THE SEA OF AZOV 



491 



months E M (fi E w. Ш а К Ж ш 



S. V 



S Ш i HI С EJ I Ш 



YEARS 



/93 7 



/947 



f943 



/949 



\/ ШШ2 СЗз G34 CZ35 



5ZD7 E3<5 888 э E^/i? 



Fig. 233. Alterations of biomass of certain zooplankton species of the Sea of Azov 

 proper : 1 Copepoda ; 2 Rotatoria ; 3 Tintinnoidea ; 4 Mollusc larvae ; 5 Cirripedia ; 

 6 Cladocera; 7 Hydrozoa larvae; 8 Polychaeta larvae; 9 Mysidacea; 10 Others 



(Okul, 1941). 



Copepoda development is even greater than in the open part of the Sea of 

 Azov (on the average 70 per cent of all the zooplankton biomass ; in fact 

 1,500 mg/m 3 , chiefly consisting of Calanipeda aquae dulcis). The relict form 

 Heterocope caspia is very characteristic of the Gulf of Taganrog ; there is a 

 considerable admixture of fresh- water species in the most eastern part of the 

 Gulf. Cirripedia larvae play a substantial part in the Sea of Azov in June ; 

 42 per cent of zooplankton biomass consists of them, they yield up to 270 

 mg/m 3 . Their numbers are much smaller in the Gulf of Taganrog. 



Among the other groups which go to form the Sea of Azov zooplankton, 

 that of the marine Infusoria Tintinnoidea should be mentioned first ; in spite 

 of its minute size, it gives a mean annual biomass of 39 mg/m 3 (9-6 per cent 

 of the total zooplankton). During the period of its greatest development, in 



SEA OF AZOV 



GULF OF TAGANROG 



too- 



90- 

 80- 



70- 

 60- 



so- 

 но- 

 во- 

 го- 



to ■ 

 о ■ 



II III IV 



m VIII IX X XI XII 



Fig. 234. Composition and distribution of Copepoda in the plankton of the Sea of 

 Azov and the Gulf of Taganrog according to the months of the year (Okul, 1941). 



