Farming seaweed for aquafeed
The feasibility of farming seaweed in association with existing ocean-based finfish aquaculture being investigated in a new project by the South Australian Research and Development Institute (Aquatic Sciences) in partnership with the University of Adelaide.
The three-year project, worth $1.1 million, is funded by the Fisheries Research and Development Corporation on behalf of the Australian Government, with contributions from SARDI and Adelaide University, along with commercial participants.
Aquaculture is an important rural industry in South Australia, with production in 2008/09 being $246 million in direct output, and with considerable potential for expansion, especially of ocean-based fish farming.
However project leader, Dr Jason Tanner from SARDI Aquatic Sciences says that with expansion comes increased feed inputs and therefore waste nutrient discharges to the environment.
"By farming seaweeds alongside finfish, these wastes could be utilized, decreasing the environmental footprint of aquaculture whilst at the same time increasing production."
The initial phase of the project will involve assessing local seaweed species for their suitability for aquaculture, as well as their economic value, and production systems in use internationally, particularly in China, where seaweed aquaculture is well established.
"There is currently very little commercial production of seaweeds in Australia, and their aquaculture is even more limited," says Dr Tanner. "As a result, Australia imports almost $20 million worth of seaweed annually. Seaweeds are used as a food source, particularly in Asian cooking, as well as for bioactive substances used in pharmaceuticals and neutraceuticals."
The second phase of the project will focus on studying the reproductive biology and growth of several species identified as being of high interest. This will enable culture techniques and optimal culture conditions to be established.
Finally, a preliminary trial of at-sea aquaculture will be conducted, to assess farming techniques in the local environment, which is more exposed than many areas where seaweed aquaculture is currently undertaken.
"Our aim is to develop techniques that will work in association with tuna and Yellowtail Kingfish farms which are located in the open seas of Spencer Gulf. This will be quite exciting as very little serious work has been done on the farming of seaweed in these regions before."
