742 



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



bottom-dweller, and the Atlantic cod the ova of a pelagic fish. Many fish of 

 the Far Eastern Seas move to calm waters for spawning. 



P. Moiseev (1953) maintains that a series of biological and morphological 

 peculiarities, in particular an increase in fertility {Table 301), spontaneous 

 spawning, bottom ova, a shortening of the incubation period and a higher 

 rate of growth within the first years of life, have developed as a result of the 

 great variety of species of fish in the Far Eastern Seas, including the carni- 

 vores. 



Moiseev opposes the point of view, formerly held by many ichthyologists, 

 on the poor prospects of the development of fisheries of the near-bottom and 

 bottom-living fish in the Far Eastern Seas; he considers that this industry 

 might yield an output as high as that of the Atlantic Ocean. If, at the moment, 

 the bottom and near-bottom living fish of the northern part of the Pacific 



Table 301. Fertility {thousands of ova) of certain Pacific and Atlantic fish 

 {P. Moiseev, 1953) 



Species 



Pacific Ocean 



Atlantic Ocean 



Cod 



Navaga 



Limanda aspera 

 L. limanda 

 Capelin 

 Herring 



per 1 kg of fish by weight. 



produce 8-7 million centners as against the 22-2 of the northern parts of the 

 Atlantic, this is due only to the poor development of the industry. 



The northwestern part of the Pacific Ocean is also exceptionally rich in 

 marine animals. M. Sleptzov (1952) writes that this area is inhabited by ' seven 

 species of pinnipeds representing all the three families of the order Pinni- 

 pedia; eared seals (fur seal and sea-lions), earless or proper seals (marine, 

 and ribbon seals, and ringed seals), walrus, and 30 species of the order Cetacea 

 (22 species of toothed whales and 8 species of baleen whales) '. Sea otter may 

 also be added to this list of sea mammals. 'Huge herds of white dolphins and 

 dolphins, shoals of cachalots and rorquals feed in these waters from spring to 

 autumn, since these areas are very rich feeding grounds for pinnipeds and 

 Cetacea.' Cachalots come there from the tropical zones of the Pacific; fur 

 seals move there from Japanese waters. Among all the 35 species the cachalot 

 and two species of seals, Phoca hispida ochotensis and Hystriophoca fasciata, 

 are the most important for the industry. The annual yield of cachalots reaches 

 7,000 head with a total weight of about 1-5 to 1-7 million centners. The marine 

 seal from the Komandorski Islands and Tyuleny Island in the Okhotsk Sea 

 is the most valuable for its fur. 



Kamchatka crab {Paralithodes camtschatica), the annual yield of which 

 has risen in recent years to 400,000 centners, occupies a special place among 



