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Farming Pearl Oysters

The farming of the silver lipped pearl oyster for pearls and other products (Mother Of Pearl shells and pearl meat) is Australia's largest aquaculture sector. Western Australia is the largest pearl producer, followed by the Northern Territory, with the WA industry producing around $200 million in export income in the eraly 2000's. The Aquaculture Council of Western Australia has estimated that the value of Australian pearl production may reach $500 million by 2010.

Other species farmed on a much smaller scale include the black-lipped pearl oyster, the shark bay pearl oyster, the Winged Oyster and the akoya pearl oyster. The silver lipped peari is the largest pearl oyster found in the world.

Australian pearls are exported to over thirty countries with Hong Kong, the United States, the United Kingdom, Switzerland and Japan being the largest buyers.

How are cultured pearls produced?

For further information: www.costellos.com.au/pearls/cultivation.html

The first step is for divers to collect young oysters from the sea floor floor at depths of seven to 20 metres. The divers work from a pearl boat which also stores the pearl oysters collected. These oysters are then counted, cleaned and weighed, before they are placed in metal frames between layers of nylon netting. The oysters are then transported in a saltwater tank to a holding area, where the frames are attached to the sea floor to allow them to recover from the stress of their capture.

In a few months the panels are lifted back onto a pearl boat where the oysters are opened and
seeded by a technician.

A tiny piece of mantle cut from another oyster and a nucleus are placed into a pearl oyster by making a tiny cut into the reproductive organ of an oyster. The nucleus,a small bead of oyster shell, is placed into this tiny hole and the a tiny piece of mantle tissue is then placed behind it.

The best material to use for this is the shell of the North American mussel because it is least likely to be rejected by the oyster.This graft will form a pearl sac and calcium carbonate will be deposited, layer by layer like onionskins, into this pocket around the nucleus to form the pearl.

After being seeded, the oysters are returned to the holding area in their panels for further recovery. After several months later the shells are transported, sometimes up to 2,000 nautical miles away, to remote farming bases.

At the farms, the panels holding the oyster shells are hung on long lines supported by buoys. They are looked after every day day by farm workers who carry out the intensive for up to two years before they are harvested. Each oyster can now be seeded at least three times during its productive life producing a pearl every two years.