live a long time and are capable of fasting for long periods, expending 

 the high-calorie fat and waxy esthers. An increase in the concentration 

 of waxy esthers gives the Copepoda neutral buoyancy, compensating for 

 the loss of energy during the longer active swimming stage. For these 

 forms, as for deep-sea species, food specialization is characteristically 

 slight, with a higher share of detritus in the diet and the ability to 

 change methods of feeding, trapping all potential food when its concentration 

 is low (Vinogradov, 1968; Mullin, 1963; Mauchline, 1966; Poulet, 1973, 

 1974). The food spectrum is particularly broad among the eurytopic 

 species which inhabit the oligotrophic water areas. For example, Mysis 

 rel icta in the summer feed on detritus, phyto- and zooplankton, while in 

 the fall, with the beginning of the regular vertical migrations, they 

 eat only Cladocera ; Metridia longa in the summer is primarily a phyto- 

 planktophage, in the winter feeding on the young of the Copepoda (Lasenby, 

 Langford, 1973; Haq, 1967). The same features of nonselectivity are 

 inherent in the epiplankton filter feeders Fritil laria and Oikopleura 

 (Madin, 1974). The neritic Temora longicornis and C entropages h amatus 

 can also eat the spores of the P haeocystis , formerly considered inedible 

 (Jones, Haq, 1963). Omnivorous tendencies increase in the higher latitudes, 

 both in predators such as the polychaete Tomopteris septentrional is or 

 the copepod Pareuchaeta norvegica , the number of which is relatively 

 stable (Kielhorn, 1952; R. Williams, 1974; Dodson, 1975), and in phytophages. 

 £. hyperboreus may form a surface and deep-water population in the same 

 location, the deep-water population being distinguished by a high level 

 of consumption of microzooplankton. C^. hel golandicus may winter exclusively 

 by carnivorous eating (Corner et al., 1974), and C. h yperboreus normally 

 forms eggs on a diet of "meat" (Lee, 1974). The utilization of animal 

 food by plankters generally increases when food concentrations are low 

 (Gaudy, 1974). 



The time factor is extremely important for the trophies of the Arctic 

 community. Bacterial mineralization and the decay of dead tissue occur 

 more slowly in cold water (Harding, 1973), which preserves a larger supply 

 of food for second-order consumers. The breeding of a number of invertebrate 

 species in the autumn and winter allows the resources of food to extend 

 throughout the year. The basis of the biomass of the Arctic community 

 is created by populations of relatively large, slowly growing organisms with 

 slow metabolism. This also is facilitated by the great length of life cycles 

 (1-2. sometimes even 3 years) of Parathemisto , Sagitta , Thysanoessa , etc. 

 In the boreal waters, these animals have shorter cycles (Bogorov, 1940; 

 McLaren, 1966, etc.). 



2,3. The Seasonal Course of the Process of Production in 

 the Arctic Community 



Let us briefly study the actual picture of production, basically on 

 the example of the Barents Sea, which is included entirely in the Arctic 

 basin. Its plankton population is representative for the Arctic community. 

 It is also important that the Barents Sea is an epicontinental body of 

 water, while a huge shelf zone is typical for the Arctic. 



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