The term oyster covers a number of groups of marine bivalve molluscs which grow in the sea. They live only in salted water (containing 30 to 32 grams of salt per liter (g/l) or less) and are found in all seas.
The oysters are very popular in terms of gastronomy and they are said to have aphrodisiac properties. Most of the annual production is sold during the holidays season.
Culture
The culture of oysters is called oyster-farming and is doned on the coasts.
Four breeding methods are known:
- suspended on tables (in the Mediterranean sea)
- in deepwater
- on the ground
- off bottom
Bottom culture of Pacific oysters
This more traditional farming (mostly used for oysters) is practiced in deep water, it is to disperse the oysters on the ground (sand or mud) on farms that do not find themselves at low tide and harvest oysters with a dredge.
Big advantage: oysters will grow better because constantly in the water, they breathe and eat more .
The default, and significant for oyster-farmers, is that oysters are too exposed to predators like the royal breams or stripes. They are not protected by pockets.
These fishes can crumble oyster shells and devour an entire breeding season in a few weeks.
Off bottom culture of oysters
The most common method of farming is practiced in shallow water uncovered at low tide: the foreshore.
It is much more modern and was born in the 1970s. It is to have oysters pockets on iron tables 80 cm high, with 4 hooks of different model, different diameters and colors.
Tides allow work in dry or semi-dry conditions in these parks.
The advantage is that the bags will protect the oysters from predators and will be easier to work with. The oysters bags must be split every 6 months, as the more oysters are packed, the less they will grow.
This is why at each age is a size oyster mesh pockets for easy insertion of the currents in the pockets that provide food and oxygen to the oysters.
This operation also allows to change oysters from one park to another according to their size and their growth. It will also need to turn the oysters bags every month of the summer to well spread them in their pocket, and at the same time to remove the algae that grow below the pockets and spoil by their weight.
Adult oysters eat plankton (phytoplankton and zooplankton) which are small organisms that follow the currents. Oysters filter an average of 10 liters of sea water per hour. |