Harvesting cage and raceway farms
It is comparatively easy to harvest stocks from intensive culture systems, particularly tank and raceway farms. They can easily be drained partially or completely as required and the animals removed by dip nets or suitable mesh.
Harvesting from cage farms can be a little more complex, depending on the location and size of the cages. Except in the case of small cages, it will not be practical or advisable to lift them for removing the stock. In many cases it may be possible to tow the cages to the shore and harvest the stock using dip nets. Where this is not feasible, boats may have to be used. When the farm has central or peripheral walk-ways, it is easier to raise the cages and remove the animals. But even then, some producers prefer to use seines to gather the fish and, in large farms, pumps may be used to transfer the fish to the loading area. In salmonid cage farms in Norway, feeding is stopped for a period of about a week before harvesting. This is done to empty the alimentary canal, so as to prevent quick deterioration and also to ‘firm up’ the flesh. During harvest the fish are removed very carefully to avoid bruising the skin and meat.
Special care is taken to avoid undue stress to the fish during harvest, as meat quality is known to be affected by stress. Generally, the fish are transported by live-hauling boats or in plastic tanks installed in boats or trucks.