Update on Antipodean albatross tracking and overlap with pelagic longline fishing effort

Citation
Bose S, Fischer JH, Debski I, et al (2023) Update on Antipodean albatross tracking and overlap with pelagic longline fishing effort. In: WCPFC Scientific Committee 19th Regular Session. WCPFC-SC19-2023/EB-IP-06, Koror, Palau
Abstract

Bycatch in fisheries is the greatest known threat to the endangered Antipodean albatross (Diomedea antipodensis antipodensis) population, which has been declining at ~5% per year since 2005. We update findings presented to SC18 on the first two years of an intensive satellite tracking programme, having now deployed 219 tags on Antipodean albatross over four years. The findings show that whilst the general distribution of tracked birds is consistent across years, stretching across the Pacific from Australia to Chile, there are interannual differences. The year-to-year variation may be driven by multiple factors including the differing sampling priorities in each year as well as potential climatic and oceanographic differences which are yet to be explored. Our initial assessment of overlap of all tracked Antipodean albatross with pelagic longline fishing effort confirm that the areas of highest relative overlap occur in the WCPFC area, both in the mid-Tasman Sea and to the North-East of New Zealand. The majority of overlap occurs in the High Seas. A key finding is that whilst the area north of 30° South forms only a modest portion of the overall distribution of tracked Antipodean albatross, there is overlap with increased pelagic longline fishing effort in the area between 25° and 30° South in the WCPFC area. Under CMM 2018-03 specifications, only one mitigation measure is required to be used in the area 25° 30° South, and as such fishing effort poses a higher risk of bycatch. Further work is currently underway to fully analyse the complete four-year tracking data set which we intend to report to SC20.