In NSW it is legal to grow triploid pacific oysters as long as the growers in a particular growing area have an approved Review of Environmental Factors, (REF) for their growing area, approved by NSW Fisheries. A number of rivers in NSW have them approved and are growing these oysters.
What is a Triploid Pacific Oyster? These oysters have 3 sets of chromosomes and are sterile (they can’t breed). This is achieved by a couple of methods, both patented by “4C’s” in the USA and distributed by Shellfish Culture Hatchery in Tasmania. These oysters are guaranteed to be 100% sterile.
On some farms on the west coast of USA up to 50% of Pacific Oysters produced are this type. Many farms in Tasmania and South Australia use them also. Their main advantage is that they do not spawn and remain in good condition enabling growers to sell for longer periods of time hence improving farmers cashflow, and providing a good conditioned saleable oyster for a longer period of time.