Entrepreneurship & Home Business

Freshwater Pearl Farming

Posted by EPa in Fisheries

Combine a common freshwater mussel with an ingenious implantation technique and presto, a profitable industry is born. Its product: lovely, lustrious pearls for use in makeup and medicine.

Pearls, especially those with a good lustre, have been among man’s favorite gems since ancient times. Wearing pearls makes a person look radiant and more attractive. Is it any wonder then that men and women, young and old alike admire and cherish the pearl.

With the advance of scientific technology and the rising standard of living, pearls are now used in make-up and medicine. Demand has never been higher that it is today. The result is that pearls have become even more precious, with the price rising remarkably.

Freshwater mussels are found in abundance in the fish ponds of Taiwan. Previously, these mussels were of no commercial value and were, in fact, considered a nuisance by the fish farmers. Since recently, however, a new use has been found for these mussels in the culture of freshwater pearls. Smooth, bright and clear pears can be harvested after 2-3 years of cultivation using the fresh water mussels.

From Pest to Profit

The type of mussel used to culture pearls in Taiwan s found living in the soft mud at the bottom of most freshwater ponds. It is the benthic freshwater bivalve. Anodanta woodlana commonly called river clam or freshwater mussel.

In actual fact, freshwater mussels are really a nuisance to fish farmers when they invade their fish ponds. The adults compete with cultured fish for oxygen and freshwater plankton which comprises their food. Mussel larvae enter the bodies of the fish and attach themselves to the gills, causing young and weaker fish to die. So, as can be seen, freshwater clams are actually a scourge to fish farms.

Because the epithelium of the mantle margin of freshwater mussels secretes a substance called nacre, the utilization of technology to implant pieces of the epithelium in these clams can result in the production of pearls. Farmers have thus been able to take a pest and use it to create a profit-making industry.

Implantation Procedure

Pearls are made up of about 90% calcium carbonate, 4-7% conchiolin and 0.4-0.8% water. There are five characteristics to consider in determining a pearls value: texture, shape, color, size and lustre. If food technique is used during implantation, the resulting pearl will have good texture and shape. If the mussel is active, the implanted epithelial pieces are of good quality, and the mussel farm is well managed, the pearl will have superior color, size and lustre.

The mussels from which the epithelial implants will be taken are collected and put in buckets of clear water to flush them. For cutting the epithelial pieces from the mussels, a sharp razor blade is used. First, the adductor muscle is cut so that the shell may be easily opened. A pair of scissors is then used to cut strips of epithelial lining between the inhalant siphon and the adductor muscle. The epithelial strips are placed on a hard wooden board and the connective tissue is cleaned off the back of the strips. They are then cut into 3.0-4.0 mm long pieces. The thickness of the strips should be between 0.5-1.0 mm

Healthy mussels are selected and put into a vise assembly that