518 BIOLOGY OF THE SEAS OF THE U.S.S.R. 



Table 215. Changes in the Azov Sea benthos biomass in gjm 2 {after V. P. Vorobieff 



and I. Stark) 



1934-35 1950 1951 1952 



Spring Autumn July April July October April July October 



Sea of Azov 241-7 496-0 183-3 199-2 391-2 267-0 252-3 292-2 448-1 



Gulf of Taganrog 34-0 — 192-2 179-4 248-4 441-8 — 53-8 — 



Yield of benthos- 

 eating fish (% of 

 the 1934-35 

 yield) 100 37-7 55-1 53-6 



Fish 



Qualitative composition. The fish population of the Sea of Azov proper 

 consists of 79 species. Among them 19 are migratory or semi-migratory forms 

 (Acipenseridae, Clupeidae, Percidae and Pleuronectidae) and 13 are fresh- 

 water ones. Cyprinidae, Gobiidae, Acipenseridae, Clupeidae, Percidae and 

 Pleuronectidae families are outstanding in respect of the number of their 

 forms. N. M. Knipovitch (1932) divides the fish of the Sea of Azov into 

 seven different groups. 



(7) Representatives of the Mediterranean fauna which have become 

 naturalized in the Sea of Azov, where they form the main mass of settled 

 population and have sometimes evolved already into separate endemic 

 species, as for example the Azov brill (flatfish Bothus torosus). 



(2) The Mediterranean immigrants which spend part of the year in the 

 Sea of Azov and then move back into the Black Sea or even the Sea of Mar- 

 mora (mullet, red mullet, anchovy). 



(3) Representatives of the Mediterranean fauna, irregular visitors to the 

 Sea of Azov (mackerel, tuna). 



(4) Autochthonous relicts of Pontic fauna which do not leave the Sea of 

 Azov (Percarina maeoticd). 



(5) Autochthonous relicts of Pontic fauna which leave the Sea of Azov 

 periodically for spawning in the rivers (different migratory fish). 



(6) Autochthonous relicts of Pontic fauna which spend part of their life in 

 the Black Sea, part in the Sea of Azov, and part in the rivers (herring — 

 Caspialosa pontica, Caspialosa tanaica, beluga). 



(7) Fresh-water organisms. 



Quantitative estimate offish. A most valuable and so far unique attempt at a 

 direct census of fish, suggested by Yu. Marti, was carried out by V. Maisky 

 (1940) in the Sea of Azov. In August and September of 1936 the whole of the 

 Sea of Azov was covered with about two hundred hauls using fine-meshed 

 lampara in the open parts of the Sea and scraper off the shores. Each series 

 of net hauls took 10 to 12 days. The shallowness of the Sea of Azov makes 

 the use of the lampara or similar equipment specially handy for a census of 

 fish throughout the Sea (Fig. 246). 



