Deep-water finfish are an increasingly important fisheries resource on Australia's east coast that has been subjected to recent and rapid growth in fishing pressure across commercial, recreational, and charter sectors. Drivers of increased targeting of deep-water species likely include depletion of inshore stocks leading to effort shifts to deeper areas, advances in technology facilitating more effective targeting of deep-water species and changing market dynamics leading to increased profitability. However, sustainable management of deep-water finfish stocks requires species-specific information on fundamental life history characteristics and stock structure to inform evidence-based management that is currently lacking.

Deep-water species are often characterised by slow growth, late maturity, and clustered distributions around pockets of suitable habitat that leave them vulnerable to overfishing. It is necessary to determine how such traits and connectivity among populations affect the sustainability of fisheries for key deep-water species on Australia's east coast. Management of deep-water species is also complicated by cross-jurisdictional distributions including Queensland, New South Wales, and Commonwealth managed fisheries.

Currently, due to the lack of fundamental biological information, key deep-water species are managed using basic harvest strategies set to trigger enhanced management and scientific focus when such need arises, which is now occurring. For example, the 2021 commercial harvest of Bar Cod (Epinephelus ergastularius) in Queensland exceeded double the mean harvest from 2011-2015, triggering a requirement for the first stock assessment of this species. Anecdotally, recreational catches in Queensland of other key species including Flametail Snapper (Etelis coruscans) and Goldband Snapper (Pristipomoides multidens) have substantially increased in recent years, with the latter given priority status for future stock assessment. New South Wales DPI has indicated a particular need for research focus on Bass groper (Polyprion americanus) and Hapuku (Polyprion oxygeneios) due to the complete lack of biological information required for fisheries management of these species, both of which are now quota managed. Recreational fishing effort is important to quantify because this sector has come to dominate the deep-water fishery in some areas where commercial fishing effort is sparse. Changing fleet dynamics and the uptake of technological advances in fishing gear have also increased fishing power for deep-water species in ways that are poorly understood.

This project aims to address these issues with a cross-jurisdictional collaboration between Qld DAF, NSW DPI, and AFMA supported by the University of Queensland providing fundamental information on the biology and population connectivity of key deep-water species. Project staff are well placed to leverage their existing networks and will also build new relationships with stakeholders throughout the deep-water fishery to pursue sample collection from all available sources including commercial fishers, processors, and recreational and charter fishers. Archived samples and targeted fishery-independent sampling will also be employed to secure sufficient samples to provide confident estimates on life history parameters and population connectivity to inform stock assessment. Additionally, we aim to develop novel methods to improve recreational reporting of deep-water catches and improve estimates of fishing power effects on catches of deep-water finfish.