10 Harvesting and packaging

The production cycle ends with fish harvesting once the fish have reached the desired. market size and can be sold.

The regular availability and steady supply of good-quality fish is one of the main factors that distinguish aquaculture from wild-stock fisheries. This is an advantage from a commercial point of view, but at the same time it also means specific responsibilities for producers. Producers may even lock in contractual commitments with their customers as to the product's supply on prearranged days and in precise quantities.
Some harvesting techniques are described in detail below. The decision on which technique depends on the operator's experience, as well as on other factors such as the type of cages, sea conditions and weather conditions at the time of harvesting, the quantity of fish to be harvested, the target species, and the fish density inside the cage. Harvesting is a key operation that requires the use of trained and skilled surface operators and divers. The quantities of fish to be harvested from each cage must be planned ahead of time. A technical briefing is useful for coordinating the harvesting crew.

The common problems that may be encountered during harvesting operations include harvesting the wrong number of fish, damaging the fish and failing to chill the harvested fish properly. These problems are critical, and every care should be exercised to avoid them:

Harvesting too few fish

If the first attempt does not provide sufficient fish to meet the harvest orders, then further attempts must be made. Repeated harvest net sweeps can be difficult as, in some cases, the fishing net may need to be prepared on land, there may be insufficient scuba bottles, or the divers can be approaching their maximum allowable bottom- times. Moreover, repeated harvest net sweeps can stress the fish inside the cage, with consequent risks of disease or lack of appetite.

Harvesting too many fish

If more than the planned quantity of fish is caught, there may be insufficient bins and ice, and, consequently, the cold chain might not be maintained.
Alternatively, the release of excess fish once they have been caught in the harvest seine net may result in stress, scarring or mortalities.
Damage to harvested fish or to the fish remaining in the cage
This may result in an economic loss owing to the decreased value of the harvested fish or increased mortality in the cage stock.
Cold chain interruption during harvesting or in packing and processing
This can lead to unsellable product because food safety and quality require that the fish be quickly chilled and then remain cold throughout the processing stages.