Whiting stocks in the eastern Spencer Gulf must not be affected by what the South Australian Government hopes will be a “game-changing industry” in seaweed farming, locals have warned.
- The SA Government proposes commercial seaweed farms in Hardwicke Bay
- Seaweed can be used as a livestock supplement to reduce methane emissions
- The Australian Seaweed Institute releases a $1.5 billion industry blueprint
The State Government wants to alter a 60-hectare aquaculture zone in Hardwicke Bay to allow seaweed cultivation — kickstarting a $140-million industry state-wide that will create livestock supplements that reduce greenhouse emissions from cattle.
The aquaculture zone includes three different lots about six kilometres offshore from the Hardwicke Bay and Point Turton townships and currently only allows for mollusc farming.
Hardwicke Bay Progression Association president Ashley Gordon said the draft documents released for consultation were a little “short on environmental impacts”.
“Clearly, we don’t want the fishing grounds damaged or harmed in any way,” he said.
“Having to drive your boat around a 20-hectare area is not a big deal — it’s a two-minute diversion — but what people here want to know is if it will wreck the whiting grounds.
“It’s as simple as that.”
At the same time, however, Mr Gordon said anything that brought jobs to the region was welcomed, as was the potential for seaweed-based livestock supplements to reduce emissions.
Seaweed to reduce emissions
Australian Seaweed Institute chief executive officer Jo Kelly said seaweed infrastructure was similar to oyster or mussel farms, with the algae often cultivated on long lines attached to buoys at the water’s surface.
She said Asparagopsis variety of seaweed was native to SA waters and, when fed to cattle in small amounts as a supplement, could reduce their methane emissions by “over 99 per cent in some cases”.
“There hasn’t been a lot of research on the ecosystem impact of these things, but we do know that it improves water quality, reduces the likelihood of outbreaks of blue green algae or toxic algae type blooms,” Ms Kelly said.
“It also provides habitats for fisheries resources.”
The CSIRO has utilised Asparagopsis to develop a livestock supplement called FutureFeed, which it said reduced methane from livestock burps and farts by more than 80 per cent.
It worked by significantly diminishing the microbes in a cow’s stomach that caused it to pass air.
Seaweed farming to coexist
The State Government said tenures would be allocated through a competitive process and any license applicant would have to farm varieties and develop infrastructure types best suited to the zone.
Primary Industries and Regional Development Minister David Basham said algae and shellfish farming had been recommended worldwide as a way to “minimise the potential negative effects of nutrient inputs from other activities”.
“Aquaculture zones have been in place at Hardwicke Bay for 15 years and there have been no issues with fishing in that time,” he said.
No hectares are currently allocated to any aquaculture licensee in the Hardwicke Bay area, but locals said a small attempt was made to farm molluscs at the northern end of the bay near Port Victoria some time ago.
SA with 1,500 species
The Australian Seaweed Institute recently released a $1.5 billion blueprint for a national seaweed industry, outlining a need for more farms and regional processing plants.
The institute found SA to have Australia’s largest area leased to seaweed aquaculture at 1,220 hectares, with Tasmania second at 301ha.
“But Asparagopsis is a really big thrust for the industry, which is the stuff that will be sent to cattle, and exported to the likes of California where they have really stringent emissions targets in place.
Mr Basham said SA had one of the highest levels of diversity for seaweed worldwide, with more than 1,500 species known to occur.
“[Global aquaculture advocates] CH4 has estimated that if commercial production systems and processes can be established, seaweed production in the state could be worth $140 million a year within three years.”
He said that processing the seaweed could add a further $250 million to the state economy and support 1,200 jobs.
Public consultation on the proposed changes to the eastern Spencer Gulf aquaculture zones closes on October 23.