This project provides research support for 2 PhD students - enabling them to target their studies to issues relevant to the local salmon farming industry in particular the need for research on “Nutrient Production” identified in TSGA research priorities (2011).
Growth of salmon farming in SE Tasmania is currently limited by a feed input cap. This has arisen as a result of concerns that increased nutrients associated with salmon farming may be affecting local water quality. In addition there have been anecdotal reports that changes in macroalgal community structure, and in particular proliferation of nuisance algae species (i.e. Ulva), are related to the expansion of local salmon farming operations.
These PhD projects in combination will specifically evaluate the response of macroalgal communities to changing nutrient and environmental conditions and the implications of this for local and system wide nutrient load management.
Scott Hadley is looking to evaluate the potential to mitigate/ offset nutrient loads using target species deployment and will look at testing scenarios in a model environment to establish spatial and temporal optima for such mitigation strategies.
Whilst Luis Henriquez aims to better define the effects of changing nutrient regimes on local macroalgal communities and to measure differences in nutrient assimilation capacity of key species under differing environmental conditions.
The combined research of these students will provide a much better understanding of the driving factors behind potential "hotspots" in estuarine systems, the likely effects of these on macroalgal communities and the potential for natural and managed nutrient offsets.

The Australian salmon industry is free from the major infectious diseases affecting salmon industries in other countries. Amoebic Gill Disease is the main infectious disease affecting the salmon industry in Tasmania. While this disease occurs in other countries, it does not appear to be as severe as in Australia. The disease-related fish mortalities are greatly reduced by freshwater bathing, however the disease treatment results in greater production costs and reduces the Australian salmon industry’s ability to compete in international markets. While development of a vaccine to protect against the causative agent is a desirable solution for the industry, it must be appreciated that this is a challenging task and requires a long-term view. In the meantime, the industry needs more knowledge of AGD epidemiology and more tools to improve management of fish with AGD on the farms, which would improve AGD treatment and control and decrease the risk of large outbreaks of AGD. As a direct result this should lead to reduced production costs. Improved understanding of the epidemiology of the disease will also provide a valuable basis on which to develop strategies for vaccine application in the future.

The ultimate goal is to have an AGD surveillance system in place, to provide information about the host, agent and environment which is relevant to prevention and management of the disease. The results will improve our understanding of factors contributing to AGD outbreaks and will develop a best industry practice protocol aimed at the reduction of AGD effects on the salmon industry in Tasmania. Information from the surveillance system will facilitate better decisions on the timing of treatments as well as provide long term data for analysis to identify additional management strategies aimed at minimisation of disease risks and economic impacts. Specifically, farm-level surveillance data will eventually provide a basis for measuring spatial and temporal trends in AGD occurrence in both the host and potential reservoirs as well as environmental and production factors associated with changes in AGD occurrence. Analysis of retrospective data will permit the identification of improved management strategies as well as providing farm managers with a more reliable basis on which to make decisions on prevention and control. This project will provide ways of value adding to the data collected by the salmon industry in general. It will protect individual company interests with respect to privacy of commercial information.