Spat to Slurp Series
Part II: Farming
Typically, when most people think of farming, they may picture vast rural landscapes of various crops. Oyster farming, a type of aquaculture, may not immediately come to mind, but it is a fascinating practice that dates back thousands of years. It is understood that the ancient Romans practiced oyster farming until it was forced to an end by the barbarian invasions that brought the demise of the empire. Fortunately for us, oyster farmers around the world have continued and improved their craft until this very day.
Overview
Oyster farming utilizes the natural oyster life cycle we talked about in Part I of this series. As mentioned there, oyster reproduction and growth rely on salinity and temperature of the water, as well as nutrients and other elements. Oyster farmers create the optimal conditions for oysters to grow and reproduce more efficiently, whether in natural or artificial systems. This involves raising and lower water temperature to mimic seasonality and altering salinity, which can encourage oysters to reproduce and mature at faster rates. While there are many methods and techniques, there are general principles that hold across the board.
Oyster farmers will place a batch of mature oysters, or broodstock, in a system and alter the conditions to encourage reproduction. These conditions involve carefully treated water, varying water temperature to promote spawning, and other factors depending on the technique utilized. After reproduction, the larvae are placed in carefully prepared containers and tanks that are tailored for efficient larvae growth. Tanks are usually filled with relatively warm seawater for faster growth and algae that larvae filter through their gills for feed. Also, they should be routinely cleaned to avoid complications with other organisms. When the larvae reach the stage of developing a foot, they are placed in another system where they can settle on a hard surface, or cultch, to grow. Of course, as we talked about before, this is when they become “spats.”
Harvesting Techniques
Overall, the process described above leverages an existing phenomenon, while taking measures to expedite and harness it. There are a few techniques when it comes to cultivation.
Farmers can place the resulting spats over naturally forming oyster beds and develop, then collect them later using methods, such as dredging. Dredging is the process of extracting material from a bed of an area of water – boats or other devices can deliver this method. This is known as “bottom culturing.”
Farmers can also place the newly developed spats in cages, bags, or other containers and held near the bottom of the sea. When oysters reach maturity, the containers can be extracted for collection. This is typically known as “off-bottom culturing,” which allows for more protection and control over the developing oysters.
Additionally, farmers can place the spats on a prepared clutch within an artificial tank. The tank can be filled with water specifically treated for efficient oyster growth – specific temperature and salinity alterations.
When oysters reach maturity, they are collected for distribution, the next stage in the process. However, some oysters may not have developed enough for the market, so they are introduced back into the system until their day comes.
Throughout these various stages, oyster farming is highly labor intensive. Additionally, farmers depend on market demand and high-volume sales of their oysters for business sustainability. Check out the Oyster XO Shop to support these men and women and their efforts while continuing to enjoy your favorite delicacy of the sea.
Impact
Oyster farming is considered nonthreatening and environmentally favorable. This aquaculture practice encourages and delivers oyster population growth, which has positive effects on oceanic ecosystems. Therefore, not only are oyster farmers responsible for the production stages of the oyster supply chain, they contribute to positive environmental efforts with their work. In the next part of this series, we will discuss restoration projects and the organizations involved.