Seabird warp strike observation protocols for trawl fisheries

In 2023 the Scientific Committee endorsed the recommendation from WG-IMAF to consider requiring observers to make species specific estimation of bird abundance around the vessel prior to each warp strike observation, noting that this will impact on the observers’ time for other tasks and potentially require additional training. This recommendation was based on advice from ACAP seabird warp strike observation protocols for trawl fisheries, presented in WG-IMAF-2023/05. This paper distils and adapts key elements from WG-IMAF-2023/05 to present recommendations for a suitable CCAMLR SISO protocols for trawl fisheries, mindful of minimising additional demands on observer capacity. As highlighted in WG-IMAF-2023/05, heavy warp strikes are likely to be rare events in absolute terms compared to the frequency of bird occurrence in danger areas around the warps (which can be monitored through seabird abundance counts) and light warp strikes. Hence, collecting information on seabird abundance is a more data rich proxy measure for quantifying the relative risk to seabirds (from heavy warp strikes). Here, ACAP provides advice on methodologies for the estimation of abundances of seabirds attending fishing operations