Tool to improve ocean aquaculture

A new automated tool that provides support for sea cage aquaculture managers in making crucial decisions about locating their sites and determining the number of fish that can be sustainably farmed is now available.

A project undertaken by the Australian Institute of Marine Science (AIMS) in collaboration with the Indonesian Ministry of Marine Affairs and Fisheries, and funded by the Australian Aid Program through the Australian Centre for International Agriculture Research (ACIAR), has developed a user-friendly decision support tool available on CD and the Internet.

CADS_TOOL (Cage Aquaculture Decision Support tool) is immediately useful to finfish aquaculture in South East Asia but is equally useful in tropical Australia, according to AIMS researcher Dr David McKinnon.

Australia does not yet have a lot of tropical sea cage fish farming, with only two such farms producing barramundi in northern Australia, including one near Cardwell. The major growth area for tropical sea cage aquaculture is South East Asia.

“Indonesia in particular has a huge need for management tools in aquaculture development,” Dr McKinnon said.

“It is the largest aquaculture producer in South East Asia and the industry nearly trebled in size between 1995 and 2000,” he said.

Indonesian aquaculture mostly produces high value finfish such as coral trout, which fetch around $90 per kilogram live on the Hong Kong wholesale market.

To address the huge growth in South East Asian aquaculture, the AIMS/ACIAR project employed physicist Dr Halmar Halide to develop a simple yet robust tool that any sea cage aquaculture manager could access and use.

Dr Halide, who was on secondment to the project for two and a half years, returned recently to the Physics Department at Hasanuddin University in Makassar, South Sulawesi.

The tool that he devised assists with site classification and selection, and determines how many fish can be held at a particular location. It is planned to also make the package available on CD from AIMS.

One of the major challenges associated with growing fish in sea cages is finding the right place to put the cages. Site selection is the biggest factor in determining the commercial viability of a sea cage aquaculture operation, according to Dr McKinnon.

Finding a location that has the optimum water quality, water temperature, oxygen, light and nutrient levels, that is close to where farm workers live and to markets for the fish involves a complex range of decisions. CADS_TOOL will simplify the process for many sea cage aquaculture managers.

The tool allows managers to classify a site, select the best site from several alternatives, calculate its sustainable holding density and perform a basic economic appraisal.

“We believe that CADS_TOOL will greatly improve decision making by sea cage aquaculture managers,” Dr McKinnon said. “In a rapidly expanding industry, this will be a major factor in ensuring both environmental and economic sustainability.”