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yields for all the species of billfishes in the U.S. Fishery Conservation 

 Zone around Hawaii, American Samoa, Guam, and California, is now in force. 



II. NATURE AND SIGNIFICANCE OF U.S. AND FOREIGN 

 PARTICIPATION IN THE FISHERY 



The marl ins are prized game fishes. Although the U.S. interest in 

 marl ins is primarily of a recreational nature, the commercial aspects of 

 the marl in fishery are not to be ignored. In 1976 the sale of striped, 

 blue, and black marl ins brought about $332,000 in revenue to the fishermen 

 in Hawaii .■'■ 



III. STATUS OF THE STOCKS 



1 1 1. A. Stock Structure 



Blue marl in- -Available evidence seems to indicate that the blue 

 marl in comprise a single equatorially-centered stock in the Pacific. 

 Concentrations of blue marl in occur alternately at locations on both sides 

 of the equator during the respective summer seasons. The large, apparently 

 single area of blue marlin spawning in the western Pacific, which includes 

 areas of high spawning densities in the west and declining densities to the 

 east, has been suggested as evidence for the unit stock assumption. 

 Confirmation of the unit stock of blue marlin stock structure hypothesis is 

 needed. 



Striped marl in- -Al though the stock structure of the striped marlin 

 in the Pacific is not clear, two likely hypotheses have been advanced: 1) 

 a single-unit stock suggested by the continuous, horseshoe pattern of 

 striped marlin distribution in the Pacific, and 2) a two-stock structure, 

 where a North Pacific stock and a South Pacific stock are separated roughly 

 at the equator, with some intermixing in the eastern Pacific (Figure 2). 



Bl ack marl in- -The stock structure of black marlin in the Pacific is 

 unclear, but their restricted coastal distribution and the occurrence of 

 isolated high catch-rate areas suggest the possibility of more than one 

 stock. It has been suggested tha.t two or three stocks exist: one in the 

 eastern Pacific and two in the western Pacific (Figure 3). The situation 

 is complicated by the strong possibility that black marlin from the Indian 

 Ocean mix with fish from the western Pacific. 



