Abalone Aquaculture Subprogram: environmental requirements of abalone
University of Tasmania (UTAS)
The rapid expansion of the Australian abalone culture industry is being underpinned by advances in research and development that have seen tank designs and formulated diets become far more cost-effective. Market prospects are excellent (Johnston, 1996) and investment capital and available sites do not seem to be limiting factors. The hatchery sector is performing very well and its capacity is expanding rapidly. The major threat to this optimistic scenario is a decline in the health status of abalone and the most likely cause is inadequate water quality. The threat is real based on results obtained from our previous FRDC-funded, environmental requirements (bioassay) research. The 30% reduction in growth rate noted above would be enough to destroy profit margins in most aquaculture industries. We need to determine safe levels of more of the water quality variables that threaten the health of abalone and to refine the estimates for some of the variables assessed so far; greenlip abalone have proved to be even more sensitive to ammonia and nitrite than we had expected. In some states there is more emphasis on blacklip abalone culture and we need to assess that species at least in terms of its sensitivity to the most likely stressors. We also need to develop diagnostic tools for the tissue damage that these water quality variables do when outside these safe ranges so that health workers can identify the cause of a health problem in abalone. This project is compatible with the FRDC strategic plan as it is commercially attractive (prevents loss of profitability), it is feasible (the experimental system, methods and expertise have already been developed), it is collaborative (hosted by industry), has been given the highest priority by the Subprogram Steering Committee, it relates strongly to growth and survival within aquaculture development, and the species involved are primarily being produced for the Asia - Pacific market. Additionally, it contributes to export technology (live holding) and Ecosystem Protection by defining tolerances of a key commercial and recreational species.
1. Overall objective is to provide the information needed for industry to reduce its operating costs (water exchange) or increase production (through higher stocking densities) in a manner that does not compromise the health of the abalone through inadequate water quality.
2. Specifically, we aim to establish safe operating levels for a range of water quality variables
3. We also aim to identify stress-specific changes in the structure or biochemistry of abalone in relation to particular water quality problems. This will improve the diagnostic tools available to veterinary staff.
4. Finally, we plan to convey this information in a prompt and user friendly form for industry.
Principal Investigator: C.M. Burke, J. O. Harris, S.M. Hindrum, S.J. Edwards and G.B. Maguire