THE SEA OF AZOV 503 



Table 207 



it is, moreover, possible to show that the comparative percentage of the young 

 stages in the regions of intensive feeding of fish is very low as compared to 

 regions where fish do not feed. On the Zhelezinskaya and Eleninskya Banks, 

 where fish feed intensively, the young of Cardium forms only 12-4 per cent 

 in comparison with the adults, while along the Arabat Strelka, where there 

 are fewer fish, this percentage rises to 55-7. 



Vorobieff (1944) has estimated the consumption by fish of young Cardium 

 at 3 1 to 77 per cent by comparing these data. Knowing the numbers of settled 

 young it can be calculated that the fish consume 644 specimens with a bio- 

 mass of 102-4 g/m 2 . Similar data were obtained by Vorobieff when he deter- 

 mined the amount of young Cardium eaten by fish from their intestinal con- 

 tent. I.t was calculated in the same way that the amount of one-year-olds 

 consumed by fish is 70 per cent as compared with those under one year, and 

 184 per cent of two-year-olds. The loss of Cardium due to consumption by 

 fish from May to November in the biocoenosis under consideration is given 

 in Table 208 (calculations were carried out for those under one year). 



After making some corrections Vorobieff concludes that 661 g/m 2 of 

 Cardium are consumed. The difference in the average biomass, from spring 



Table 208 



Consumption 

 Age group No. of specimens Biomass 



per 1 m 2 g/m 2 



Under one year 



One-year-olds 



Two-year-olds 



Three-year-olds 



Four-year-olds 



Total 1,354 664-94 



