seasonal processes. The larvae of the various species of animals settle 

 at different temperatures, which defines the sequence of appearance of 

 the various species in the composition of the fouling assemblages and 

 determines the succession of these biocenoses (Zevina, 1972). 



Thus, for the fouling communities, which develop in the internal 

 seas and littoral oceanic regions, a small number of species 

 (oligomyctic nature), a high biomass and the seasonal changes in the 

 process of formation are peculiar. 



Studies of fouling processes in the oceanic waters are only 

 beginning. The formation of large masses of fouling in the open ocean 

 is limited by the lack of a stable substrate. Although organisms which 

 are not inhabitants of the littoral regions are always found on the 

 hulls of ships which follow the transoceanic routes, the oceanic forms 

 alone never develop on ship hulls. We can make judgments concerning the 

 composition of fouling associations in various regions of the open ocean 

 at the present time by studying driftwood. Materials collected from the 

 northwest Pacific (Turpaeva et al . , 1976) show that oceanic fouling 

 communities are also characteristically oligomyctic, with a high biomass 

 and seasonal alteration of composition, related not only to seasonal 

 changes in the presence of pelagic larvae in the plankton, but also to 

 changes in the overall flow of the currents. 



In spite of the seasonal changes in the composition of fouling 

 communities, their structure is always characterized by clear-cut 

 domination by a small number of species. The species which are dominant 

 in these communities are usually representatives of groups which are far 

 removed from each other in the systematic and ecologic aspect (Turpaeva, 

 1967). In these communities, there is no competition among dominant 

 species for food, and the negative effect which they have on each other 

 is minimized. 



An example of such a structure is the fouling community on the 

 hydrotechnical installations of a metallurgical plant located at Zhdanov 

 on the north coast of the Azov Sea. Six mass species have been found in 

 this community: the hydroid Perigonimus megas , feeding primarily on the 

 copepod Calanipeda aquaedulcis ; the cirripedian Balanus improvisus , 

 feeding on phytoplankton and small zooplankton; hydroid epibionts: the 

 infusorian Zoothamnium sp. and the bryozoan Boyerbankia imbricata , 

 feeding, apparently, on microplankton and small detritus; the predatory 

 nudibranchiate mollusk Tenellia adspersa and the euryphagous crab 

 Rhitropanopeus harrisii . 



Many years of study of the composition of this community and the 

 ecologic-physiologic indices of its main species, both in nature and in 

 the laboratory, have revealed various types of interactions among them. 



A complete system of symphysiologic (B. N. Beklemishev, 1951) 

 interconnections of this overgrowth community numbers some 40 direct and 

 indirect topical and trophic links, most of which function during the 

 spring and summer, when the larvae settle, the macroscopic epibiotic 

 organisms grow, and the community as a whole is formed. The various 

 connections of this system are not equal in terms of their time of 



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