neritic zone, the dominant species are recruited from the complex specific 

 for this zone: Acartia l ongiremis , A. clausi , A. bifilosa , A. tumida , 

 Centropages hamatus , £. mcmurrichi , Temora l ongicornis . In estuaries, to 

 these forms we must add L imnocalanus grimaldii , Senecella cal anoides , 

 Drepanopus bungei , Derjuginia toll i , Heterocope appendiculata , h[. b oreal is , 

 Eurytemora hirundoides , and E. herdmani , the Cladocera and the rotifers. 

 The biomass of the estuarian complex may reach 30 g/m3, but namely its 

 productivity fluctuates from season to season by hundreds and thousands of 

 times. 



The most important reason for the seasonal summer-fall decrease in 

 biomass of zooplankton in the Arctic community is consumption by planktono- 

 phagous fish, fingerlings of benthic fish, as well as sagittae, medusae 

 and ctenophores. The elimination of the Copepoda by fish occurs in all 

 stages of ontogenesis, with not only phytophages, but also predators 

 involved in the process (Sysoyeva, 1973; Aslanova, 1971). There are a 

 multitude of invertebrate predators: for example, in the southeastern 

 portion of the Barents Sea in July and August, the number of ctenophoran 

 Bolinopsis infundibulum reaches 170 per cubic meter, Pleurobrachia pileus- - 

 30-40 per cubic meter, the medusae Rathkea , Obel ia , Aglantha d igitale , 

 Tiaropsis mul ticirrata --up to 3000 per cubic meter (Zelickman, 1961a, 1966, 

 1969) . The rate of elimination of the Calanus depends directly on the 

 population of B ol inopsis : the correlation coefficient between the overall 

 elimination of Calanus and the occurrence of ctenophores is 0.93±0.06. 

 In August alone, the Ctenophora may decrease the population of Calanus by 

 a factor of 5 (Nesmelova, 1968). The peak of the population of medusae 

 and ctenophores is independent of temperature and is related to the 

 population of prey, occurring usually 2-4 weeks after the peak of Copepoda 

 biomass, regardless of the hydrologic specificity of the year, but the 

 duration of the period of high population of Coelenterata is closely 

 related to the temperature (Zelickman, 1955; Zelickman, 1972). The 

 number of invertebrate predators is in turn regulated by a secondary 

 mechanism--their consumption by more narrowly specialized predators-- 

 other ctenophores and meduses. For example, Beroe cucumis consumes only 

 Bol inopsis . Tiaropsis multicirrata , when highly concentrated, after 

 consuming the crustacean zooplankton, begins eating Rathkea octopunctata , 

 turns to cannibalism, etc. (Zelickman, 1960b, 1965; Zelickman, Kamshilov, 

 1960; Zelickman, 1972; Conover, Lalli, 1974). 



Let us trace this scale of creation of living matter in the Arctic 

 community, using the Barents Sea as an example. During years with Calanus 

 domination, the curve of the dynamics of biomass in the plankton has a 

 single peak (see Fig. 5); as the number of Calanus drops, the curve takes 

 on more than one peak and the maxima are shifted in time. The annual pro- 

 duction of Calanus finmarchicus averages 250-300 mg/m3, about 90% of the 

 annual production occurring between April and early October (Kamishilov, 

 1958). The higher the biomass of the Calanus , the greater its relative 

 significance in the plankton. It is logical to presume that with full 

 realization of its productive potential, C alanus would expel the remaining 

 zooplankton. Extrapolating the curve of relative significance of C alanus 

 (Fig. 8) to 99.9%, we obtain the value of the theoretically maximum possible 

 spring-summer biomass of zooplankton (excluding Protozoa, Medusae, Ctenophora 

 and other crustaceans) in the upper 50 m layer is about 3 g/m^. This level 

 of biomass has actually been observed repeatedly. For example, in June-July 



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