THE SEA OF OKHOTSK 817 



In the southwestern part of the Sea there are south-boreal and even sub- 

 tropical species of the families Gobiidae (5 species), Clupeidae (2 species), 

 Mugilidae, Carangidae, Oplegnathidae, Tetrodontidae and Pleuronectidae 

 (two species each), and Rhombidae, Engraulidae, Salangidae, Scombreso- 

 cidae, Syngnathidae, Scombridae, Trididae, Sparidae, Monacanthidae, Raji- 

 dae, Lamnidae, Embiotocidae (one species each). There are 29 or 30 such 

 species in all, about 10 per cent of the whole fish fauna. 



There are 12 species of deep-water oceanic fish, among them 4 Macruridae, 

 3 Bathylagidae and one species each of Gonostomidae, Chauliodontidae, 

 Alepisauridae, Scopelidae, and Moridae (T. Rass, 1954). There are 44 second- 

 ary deep-water species, among them 27 Liparidae, 10 Zoarcidae, 5 Cottidae, 

 and 2 Scorpaenidae (P. Schmidt, 1950). 



There are about 20 species of commercial fish in the Sea of Okhotsk: 

 Squalis acanthias, Clupea pallasi, Oncorhynchus keta, O.gorbuscha, O. kisutch, 

 O. nerka, Sahelinus malma, Osmerus eperlanus dentex, Cololabis sajra, Gadus 

 macrocephalus, Theragra chalcogramma, Eleginus gracilis, Sebastolobus 

 macrochir, Pleurogrammus azonus, Hippoglossoides elassodon, Lepidopsetta 

 bilineata, Limanda aspera, L. punctatissima, Platessa quadrituberculata, 

 Pleuronectes stellatus. The most important of them are herring, pink salmon, 

 keta, brook trout, pollack, rock trout and plaice. 



About 870 thousand tons offish were caught in the Okhotsk Sea in 1955. 

 The catch in 1936 was estimated at 700 to 780 thousand tons (T. Rass, 1948) ; 

 it has increased mainly owing to the development of the herring, plaice, 

 pollack and rock trout fisheries. 



In the northern part of the Sea of Okhotsk herring feeds on more orjess 

 large plankton (Themista libellula, Metridia and Calanus finmarchicus). 



Commerical crabs (Paralithodes camtschatica, P. brevipes and P. platypus 

 and Chionoecetes opilio) feed in summer (M. Khun and L. Mikulich, 1954) 

 on various mass forms of benthos : Echinodermata (Strongylocentrotus and 

 Echinarachnius, various starfish and Ophiura), Mollusca, especially Serripes 

 groenlandicus, Cardium ciliatum and Macoma calcarea, various Polychaeta, 

 Ascidia, especially Pelonaia corrugata and Boltenia echinata, and various 

 Peracardia. 



Using A. P. Andriashev's data (1939), L. Vinogradov (1948) distinguishes 

 three zoogeographical regions in the Sea of Okhotsk : the Glacial Okhotsk, the 

 western Kamchatka and the southeastern Sakhalin. 



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