South Australia’s aquaculture industry is diverse, with major established sectors including Southern Bluefin Tuna, Yellowtail Kingfish, Oysters, Mussels, Abalone, freshwater finfish and crayfish. Existing and new sectors are efficiently and effectively regulated under dedicated aquaculture legislation, the Aquaculture Act 2001 (the Act), the objectives of which include Ecologically Sustainable Development (ESD). A rapidly emerging sector in the aquaculture industry is seaweed (Nayar et al., 2015). Potential benefits of the sector include nutrient offset, IMTA, carbon mitigation and a range of product opportunities in markets for human consumption, pharmaceuticals, bioactive, nutraceuticals, cosmeceuticals, bioplastics, fertilisers, livestock feed ingredients and bioenergy (Nayar and Froese 2013; Nayar and Bott 2014; Hossain et al., 2022).

IMTA has been defined as “the integrated culturing of fed species, such as finfish, inorganic extractive species such as seaweeds, and organic extractive species such as suspension and deposit-feeders,” often for the intent of improving the sustainability of an aquaculture system, maximizing the use of a system and space, and increasing profits through commercial production of additional species (Chopin et al., 2012; Ahmed and Glaser, 2016; Troell et al., 2009 In Alleway et al 2023). Within a South Australian statutory aquaculture zone policy context, IMTA has previously been defined as “an aquaculture farming system in which 2 or more species are farmed in close proximity such that waste generated from 1 species is recycled as feed for another species” (Aquaculture (Zones – Eastern Spencer Gulf) Policy 2005).

In South Australia, the LEP aquaculture zone is the largest, in terms of value and production, and most diverse aquaculture zone, and can be considered a regional IMTA system. This project will use the recently reviewed LEP aquaculture zone policy as a case study to document how empirical data on the growth and nutrient uptake between IMTA species can be used to (i) quantify transfer efficiencies within open water IMTA systems and (ii) develop models of increasing complexity, to assess the performance of IMTA and support marine spatial planning and IMTA policy development at the regional scale. The overreaching goal is to develop a framework to inform marine spatial planning for sea-based aquaculture to optimise the economic success and product diversity while minimising impacts on the environment and other users of the marine estate.

Alignment to strategic priorities:
This project aligns with a number of national strategies, including (but not limited to): Ocean Decade Australia (healthy marine ecosystems; sustainable ocean economy), the National Aquaculture Strategy (priority 1: regulatory framework, priority 2: Research, development and extension, priority 3: market access and priority and priority 5 Public perception), the Australian Seaweed Industry Blueprint, the Seafood Industry Australia – Aquaculture Advisory Committee Action Plan, the Blue Economy CRC and FRDC’s strategic priorities (e.g. R&D Plan 2020-2025: 1 Growth for enduring prosperity; 2. Best practices in production systems; 5. Community trust, respect and value).

Relevant South Australian (SA) strategies include the Blue Carbon Strategy for SA, the SA Government Climate Change Actions, Carbon Farming Roadmap for SA, the SA AgTech Strategic Plan (priority 1: Networking and collaboration, priority 2: Demonstration and understanding and priority 7: Government leadership), PIRSA Strategic Plan (priority 1: Stimulate value growth and priority 3: sustain the resource) and the SARDI Strategic Plan (pillar1: Improved productivity in a changing climate, pillar 3: Sustainable management of natural resources that underpin primary production, pillar 4: increase value of exported products, pillar 5: new partnerships and business models and pillar 6: Impact through adoption).