CHUKCHI 

 PENINSULA 





o« 



ppi^ I I Amphipoda 

 I j Copepoda 

 liii-ilj Tunicata 



^B Larvae* 

 I I Yana 



• Polychaeta+Gaslropoda+Bivalvia+Ciffipedia+Ophiura+Echinoidea 

 +Asteroidea+Decapoda+Foromdea 



Fig. 4. Ratio between average abundance and qualitative composition ot 

 zooneuston in investigated regions of the Bering and Chukchi Seas. 



TABLE 9 



Coefficients of faunistic similarity and 



differences of zooneuston of the Bering 



and Chukchi Seas (according to materials 



collected during the summer. 1988). 



Differences 



The indices of faunistic similarity in the other regions are 

 high, which shows that their fauna are partly or completely 

 isolated. The exchange of species is insignificant or there is 

 none, while conditions forexistence of zooneuston aredifferent. 



In the Bering Sea, distribution of zooplankton can be 

 divided into five faunistic groups (Vinogradov, 1956;Brodsky, 

 1957); south Bering Sea, north Bering Sea, east and west 

 neritic, as well as, deep-water Bering Sea. After confirming, 

 with the help of literature data ( Mescheryakova, 1 970; Motoda 

 & Minoda, 1974; Kolosova et ai. 1987), the composition of 

 indicator species characterizing the first four groups, an analysis 

 was carried out of their distribution in the neuston layers of the 

 Bering and Chukchi Seas (Fig. 5). The center of south Bering 

 Sea faunistic group was situated over the deep water part of the 

 south and east regions of the Bering Sea, and in the way of two 

 tongue-like intrusions entered into the Gulf of Anadyr. The 

 center of the north Bering Sea is broken in the area. One part 

 is found south of the Gulf of Anadyr, another in the central and 

 northeastern part of the Chukchi Sea. The center of the west 

 neritic group is situated in the Chirikov Gulf and Chukchi Sea. 

 One south Bering Sea faunistic group is characteristic for the 

 south and east regions of the Bering Sea. The main part of the 

 east neretic and faunistic group is located in the northeast of the 



CHUKCHI 

 PENINSULA 



'¥• 





^ 



^ 





o^ 



m 



A 

 B 

 C 

 D 



.Scheme of distrihulion (6()'/i and more dominating) ol Bering Sea 

 faunistic groups in the neuston layer of the Bering and Chukchi Seas; 

 A - south, B - north. C - west neritic, D - east neritic groups. 



190 



