Marine mammals (whales and seals) can provide no increase in the current 

 catch level, and for the next few years, hunting of these mammals will 

 continue to decrease. 



1.4 Basic Trends in Further Development of Ocean Fishing 



The study of the processes of biological productivity occurring in 

 relatively small seas (the Azov Sea, Caspian Sea, Black Sea, Baltic Sea 

 and North Sea) have shown that the total production of fish (expressed 

 as weight) is usually 50-100 times less than the annual production of 

 invertebrate, plankton and benthos. The production of the most valuable 

 species from the standpoint of food--the tuna, marlin, mackerel, 

 sail fish, etc., as well as the sharks--which occupy the fourth, fifth or 

 even sixth trophic levels, are hundreds or thousands of times less than 

 the production of phytophagous and planktonophagous fish. Thus, based 

 on the primary production of the ocean, as a result of the tremendous 

 losses in the intermediate links of the food chain, only a relatively 

 small quantity of fish production needed for man is created. This type 

 of loss occurs, in particular, due to the great number of "food 

 deadends." For example, in the North Sea, over 90% of all of the edible 

 animals are consumed without any benefit from the standpoint of 

 commercially valuable animals. 



The predominant portion (75%) of Black Sea zooplankton consists of 

 predators--Sagittae, Ctenophora, Noctiluca, which are almost never used 

 as food by fish, but they consume tremendous quantities of edible 

 zooplankton. Losses of this kind are found in the other regions of the 

 ocean, as well. At best, 30% of the total biomass of the zoobenthos 

 from the continental shelf of the World Ocean may be used as food by 

 fish and other commercial species, while the remainder are terminal 

 links in food chains. Unless a transition is made to commercial 

 utilization of species at lower trophic levels and significant 

 adjustments are made to the biologic production processes, we cannot 

 expect any significant increase in the world catch. One means for 

 increasing the volume of oceanic biologic resources usable by man might 

 be the organization of fishing for the massive representatives of 

 zooplankton. However, in addition to the undoubtable successes, the 

 first steps in this direction will also involve many difficulties. 



Various means and methods of expediently changing individual links 

 in the oceanic processes of biologic production, making them yield 

 higher results from the point of view of man, could be of great 

 significance. Various forms of biologic reclamation, acclimatization 

 and transplantation of commercial and feed organisms, the creation of 

 new hybrid forms for stocking of regions with a good food base, but 

 environmental conditions which are unfavorable for the ordinary species, 

 incubation and raising of larvae and fry of certain commercial fish, to 

 be subsequently released in the sea, the creation of "underwater 

 gardens" and marine fish farms, alteration of the oceanographic modes of 

 individual regions in the seas and oceans by means of hydraulic 

 structures, and many other methods should be studied and, possibly, may 

 be found to be effective for these purposes. 



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