Until now one of the main inhibitions on the development of shellfish farming has been an almost complete lack of knowledge of techniques which are well established elsewhere in Europe. The Italian pergolari method of mussel farming is the only one with which there is familiarity in Greece. Spanish rope culture of mussels and French techniques for collecting and growing-on oysters are unknown, though a small quantity of Yugoslav collectors and hanging oyster baskets have been purchased by the Ministry of Agriculture for trials in Amvrakikos Gulf.
Developments in Manila clam cultivation methods in France, Spain and Italy are also unknown, though these will need adaptation to Greek conditions, where the available sites are quite different from in those countries.
This is not a constraint for mussel cultivation, where there is room for expansion in existing areas, especially Themaikos Gulf. Long line culture opens up wide areas for expansion in more offshore sites, with N. Evoikos Gulf and Maliakos Gulf offering excellent sites. Pole culture can also be undertaken in Maliakos.
Oyster culture will remain localized in Thermaikos Gulf and Maliakos Gulf, but in both there is much room for cultivation. The new Thessaloniki sewage discharge scheme may reduce the area of suitable water in that region.
Potential palourde cultivation sites are very limited. Inter-tidal areas around Alexandropoulis, Lagos and Maliakos Gulf should be suitable. In some superficially attractive areas, native populations of palourde indicate growth rates too slow to be of commercial potential (e.g., Kyparissi). Ponds could be excavated for palourde or Manila clam farming where a good tidal exchange can be arranged (e.g., near Alexandropoulis). The same applies to ponds for penaeid culture. Managed ponds could be constructed near the lagoons where P. kerathurus fisheries exist. There is little area available for extensive culture, as most suitable lagoons already have well-established trap fisheries which would conflict with the management requirements for cultivation.
This presents no real problem for mussels or oysters in Greece, though spat collection techniques need to be established. Palourde cultivation can only be based on known available seed, which is limited to Alexandropoulis. Manila clams have not yet been imported, and the developing industry will be obliged to buy seed from western European hatcheries. Without this there is no prospect of developing palourde aquaculture.
If penaeid farming is to become established in Greece, it will require a hatchery using broodstock maturation techniques. Current interest in penaeid hatcheries, both by private industry and the Ministry of Agriculture, could, if realized, overtake the availability of suitable on-growing sites.
This is covered by another report in this study (MacPherson). In the north of the country most shellfish activity is carried out by fishermen's cooperatives. These are the best equipped to expand mollusc culture through their knowledge of existing fisheries and markets. Smaller, individual growers, such as those around Salamina, face additional difficulties, especially in relation to obtaining planning permission.
A national trade association would help in promoting cultivated shellfish and in the internal policing of quality control standards.
There is a misinformed but widely held view in Greece that shellfish farms, especially those for mussels, are sources of pollution to the marine environment. This will be difficult to displace because it is frequently used by interests wishing to prevent shellfish farming becoming established in their area. It can only be countered by good presentation of the true facts. Where this involves public discussion, it should be used to dissociate shellfish from pollution in general.
The consultant provided a letter of support to the Attica area office of the Ministry of Agriculture, countering the idea that bivalve cultivation causes pollution.
The known export markets for oysters, palourde and shrimp all face supply shortage and are not constraints. Better quality of oysters through cultivation, and better preparation prior to long distance transport (e.g., by ‘hardening’, exposure to air a few hours in the days prior to shipment) could achieve better prices.
In the case of mussels, the small home market could soon be exceeded. Export opportunities exist, especially in France, provided large-scale production reduces costs. The introduction of mechanized Spanish rope culture could help achieve this. The size favoured in France (45 mm) could be grown in 6 months in Greece.
The need for public confidence in depuration as a pre-requisite to expanding home markets has already been discussed (4.2). Export markets are sensitive to disruption by public health scares, and the Spanish mussel industry has suffered from this. The export of unpurified palourde from sites such as the one on the east side of Salamina has great potential to damage the reputation of Greek shellfish at home and abroad.
Product labelling, including the identification of the producer and packing date, are essential to both public health control and marketing. The practice is well established for shellfish in Greece. Labelling could give prominence to the fact that the shellfish are cultivated and hence subject to public health controls.
The home market for molluscan shellfish could be expanded by directing sales effort at the considerable tourist hotel trade.
