The farm is off Waldegrave Island, Anxious Bay, near Elliston on the Eyre Peninsula and uses a new floating "reefs" technology. Currently the farm covers 60 hectares. The area is well known for producing large amounts of wild abalone. Water temperatues range from 14oC in winter to 18oC in summer, perfect for abalone growth and water flow is good providing well oxygenated seawater.
The system consists of 50m diameter floating rings or pontoons. The grid mooring system – which can accommodate 60 pontoons – is fixed to the seabed by large sand anchors.
Suspended below the pontoons are specially designed bases attached to nets. Each of these bases can hold over 132,000 abalone; the abalone are separated into 60 0baskets designed to maximise the surface area on which algae can grow.
Potential abalone predators, such as crabs, starfish, whelks (Orbita sp.) and sea hares are individually removed by divers who also clean and maintain the pontoons, cages and traysto ensure good water flow. The system uses no chemicals or artificial feeds.
Breeding stock for each year’s spawning is collected by experienced divers from the area around Elliston. The divers pick the healthiest animals with high meat to shell ratios and obvious significant growth.
The selected breeding stock are transported
to a quarantine holding facility at the hatchery and held there for 8-12 weeks prior to spawning where they are tested for diseases and are closely observed to ensure only the most highly conditioned stock is used for spawning.
The breeding stock is then spawned and eggs fertilised with sperm. Fertilised eggs hatch after 18 to 24 hours and become free-swimming larvae for two to four days before settling as juveniles on plastic plates where they graze on natural algae. Those plates are held in flowthrough
tanks inside greenhouses for increased temperature and light control. Water flowing into the nursery tanks is pumped directly from the ocean.
After transfer into the sea nursery cages there is an 8-12 month nursery period, during which the seed is monitored closely for disease, After this the abalone are transferred by divers to trays which have been in place for several months to allow algae to grow. The abalone can be harvested in less thn three years when they reach a length of 115 to 120mm and a weight of 203 to 225g. Divers harvest the adult abalone by hand and transport them in bags to the harvest vessel where they are sorted before sent onshore for processing.
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