Benthic biocoenoses of the Adriatic as new sources of food and various raw materials,with special consideration for sponges and corals

Abstract

       From 1947 to 1971 the Yugoslav catch of edible species was tventy to forty thousand tons per year. The fishes represent the main part of the catch (look at the upper part of the graph 1); conversely, the total catch of all other edible species does not reach either one thousand ton per year.

        Inside the fish group, the quantity of the pelagic fish (blue fish) is remarkably larger than the quantity of the bottom fish (Tables 1-4; for the period from 1947 to 1960 the catch of the bottom bony fishes - Teleostea - is separated from the catch of cartilaginous fishes - Selachia - and for the period from 1961 to 1971 the catch of both groups are given together). Although the bottom fish catch is smaller than the pelagic fish catch, and is not favourable for manufacturing, the bottom fishes are nevertheless the important factor in the nourishment of the popu­lation, especially in the coastal parts of Yougoslavia. Among the other edible spe­cies, the catch of cephalopods stands out with constant quantity of about 400 tons per year in the period from 1947 to 1954, and in the period from 1955 to 1971 with about 500-600 tons per year.

        Among the crabs, the Norway lobster (Nephrops norvegicus/ L/) is dominant in some areas, and these are areas of the biocoenosis of muddy bottoms »Nephrops norvegicus - Thenea muricata (Bowerbank)«. The north Adriatic canals give about  80%, and the open Central Adriatic about 20% of Norway lobster catch per year. The catch of the spider crab (Maia squinado Herbst) refers mainly to the Coast of Istria and northern part of Croatia; the catches of crawfish Palinurus vulgaris Latr.) and European lobster (Homarus vulgaris H. Milne - Edwards) are considerably smaller than the catch of the mentioned crabs, and refer mainly to the Central Adriatic.

        The data on shellfish catch show the largest fluctuations, because they depend upon the artificial conditions, and our fishery has not paid much attention to it yet. From 1967, the shellfish catch is constantly about 400 tons per year, shownig an increase in 1969.

       The sponges (in the period from 1949 to 1964, approximately 5000 kg per year) and the corals (in the period from 1952 to 1955 about 300 kg per year), altough they are in smaller quantity than fishes, molluscs and crabs, could nevertheless be an important factor in our economy.