FISHERY BULLETIN: VOL. 78, NO. 2 



Figure 50. — Pseudobalistes flavimarginatus , 265 mm SL, Palmyra, Line Islands. 



A single specimen, 456 mm SL, 4.5 kg, from 

 Enewetak was nontoxic. 



The stomach and gut contents of four specimens, 

 278-525 mm SL, from the Society Islands and the 

 Red Sea were examined. Echinoids, including 

 Diadema, Echinometra, and spatangoids, were 

 the main items of diet, but pelecypods, crabs, 

 polychaete tube worms, gastropods, chitons, 

 foraminifera, and algae and detritus were also 

 present. 



DISCUSSION AND SUMMARY 



As mentioned in introductory remarks, the ini- 

 tial testing for level of ciguatera at both Enewetak 

 and Bikini revealed only an occasional toxic fish 

 among the species responsible for most cases of 

 this type of poisoning in the Pacific. As expected, 

 the toxic individuals were invariably adults of 

 moderate to large size for the species. A decision 

 was then made to concentrate the fishing effort on 

 the larger individuals of the species most often 

 implicated in ciguatera. These dangerous species 

 are, in general, not common. They are at or near 



the peak of the well-known "pyramid of numbers," 

 i.e., the reduction in number of individuals one 

 encounters analyzing the populations in succes- 

 sive steps up the food chain. Consequently, much 

 more effort was expended in catching not only 

 these fishes but just the larger individuals of these 

 species. Also, it is for this reason that some rela- 

 tively common species such as Lutjanus fulvus 

 and Adioryx spinifer are represented by few 

 individuals in this report and others such as the 

 smaller species of groupers of the genera Epine- 

 phelus and Cephalopholis were not collected. In 

 highly toxic sectors these species can be poisonous, 

 though even there the incidence is low. 



A total of 551 specimens of 48 species were 

 tested from Enewetak and 256 specimens of 23 

 species from Bikini. In addition, 12 adult speci- 

 mens of Lutjanus bohar from Rongelap were tested, 

 one of which was toxic at the 5 level. The results of 

 the testing of fishes from Enewetak are sum- 

 marized in Table 1, and for Bikini in Table 2; 

 37.3% of the fishes from Enewetak gave a positive 

 reaction for ciguatoxin, and 19.7% of those from 

 Bikini. 



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