Oysters are saltwater bivalve molluscs that live in blackish habitats in the sea waters. They have an average lifespan of up to 20 years; however, outside water, they can live up to 2 days only. The average size of an oyster is 3 to 14 inches.
There are some species of oysters that are very hard while some are very irregular in shape. There are some oysters that produce special kind of pearls. These kinds of oysters are harvested in a special kind of environment in the seabeds to harvest the pearls. There are also other types of oysters which are edible oysters. They are different in specie from the ones that produce pearls.
History of Oysters
The history of oysters dates back to the time of Aristotle. They were first discovered by Aristotle from river banks near an Island called Lesbos. These oysters were then transplanted in another less populated area called Chios.
Oysters are cultured for more than a century now. They are set to mature themselves naturally or they are spread out on previously made oyster grounds on seabeds.
Today, many people use the same technique for gardening oysters as did their forefather in China, Japan, Greece, and Rome. The following is an account of major areas in the world where oysters were discovered and used.
Rome
One roman entrepreneurial devised a method by setting a net of twings around adult oysters to catch the small oysters whenever they were reproduced. He then moved the twings to another area for growing the oysters in spa locations in Rome.
Japan
In Japan, people used bamboos with leaves still attached. They also invented lantern nets that helped them to easily separate the oysters by size.
China
The Chinese however invented the most interesting thing. They developed an ear hanging for oysters and scallops which worked by punching a small hole in live oyster shell and then stringing them in a chain.
France
The French used a cement to attach baby oysters to wooden racks.
These were some of the methods used by the ancient people that are now gradually refined and expanded with time.
Oyster Harvesting Today
These days, commercial growers of oysters produce baby oysters in indoor hatcheries, which contain the right kind of conditions for adult oysters to produce the eggs. China is the greatest contributor in farmed sea food. It owns about 70% of the world’s global fish farming, including majority of oyster production.
The most sophisticated processes are raising their oysters in large metal racks that have a mechanical action to create the environment and stimulation of rough sea. Other methods include introducing a warmer temperature so that the hatching process can be accelerated.
Some other factors such as climate change and pollutants in the sea can greatly affect the breeding process. Due to these factors, the oyster shells are not fully formed, which make it harder for baby oysters to build their calcium carbonate rich shells.
