Florida where smaller baits are trolled (Nakamura 

 and Rivas, 1972). At present there is no way of telling 

 whether the better catches off South Pass result from 

 larger baits, better fishermen, or greater abundance of 

 blue marlin. 



5.43 Catches 



Ueyanagi et al. (1970) have given the annual 

 longline catches (1958-66) of blue marlin for the 

 Atlantic Ocean on the basis of numbers offish caught 

 rather than total weights. Their graph shows the es- 

 timated catches of blue marlin by year is as follows: 



Annual longline catches (1962-70) of blue marlin 

 were recently published by Gottschalk (1972) for the 

 entire Atlantic and the eastern Pacific. In the Atlan- 

 tic, the catches are expressed in the number of fish 

 caught: 



Data collected from the sport fishery of the northern 

 Gulf of Mexico during the 1971 season (May to Oc- 

 tober) show that 84 blue marlin weighing a total of 

 8,995 kg (19,788 lb) were caught. Of these, 20 were, 

 males weighing 28 to 127 kg (62 to 280 lb) and 64 were 

 females weighing 21 to 224 kg (46 to 492 lb). Average 

 weight of males was 71 kg (156 lb) and that of females 

 was 118 kg (260 lb). The average weight of all 84 fish, 



males and females combined, was 107 kg (236 lb). The 

 fish were caught out of South Pass, La., and Pen- 

 sacola, Destin, and Panama City, Fla. 



6 PROTECTION AND MANAGEMENT 

 6.1 Regulatory (Legislative) Measures 



6.11 Limitation or reduction of total catch 



At present, there are no limitations or reductions of 

 any kind applying to the blue marlin fishery. A steady 

 decline in the catch, however, since 1962 (see 5.43 

 above) has called attention to the need for regulatory 

 measures. Analysis of the annual catches of blue 

 marlin in the Atlantic from 1958 to 1962 shows the 

 pattern of a virgin fishery when first opened to ex- 

 ploitation. Instead of leveling off, however, the catch 

 has steadily declined since 1962, despite increased ef- 

 fort, from 111,000 fish to 11,000 in 1970. I have no in- 

 formation on whether or not the average size of the 

 blue marlin has also declined. 



6.12 Protection of portions of population 



There are no closed areas or seasons and there are 

 no limitations on gear. There are, however, 

 limitations on the use of blue marlin for food in the 

 United States according to the degree of mercury con- 

 tamination of the flesh. Shomura and Craig (1974) 

 reported on the total mercury levels found in the 

 white muscle tissue of 37 blue marlin caught in 

 Hawaiian waters. Thirty of the 37 fish had mercury 

 levels that exceeded the 0.5 ppm. level used as a 

 guideline by the U.S. Food and Drug Adminstration 

 as fit for human consumption. The mercury levels 

 ranged from 0.7 to 7.86 ppm. in fish weighing between 

 43.5 and 410.9 kg (96 and 906 lb, respectively). 



7 POND FISH CULTURE 

 Not applicable. 



LITERATURE CITED 



ANRAKU, N., and Y. YABUTA. 



1959. Seasonal migration of black marlin. [In Jap., Engl, 

 synop.] Rep. Nankai Reg. Fish. Res. Lab. 10:63-71. 



BAKER, A. N. 



1966. Food of marlins from New Zealand waters. Copeia 

 1966:818-822. 

 BARTLETT, M. R., and R. L. HAEDRICH. 



1968. Neuston nets and South Atlantic larval blue marlin 

 (Makaira nigricans). Copeia 1968:496-474. 

 BRIGGS, J. C. 



1960. Fishes of worldwide (circumtropical) distribution. 

 Copeia 1960:171-180. 



14 



