Ocean Grown Abalone
Ocean Grown Abalone (OGA) found a novel use for concrete when creating a world-first abalone ranch in Augusta Western Australia. OGA used a highly fluid, high-strength concrete mix to create ABITATs - specifically designed artificial abalone reefs - which are made in-house by the OGA team.
ABITATs are lowered into the pristine ocean of Flinders Bay where, according to OGA Managing Director Brad Adams, “the ranches are self-sustaining and the abalone nurture and feed from the ocean until they are ready for harvest.” This environment results in abalone almost identical to their wild caught counterparts.
The benefits of ocean ranching, rather than land-based aquaculture, are substantial. OGA can save costs in infrastructure, power and feed by using the ABITAT system. They are also spared the difficulty of sourcing large areas of in demand coastal land.
Strength and integrity in highly corrosive environments
ABITATs are created by filling custom made forms with a highly fluid, high-strength concrete mix. As steel reinforcement is not suitable for underwater applications, Radmix Polyfibres are added. These polyfibres are designed to give the benefit of extra strength and integrity in highly corrosive environments without the risk of cracking or rust. The OGA reef construction yard is capable of producing up to 70 ABITATs per week.
OGA’s ranches are built in areas that have suitable climate and ecosystems for abalone, but lack an appropriate reef structure. ABITATs are positioned underwater by divers and then left for 6-8 weeks to condition. Once algae has colonised on the surfaces, the ABITATs are seeded with hatchery reared greenlip juvenile abalone from partner company 888 Hatchery.
Greenlip abalone, sometimes called smooth Australian abalone, is a type of sea snail, or marine gastropod. Their meat is sought after as a delicacy, particularly in Asian markets, and live abalone can be sold for up to $100 per kilo. Abalone shells are unique for their shallow, ear-like shape and colourful nacre (mother-of-pearl) interior which can range from a pale iridescent cream to deep turquoise, purple, and blue.