Seaweed aquaculture is well established in Asia and is expanding in western countries, but previously there have been no offshore ventures in Australia.
“We import around about $20 million in seaweed products a year, so there’s quite a large market that’s there,” said Kathryn Wiltshire, Aquatic Sciences Research Officer at the South Australian Research and Development Institute (SARDI).
“Obviously we can fill that local market and there’s also the potential we may be able to export our species, because we’ve got a lot of unique species that don’t occur anywhere else in the world.”
Four native species are being grown as part of the 12 month sea trial being held off Eyre Peninsula.
“It’s actually been quite a long process to get to this point, we’ve got about 2000 species that are native in South Australia,” said Ms Wiltshire.
“There’s relatively little known about seaweed species, even some of the common ones, their biology hasn’t been very thoroughly researched.”
Literature reviews and laboratory studies were required to determine which native species could be suitable for farming.
“For example ones that are really rare are obviously not going to be suitable, ones that are very small, ones that don’t grow in similar environments.
“We don’t want to introduce something, there’s the potential then it could become a pest species, or it may simply not be suitable for the environment we have.”
Of the selected varieties, plants were collected from the wild, transplanted onto ropes and submerged up to five metres under the ocean’s surface near Port Lincoln- the shallow conditions allowing sufficient light absorption.
Additionally, these ropes have been placed near fish farms, determining whether the wastes from these farms can be used to boost the seaweed’s growth.
Referred to as Intergrative Multi-Trophic Aqaculture, Ms Wiltshire aims to determine whether this can be applied to further the future industry’s environment sustainability.
“The seaweeds are taking up nutrients from the fish, so that can reduce the environmental footprint of the fish aquaculture, and it is actually acting as a fertiliser for the seaweed to make them grow better.”
If the plant’s commercial viability is proved, there will be a variety of potential markets and uses for the product.
“It will come down to exactly which species is most suitable as to what those final markets are,” Ms Wiltshire said.
“We’re looking at ones probably not so much as food directly, but their extracts may be used in food products.
“A lot of them are used as gelling agents in a lot of industrial products, such as aerosols and adhesives. They could be also used in fertiliser and as stock and pet foods, and a myriad of other uses.”
Photo caption: Farmed seaweed could be used in a variety of products, from adhesives to fertilisers and food products ()
View original article at: Could seaweed farming be Australia’s next aquaculture industry?