This project is the first of a larger strategic focus that moves away from species based management towards integrated ecosystem management. It will give impetus to:

a) Understanding the implications of management of one resource on another,
b) Measuring the impacts of increased utilisation of the marine ecosystem on the health of all components of the ecosystem (eg. commercial and recreational fishing, tourism, aquaculture),
c) Establishing baseline data that can be used to monitor environmental change (e.g. introduced pests, global warming),
d) Meeting the increasing need of consumers for environmental accreditation (e.g. MSC, EA). This is particularly the case for diversification of future markets.

This project addresses several aspects of Australia’s Marine Science and Technology Plan.
Program 1 - Understanding the Marine Ecosystem
Objective 6: To understand the biological processes in Australia’s oceans
Objective 7: To understand the dynamics of Australia’s marine habitats and ecosystems
Program 2 - Using and Caring for the Marine Environment
Objective 1: To ensure the maintenance of healthy and properly functioning ecosystems through the development and application of effective monitoring and assessment procedures and sustainable management practices
Objective 6: To improve the productivity and sustainablilty of wild harvest fisheries, and to improve understanding of the relationship between fished stocks and the ecosystems that support them.

The project addresses FRDC's strategic vision to move towards assessment and management of Australia’s fisheries at the ecosystem rather than single species level. A concern in embracing integrated multi-species or ecosystem-based management is the breadth of ecosystem issues that can be tackled. By focusing on specific issues identified by our stakeholders this project has the potential to demonstrate the benefits of multi-species management in two of SE Australia’s most valuable fisheries, and the need for this approach to be adopted as the future management framework.

The need to develop and apply new methods is core to improving our understanding of marine ecosystems. This project encompasses this need with the use of infra-red and low light video technology, acoustic telemetry and DNA dietary studies, all of which represent frontier technologies.

At the TasFRAB Wildfish Strategic Planning Workshop held in 2003 to develop Tasmania’s 2004 – 2009 Strategic Fisheries Plan, both Industry and Government recognised that a healthy and productive reef ecosystem is essential for maximising the social, economic and aesthetic returns to rural coastal populations in Tasmania.

At the Southern Fisheries Management Workshop (SFMW) held in November 2003, managers highlighted three separate approaches that needed to be addressed in pursuing ecosystem based management. These were a systems approach that described a management unit and incorporated all inputs into the system (e.g. Westernport Bay and associated catchments, Great Australian Bight), a risk assessment approach and an understanding of processes that drive systems. TAFI's approach that focuses on understanding process based on observed patterns was endorsed by the SFMW. It was noted that TAFI was in the best position to undertake this research in a cost effective manner as this approach suited post-graduate studies.

Abalone culture is a rapidly expanding industry, both in Australia and other countries, where sea-based growout systems are common. Presently the most successful commercial abalone farming operations in Australia are land based, although there is a trend towards the establishment of sea based operations in South Australia, Victoria, Western Australia and possibly New South Wales, in addition to the established operations in Tasmania. The establishment of a successful sea cage abalone culture industry depends primarily on overcoming the problems of high mortality due to mudworm. Successful establishment of this sector of the abalone culture industry, in Tasmania and elsewhere, will enhance the stability and viability of abalone culture in Australia, enabling better competitiveness with overseas producers.

Sea cage culture offers a lower capital investment strategy to a land based operation, and is therefore the best option for some small operators. In addition it represents a cost effective alternative for grow out of larger stock produced in land based operations. The involvement of three of Tasmania's largest salmon producers in sea cage abalone culture is indicative of the potentially valuable means of diversification for existing marine farmers that sea cage abalone farming represents. Additionally, sea based culture represents the most viable means of long term culture of abalone necessary for the production of large animals for products such as pearls.

Mudworm infestation also affects land based operations, causing elevated mortality levels, and reduced growth. In addition, other cultured molluscs, particularly oysters, are prone to mudworm infestation. Advances in mudworm control through improved management strategies will therefore assist the viability of these industries.

Any strategic approach to the control of mudworm, with or without the use of chemotherapeutants, will need to be based on an overall management approach. Consideration will need to be given to such factors as the ecological and hydrodynamic characteristics of sites, the design, placement and maintenance of cages, husbandry practices and management of stock. Clearly the development of such a strategy requires substantial baseline data on the epidemiology of the parasite and the biology of the host/parasite interaction, an area in which there is currently a paucity of information.

It has become apparent to commercial divers within the NSW abalone fishery that previously productive areas of reef are now supporting high densities of sea urchins, and correspondingly low densities of abalone. This change has contributed, together with pressure from the commercial and recreational fishery, illegal poaching, disease and pollution, to a decline in the sustainable yield from the population. The current development of the sea urchin fishery in NSW provides the opportunity to re-establish populations of abalone on once productive areas of reef over a large spatial scale. Natural recolonisation of areas of reef will be limited because of the restricted dispersal of larvae from their parents.

A variety of techniques are already being used to help re-establish populations of abalone on depleted areas of reef in NSW. These include the clearance of sea urchins to allow natural recovery, together with the transplantation of broodstock to help increase the speed of recovery. All these techniques are very labour-intensive. The deployment of seed produced from wild abalone provides a significantly more powerful technique to rapidly enhance populations of abalone on depleted reefs over a large-scale. Protocols for the conditioning, spawning and rearing of blacklip abalone are already well established and provide the framework for the year-round production of seed. Techniques for the large-scale deployment of seed have been developed in other states, but recent advancements in our knowledge of settlement substrates suggest further improvements can be made. Similarly, deployment techniques will need to be adapted for the unique conditions on reefs in NSW, and particularly the presence of the sea urchin, Centrostephanus.

With the development of techniques to allow the successful, large-scale release of abalone seed to coastal reefs in NSW, there are likely to be significant benefits to the associated fisheries. In particular, the potential exists for increases in the sustainable yield of the fishery of up to several hundred tonnes per year, or several million dollars.