I thought it might be interesting to show one method of supplying juvenile oysters to our farm. During the autumn wild oysters spawn up and down the NSW coast when the natural environmental triggers occur. These are water temperature, a drop in salinity caused by rainfall and often very high tides that occur on the full moon. Oyster farmers use this natural phenomena and place catching material on special leases where this larvae is concentrated and on an average year get a good settlement rate. In our case we use the Moruya River and Narooma.
At this time of the year farmers are moving this catching material back to their growing leases for on growing and finishing. At present we are moving plastic slats back to Narooma to strip the seed. We trailer a punt to Moruya and bring back approximately 1000 slats a load which were placed on a rack in the water, at the correct height and on a frame holding a little over 100 slats.
This year has been a good year with many 100,000’s of oysters settling on our catching material. We pull the frames a part flex the slats and the spat falls into a tub. We water grade the spat and divide it into sizes that will not fall through our different container mesh sizes. At this stage it is important to put the right volume in each container. It is important at this stage to get the oyster shell shaped ( deep and cuppy) as it will hold that all its life and the meat condition will follow that shape. In two years time we aim to have marketable stock.
In addition to this we use serrated French tubes ( 1.2 metres in length) to catch wild oyster spat and a large quantity of hatchery grown oysters.