Attendance at the Annual Session of the Western and Central Pacific Fisheries Commission (WCPFC) - 4-9 December 2018 in Honolulu, USA
As an investor in one of the few new-build tuna longline vessels on the East Coast, Hayley Abbot has a strong personal interest in the future sustainability of the Eastern Tuna and Billfish Fishery (ETBF). Given the highly migratory nature of the target species (including yellowfin, bigeye, albacore and billfish) the future of the ETBF is inexorably linked to the status of the resource in the western Pacific and decisions made at the Western and Central Fisheries Commission (WCPFC).
With this connection, there is a need for fishers to have an understanding of, and where possible have industry input into, the international aspects of the management of the fishery.
Hayley has the potential to become a young industry leader in Australian fisheries. To achieve her potential, there is a need to expose her to a wide variety of relevant fisheries experiences - this opportunity will provide one of those experiences
At a personal level, Hayley will benefit greatly from gaining an understanding of the wider international context management of the fishery, the major industry players, researchers (SPC )and managers (FFA and other national delegations). Hayley will be able to use this knowledge, and especially the interaction with researchers, to enhance my input into ComRAC. The experience will build both her leadership experience and confidence.
Final report
Investigate oceanographic and environmental factors impacting on the ETBF
As specified in the FRDC call for proposals, there is a need for AFMA, its advisory committees and the ETBF industry to gain a much stronger understanding of past, current and potential future oceanographic and environmental impacts upon (i) the spatial and temporal distribution and level of ETBF catches, catch rates, fishing effort and fish sizes (particularly those indicators used in the ETBF harvest strategy), and (ii) the interactions between focal species in the ETBF with domestic (e.g. recreational) and international fisheries. We have established relationships with regional partners, and pending endorsement, which will allow comprehensive collation of catch and tracking data for the focal species, such that habitat models for the whole region can be developed. This will permit hypotheses about movement of fish cohorts into the Australian region, and movements of these fish within the Australian EEZ to be tested.
This proposed research is needed to ensure the effectiveness (note, the ETBF already has a developed HS) and further development of appropriate management arrangements, including harvest strategies and resource sharing arrangements. It will complement current genetic research into stock structure and connectivity, with implications for harvest strategies and potentially Australia’s position on key management issues and approaches being considered or developed in the Western and Central Pacific Fisheries Commission (WCPFC). By collating data from the countries in the south-west Pacific Ocean and New Zealand regions, we will seek to understand patterns in regional abundance. Importantly, this project will provide insights into potential long term changes in the ETBF that may result from climate change, and deliver forecasting capability on seasonal and decadal time scales. We will identify the influence of any large scale oceanographic drivers on availability of these key species in Australian waters, such as the strength of the East Australia Current, or the teleconnections resulting from ENSO events.
Final report
Project products
Delivery of focused corporate governance training by the Australian Institute of Company Director's to the newly formed Tuna Australia Ltd board representing stakeholders of the Commonwealth managed Eastern Tuna and Billfish Fishery
Determination of the spatial dynamics and movement rates of the principal target species within the Eastern Tuna and Billfish Fishery and connectivity with the broader western and central Pacific Ocean – beyond tagging
Management of the ETBF is complex because of the cross-jurisdictional nature of the stocks and governance through the Commonwealth Harvest Strategy Policy and the WCPFC. Current assessments conducted by the WCPFC assume that these species comprise either single discrete stock units throughout the WCPFC area or across the Southern Hemisphere portion of the region and genetic methods used in the past have been unable to refute such assumptions. Biological information on growth rates and reproduction, movement data derived from tagging studies and spatial and temporal variability in catches of these species however, suggest that there is likely to be some structure to stocks throughout the WCPFC region and assumptions of single spawning populations may not be accurate.
More recently, traditional and next generation genomic methods have provided evidence of population structure in yellowfin tuna across the Pacific (e.g. Aguilar et al. 2015; Grewe et al. 2015) and provide some support to the hypothesis that yellowfin tuna fished by Australia’s tuna fisheries may be a localised stock within the Coral and Tasman Sea region. If yellowfin tuna and if any of the other principal species occurring in the ETBF do comprise localised stocks, this has obvious implications for the management both within national and regional contexts. Clarification of the connectivity and population structure of species in Australia’s Tropical Tuna fisheries with the broader WCPFC region is required for appropriate governance through the Commonwealth Harvest Strategy Policy and the WCPFC, to ensure any risks to regional stock biomass are minimised and to improve stakeholder concern over stock management.
Final report
The results of the current study are largely consistent with previous genetic investigations into the population structure of these four species. Consistency in results across years suggest that the groupings revealed here have some temporal stability across years across those sites where multiple years of samples were collected. Although results suggest the potential for two genetic groupings among albacore samples, assignment by the methods used here was statistically uncertain and resulted in some individuals not being able to be assigned to either group in the scenario with any confidence. Further sampling from the three locations included here as well as inclusion of samples from additional sites would also be required for resolving these uncertainties.
It should be noted that these results only apply to the sites included for each of the species in this study and therefore cannot be extrapolated across the wider western and central Pacific Ocean region with any certainty. Further sampling and analysis of sites across the western and central Pacific, including temporal replication of sampling, would be needed to investigate whether the results presented here are consistent with other locations across the western and central Pacific region or whether greater genetic differentiation is discernibly present. The resources required to support the attainment of broader insights into the connectivity of species across the WCPFC Area and connectivity between the ETBF and the western and Central Pacific Ocean will be dependent on current access to samples, the extent of further sampling required in order to attain broad spatial and temporal coverage of samples, the facilities and capability available for processing and sequencing samples and the capability available for data quality control and analysis pipelines.
As next steps, a second year of sampling for broadbill swordfish from New Zealand is planned and a preliminary small dataset from the Cook Islands (consisting of 24 samples) has been collected. These samples will be analysed and incorporated with the data from this project to provide further insights into the connectivity of broadbill swordfish across the western and central Pacific Ocean and presented to the WCPFC Scientific Committee in August 2021.