26 



FISH AND GAME COMMISSION 



were constructed or modified to pack albacore arc now a<rfrressively reaeli- 

 ing out for their share of yellowfiu tuna, and skipjack. In 1947 one com- 

 pany sent its mother-ship into Costa Kican waters, and in the spring and 

 summer of 1947 purchased on the grounds for delivery to Astoria a full 

 load of 3^ellowfin and skipjack. Tn the winter of 1948 a second nortliern 

 company had two mother-ships on tlie grounds purchasing fish from 

 our fleet for delivery to the Columbia River. 



In self-defense, a number of California packers have followed this 

 lead; and by the summer of 1948 a number of tenders, or mother-ships, 

 were either in actual operation, or in process of conversion. The mother- 

 ships have apparently come to stay; and this marks an important devel- 

 opment initiated in this period. 



The purse seiners, which in earlier years fished for yellowfin and 

 skipjack only in Lower California waters in that season when fish were 

 there available, have now by force of circumstances already mentioned, 

 extended their operations as far as Costa Rica. This has necessitated 

 enlarged refrigeration plants on the vessels, and some modification in 

 equipment. The extended range in operations has also resulted in the 

 construction — or conversion — of a number of large vessels for purse- 

 seining. For the first time the largest purse seiners are now comparable 

 in size and tonnage with the large live-bait tuna boats. 



Figure 9. A California purse seine boat leaving port. This type of vessel, of which 



there are over 200 in California, fishes for sardines, tuna, and mackerel principally. 



(Photoc/raph by Vernon M. Haden, San Pedro) 



This expansion in purse seine operations has resulted in consider- 

 able friction between the two basic types of gear; and their respective 



