the Japanese longline fishermen, many of 

 whom would be expected to recognize the 

 species, have reported catches consistently in 

 every one of the 13 years studied. Ueyanagi 

 et al. (1970) believe that the black marlin in 

 the Atlantic are strays from the Indian Ocean. 



Figure 11 shows the distribution of the 

 catches at a level of 1 fish per 10,000 hooks 

 or higher for each quarter of the year. Catches 

 are extremely low outside of the areas out- 

 lined, but can be quite high within them — up 

 to 186 per 1,000 hooks in the first quarter — 

 although most of the rates are less than 10 

 per 10,000 hooks. 



Little can be said of the general distribu- 

 tion of the species. A concentration appears 

 in the Gulf of Guinea, off Africa, in the first 

 and second quarters, and concentrations 

 appear along the coast of South America in 

 the first and third quarters, related perhaps 

 to a South Atlantic concentration in the fourth 

 quarter. 



The fact that the concentrations appear off- 

 shore and distant from population centers may 

 explain why the species has not been recorded 

 in the sport fishery. 



the distribution of spearfish rather than sail- 

 fish. 



Concentrations of sailfish occur along the 

 east coast of South America in all four quarters, 

 extending in the second and third quarters 

 along the north coast of South America. In the 

 second quarter the concentrations reach into 

 the Caribbean and the southern Gulf of Mexico. 

 Another concentration may be seen on the 

 west coast of Africa from about lat 5°N to 

 about 10 °N in every quarter except the third. 



Most concentrations of sailfish do not go 

 much above 6 fish per 1,000 hooks — excep- 

 tions occur only in the second quarter in the 

 eastern Caribbean with over 35 per 1,000 

 hooks and on the north coast of South America 

 with over 15 per 1,000 hooks. The concentra- 

 tion in the central North Atlantic in this 

 quarter, probably spearfish, rises to just over 

 14 per 1,000 hooks. 



Figure 2 demonstrates that there has been 

 a steady increase in catch per unit of effort of 

 sailfish and spearfish during 1956-68, although 

 the combination of more than one species in 

 the statistics makes interpretation of the 

 phenomenon difficult. 



SAILFISH AND SPEARFISH 



SKIPJACK TUNA 



The status of the spearfishes in the Atlantic 

 is not entirely clear; Tetrapturus pfiuegeri, 

 the longbill spearfish, occurs in the open 

 Atlantic, and T. belone occurs only in the 

 Mediterranean. In addition there may be one 

 other species of spearfish in the Atlantic, 

 whose status is presently unclear. The statis- 

 tics published by the Fisheries Agency of 

 Japan combine sailfish and spearfishes in a 

 category almost certainly equivalent to that 

 reported by Shiohama et al. (1965) as "other 

 marlins." 



Ueyanagi et al. (1970) suggest that the 

 sailfish lives close to land, while the longbill 

 spearfish is found offshore. We assume that 

 all concentrations in Figure 12 at or above 

 the level of 6 fish per 1,000 hooks are sailfish, 

 except for the two in the second and fourth 

 quarters in the central North Atlantic. S. 

 Hayasi and S. Ueyanagi suggest (personal 

 communication) that all of the open sea con- 

 centrations shown in Figure 12 may reflect 



Longline catches of skipjack have been very 

 low — Table 1 shows that in certain years none 

 were reported by the Japanese longliners. 

 There is a strong suggestion in the data that 

 this represents a lack of reporting rather than 

 a lack of catch — compare the data in Table 1 

 for 1959 with those for 1962. There is prece- 

 dent, however, for considering longline catches 

 of skipjack at least as an indication of distri- 

 bution (Miyake, 1968). 



Figure 13 shows the distribution of the 

 catches at a level of 1 fish per 10,000 hooks 

 or higher for each quarter of the year. Average 

 catches inside the contours are 10 fish per 

 10,000 hooks or less, except for one instance 

 on the north coast of South America in the 

 fourth quarter when the catch reached nearly 

 40 per 10,000. In general, catches outside of 

 the contours shown are very low. 



Probably the major value of Figure 13 is 

 the indication that skipjack are very widely 

 distributed in the Atlantic. 



20 



