GENERAL CHARACTERISTICS OF FAR EASTERN SEAS 



743 



the resources of the Far Eastern Seas. Two other species of the genus {P. platy- 

 pus and P. brevipes) are taken (Fig. 365) in small numbers along with the 

 Kamchatka crab. The other two species of this genus are not found in Soviet 

 waters. Only some of the smaller sized true crabs (Chionoecetes opilio, Erima- 

 crus isenbecki and Telmessus cheiragonus) might become important commer- 

 cially. So far, however, their role in the catch is insignificant. Kamchatka crab 

 is taken almost throughout the whole area of its distribution (L. Vinogradov, 



Fig. 365. Places of concentration of commercial crabs (Vinogradov). 1 Paralithodes 

 camschatica ; 2 P. platypus ; 3 P. brevipes. 



1941, 1945). P. brevipes has a similar area of distribution. The other four 

 species are found from the Bering Sea to the Sea of Japan. The largest crabs 

 belong to the genus Paralithodes, which forms large aggregations of commer- 

 cial importance. Kamchatka crab assembles off the shores of the u.s.s.R., 

 Japan and Alaska. The largest yield of this crab is taken off the western coast 

 of Kamchatka. Seasonal migrations of the Kamchatka crab consist of travel- 

 ling to the coast (at depths of 1 5 to 70 m) for feeding during the summer, and 

 a return to lower layers (1 10 to 200 m), and even down to 270 m in the Sea of 

 Japan, where the water is better heated (1-5° to 2-5°) during the cold months 

 when the surface waters are much cooled. The migration routes of the Kam- 

 chatka crab cover dozens of miles (up to 100). The average daily distance 



