Shellfish culture and productivity of our rearing places

Abstract

       Besides fishing in the open sea and thereby risking the catch or the fishing near the coast with limited possibilities, our Fisheries could increase the exploi­tation of the production areas, i. e. the spawning places and rearing places of fishes, crabs and shellfishes. In such a way it would be possible to supply the market with a definite quantity of quality products.

       For the realisation of this programme it is necessary to examine the suita­bility of every single activity mentioned above.

       In this paper the problem of rational oysterspat collecting and the suitability and increase of production in our shellfish rearing places is considered. For the solution of these problems the assistance of scientific research is necessary.

       It is essential for each rearing place.

1. to examine the fertility of a determined volume of sea water,
2. to control the hydrographical data (To, S, O₂, pH, transparency) and currents occurring in the sea water,
3. to determine the origin of the sea bottom, damages inflicted by competi­tors, enemies, diseases and parasites,
4. to understand the sexual cycle of the shellfish,
5. to practice plankton control in the rearing zone,
6. to modernize the rearing methods by giving up the artisan methods and by accepting the industrial ones, by applying modem auxiliary materials and mechanisation (automatic machines),
7. to apply methods of artificial enrichment of the sea water by means of nutritive salts (fertilization) which have already been examined (Buljan 1957, Morović 1958, and Pucher-Petković 1960).