-09. Here we evaluate the evidence for different combinations and specifications of the currently accepted CMMs between current ICCAT specifications and best practice guidance from the Agreement on the Conservation of Albatrosses and Petrels (ACAP)’s seabird bycatch working group. We also consider the efficacy of hook shielding devices (HSDs) as an alternative to the existing measures for reducing seabird bycatch. We apply an ecological risk assessment approach (EASI-Fish), reviewed previously in SC-ECO, and applied elsewhere, to five populations of four at-risk albatross and petrel species in the Atlantic. Seabird fisheries bycatch rates are believed to be under-reported, and so we adopted a riskbased approach to understand patterns in bycatch rates between different combinations and specifications of conservation measures, and implications for threatened seabird populations. We concluded that updating the CMMs for pelagic longlining in the South Atlantic to reflect current best practice guidelines was likely to reduce seabird mortality by 43 – 75 % when maintaining the current approach where operators are allowed to select two of three possible CMMs. Mandating that all three CMMs be applied simultaneously to ACAP best practice guidelines, or the use of hook shielding devices, was likely to reduce seabird mortality by 83 – 96 % compared with existing measures. None of the proposed amendments to CMMs are expected to significantly affect catch rates of target species or other non-retained bycatch species.

RECOMMENDATIONS 1. Acknowledge an ecological risk assessment approach is a useful method to understand patterns in bycatch rates between different combinations and specifications of seabird bycatch mitigation measures in the absence of accurate reporting of bycatch. 2. Acknowledge the findings of the paper, which corroborates that implementation of conservation management measures according to ACAP best practice guidelines reduces seabird bycatch to a greater degree than currently mandated ICCAT conservation and management measures. 3. Note the conclusions of this paper regarding the most effective implementation of seabird bycatch mitigation measures to reduce seabird bycatch in the South Atlantic.