Yellowtail kingfish (YTK) farming is identified nationally as the greatest opportunity for new aquaculture development in the next few decades through substantial increases in farmed area and product, and use of aquafeeds, resulting in growth in regional economies and employment. Within 10 years, YTK production is expected to increase by 34,000 tonnes, worth $440 million, and using 68,000 tonnes of aquafeed worth $136 million. The key challenge to achieving this growth is for industry to diversify its focus from supplying only the relatively small volume, high price sashimi market to the larger volume, lower price Australian "white fish market", while enhancing farm productivity and reducing operating costs to maintain profitability. This project will enable industry to grow its position by developing more cost effective, sustainable feeds and feeding strategies to enhance YTK growth and health; the industry's highest common R&D priorities as feed and feeding strategies comprise 60% of operating costs. It will also network two key Australian YTK aquaculture companies and their aligned research institutions (SA and NSW). A third producer (WA) and aquafeed companies are likely to invest in subsequent years. As such, this project will meet the designated 'Rural Research & Development for Profit Programme' objectives:

1􀀑􀀃. Generating knowledge, technologies, products or processes that benefit primary producers,
2􀀑􀀃. Establishing and fostering industry and research collaborations that form the basis for ongoing innovation and growth of Australian agriculture.

The key Activities wil address the YTK industry's common R&D priorities through three components/themes:
1. Economically sustainable feeds and improved diet formulation (NUTRITION);
2. Improved FEEDING STRATEGIES to increase profit; and
3. Improving nutritional HEALTH to boost productivity.

Once the project is initiated the Steering Committee will develop an agreed approach to engage with aquafeed companies to maximise participation in and contribution to the project.

This project directly addresses Priority 20 in Program 1 (Environment), which was identified as a research priority by the NSW Fisheries Research Advisory Board for 2015. This priority arose through ongoing concerns about declines in School prawn productivity that fishers have conveyed to NSW commercial fisheries managers and peak industry bodies, particularly fishers in the north coast region of NSW. This issue is not confined to one estuary, and declining productivity of School prawns in some areas is an issue which percolates through all stakeholders in the NSW fishing industry, including individual fishing businesses and fishing cooperatives at the local scale, as well as the Professional Fishermens Association and other peak bodies, and recreational fishers whose primary bait supply is underpinned by School prawn harvest.

Consequently, this project has been designed to address two key needs identified by industry: 1) An improved understanding of the specific issues within Camden Haven estuary, to allow management to strategically target ameliorative actions within the catchment and estuary itself; and 2) A broader understanding of how catchment-based activities could be affecting School (and other) prawn stocks along the New South Wales coast, through adverse effects on water quality. Restoration of the School prawn fishery in Camden Haven and other estuaries is essential to the continued livelihoods of estuary fishers, and provision of quality seafood product for both consumption and bait markets. However, the factors which have contributed to the declines in catch must be understood if ameliorative/restorative actions are to be implemented in a strategic fashion. These factors may include a combination of both recruitment and water quality issues. Furthermore, ~25% of seagrass was lost from the system between 2005 and 2011, which may also have contributed.

NSW currently imports over 85% of its seafood and needs a substantial increase in investment and production, most notably, major new marine based aquaculture development.(Bond University, 2012). However, marine aquaculture development is fundamentally constrained by the lack of background biological and economic information. To promote marine finfish production, the NSW government has invested significantly in establishing, through the normal application pathway (EIS, REF, public consultation, DA), a 20 ha Marine Aquaculture Research Lease (MARL) off Port Stephens with approval to produce up to 300 t fish/annum. The MARL is a vehicle to streamline approvals process, foster the social licence required for finfish production expansion in NSW, and to provide the fundamental information needed to encourage investment.

There are three key end users for MARL research: Industry, Public and Regulators. The research proposed on the lease will address short term needs central to the development of fish farming in subtropical waters of the Australian east coast and develop a platform for ongoing research.
DPI has begun dialogue with potential commercial partners to operate the MARL. These discussions have established that yellowtail kingfish (YTK) is the primary species of interest (although tuna is a candidate and is specifically approved for the MARL). This interest in YTK is in part is driven by a shortfall of Kingfish and Barramundi from aquaculture in local markets – of the order of 460 t at the Sydney Fish Market alone last financial year.

Industry need: YTK production within Australia has not been without its challenges and further research is essential, particularly when entering new farming environments. Previous CRC research (SFCRC 2008/903) has developed models showing rapid growth for YTK in warmer waters (18 months to 4.5 kg), but these models need validation. Further, there is a need to investigate health challenges and potential management options in a new offshore environment.

Public need: In gaining approval for the MARL, extensive public consultation was undertaken that identified key concerns with respect to the sustainable operation of the MARL. Traditional concerns over nutrient enrichment arose but were overshadowed by issues related to potential impacts on species of sharks and cetaceans. There is a need to investigate the MARL interaction with these species, and Port Stephens is uniquely well placed for this to occur. Port Stephens has the most intensive cetacean watch industry in the world and is the focus of a juvenile white shark and grey nurse shark monitoring program.

Regulatory need: DPI is funding development of a Marine Waters Sustainable Aquaculture Strategy for NSW (MWSAS), under State Environmental Planning Policy 62 – Sustainable Aquaculture (SEPP62) to streamline investment pathways and promoting sustainable seafood production. A MWSAS will describe the approvals process, best practice system design and operation, and identify areas suitable for future development. MARL research will inform a MWSAS in key areas of sustainability

This project addresses the 2013 NSW FRAB research priority “Understanding environmental impacts on commercially important species”. The paucity of knowledge of EKP nursery habitats in NSW is a significant problem, as the estuarine nursery phase is the period where EKP are most likely to be affected by (non-fishing) anthropogenic activities and potentially represents a recruitment bottleneck which directly affects productivity. Investment in research in the southern United States has found that:
1) There is quantitative relationship between intertidal vegetation and the yield of penaeid prawns (Turner, 1977);
2) Restoration of connectivity and rehabilitation of saltmarsh areas has a quantifiable benefit for prawn fisheries (Rozas et al., 2005).

Research into estuarine nursery habitats for EKP in south-eastern Queensland forms the basis of the sustainable management of their prawn fishery through a recruitment index. In NSW, however, there is a paucity of knowledge on the early life history stages, including recruitment to estuaries, use of estuarine habitats by natural recruits, and factors that affect growth and survival of young EKP. Regulating river flows in estuaries and restricting tidal flow into wetlands can destroy connectivity between new recruits and their nursery areas. NSW commercial fishers have indicated that wetlands in the lower portion of estuaries (such as Hexham Swamp in the Hunter River) were historically significant nursery areas for EKP, prior to their destruction. These anecdotes highlight a need to understand the nursery habitats and hydrographic conditions that contribute to the EKP fishery in NSW. An understanding of the nursery function of these areas, the extent of habitats lost, remaining and restored, is required to provide a basis for assessing the competing costs and benefits of habitat rehabilitation. Further, this project represents an important case study to highlight the potential financial benefits to fisheries of rehabilitation and restoration of appropriate estuarine habitats.