SA oyster industry adapting to drought

Drought is mostly associated with land-based farming, but primary producers making a living from the ocean are also feeling the impacts of drought. 

Recently our South Australian Regional Recovery Officers were in the coastal town of Cowell, near Franklin Harbour, to meet with oyster farmers and find out how drought has impacted the local oyster industry.

The team also took a tour of the Eyre Shellfish oyster hatchery and processing plant to learn how oysters are produced.

“Many people have a vision of drought only impacting pastoral country and wide open spaces, but drought impacts many regions and a wide range of industries, including aquaculture,” said Justine Major, North SA RRO.   

“In South Australia parts of the coastline are in drought, so the dust that gets picked up by the wind gets blown straight into the ocean.”

“These dust particles have led to several poor seasons for oyster farmers, as the fine particles reduce the fertilisation process of oyster larvae.”

Baby oysters - which look like grains of sand and are known as ‘spat’ -  are delicate and easily susceptible to changes in the environment.

But it’s not just the dust that’s a problem for fishers and seafood producers in Franklin Harbour. Drought has also caused an increase in salinity levels in the harbour due to an absence of rain.  When the salinity gets too high, oysters and other marine species do not grow properly. 

“In normal circumstances, water from the harbour is pumped to the hatchery and mixed with algae to provide the ideal breeding environment required for the oysters,” Justine said.

“To cope with the drought, oyster farmers have had to build large water tanks in order to reduce salinity levels by adding fresh water to the sea water.“

Once the spat grow to 2mm they are then transferred to a nursery where they are grown to 10mm before being placed in frames for transport to the oyster farms in the sea. 

It can take between 12 months and 4 years for an oyster to grow to a marketable size, depending on the species and growing area. The oysters are harvested twice a week and sold across Australia.

“It was great to be down here and learning how this wonderful seafood is produced,” Justine said.

“This visit was to highlight that coastal areas can also be drought effected, and we need to make sure we’re looking out for all our primary producers, wherever they farm.”

The Drought and Flood Agency wishes to thank the staff at Eyre Shellfish and Simon and Meagan Turner from Turner’s Oysters for giving us the opportunity to visit.