FISHERY BULLETIN: VOL. 78, NO. 2 



the lagoon at Jaluit. Becke (1901) recorded 

 poisonous fishes from Rahk (Ebon), the south- 

 ernmost atoll in the Marshalls (reference from 

 Halstead 1967). With the takeover of the Mar- 

 shalls by Japan at the start of World War I ( 1914), 

 the documentation of ciguatera at these islands 

 shifted to the Japanese. Hishikari ( 1921), Matsuo 

 (1934), and Hiyama (1943) published on poisonous 

 fishes at Jaluit. Some fishes in the vicinity of 

 Utirik Island, Utirik Atoll, have been reported as 

 poisonous (Hydrographic Office, U.S. Navy 1945). 



Historically, Jaluit was the principal atoll of the 

 Marshalls. It was the center of government, had 

 the greatest shipping activity, and the highest 

 population (1,683 in 1933). As a result of military 

 activity during World War II, Kwajalein (the 

 largest atoll in the world) and Majuro became 

 more important. Majuro is the District Adminis- 

 trative Center of the islands. By 1958 the popula- 

 tion was 3,336 (compared with 783 in 1935), 

 whereas the population at Jaluit had declined to 

 1,112 in 1958 (Robson 1959). 



Concurrent with the buildup in population and 

 commerce at Majuro and Kwajalein was the ap- 

 pearance of ciguatera (or at least the first records 

 in the literature of its incidence). Halstead and 

 Lively (1954) reported one death and five persons 

 seriously ill from the consumption of a moray eel 

 at Kwajalein. Bartsch et al. (1959, table 2) 

 documented the marked increase in cases of fish 

 poisoning at the hospital at Majuro; there were 22 

 in 1955 (all in the last half of the year), 100 in 

 1956, and 211 in 1957. Banner and Helfrich ( 1964) 

 stated that the atolls in the Marshall Islands 

 where poisonous fishes are most commonly found 

 are Kwajalein, Mille, Ailinglaplap, Jaluit, and 

 Majuro. They tested numerous fishes of many 

 species from Enewetak (formerly spelled 

 Eniwetok) collected in 1958, but none were found 

 to be toxic. Balaz,^ on the other hand, interviewed 

 Chief Johannes, the last remaining traditional 

 chief of the Enewetak people, at Majuro on 15 

 March 1974. Johannes stated that poisonous 

 fishes were known at the atoll at the time of his 

 departure in 1946 from the islands of the eastern 

 side between the deep passage and the northern 

 end. It should be pointed out, however, that a 

 short-term field survey of ciguatera at an atoll, 

 such as that carried out by Banner and Helfrich, is 

 difficult to equate to the continuous human bioas- 



'George H. Balaz, Research Associate, Hawaii Institute of 

 Marine Biology, pers. commun. 1974. 



202 



say of a population of native people dependent on 

 fishes as their principal source of protein. One 

 should also emphasize that even in highly toxic 

 sectors, the percentage of poisonous fishes that 

 will cause ciguatera when eaten is small. Never- 

 theless, only a few cases in an area may be needed 

 to prevent residents from fishing in that area. 



The atolls of Enewetak and Bikini are located at 

 the northern end of the Ratak Chain 165 mi apart 

 between lat. 11° and 12° N. The native people of 

 Bikini were moved from their island to Rongerik 

 Atoll and later to Kill Island when a series of 

 nuclear explosion tests were carried out by the 

 United States beginning in 1946. The people of 

 Enewetak were transferrred to Ujelang Atoll in 

 1947 for the same reason. When repatriation of 

 these Micronesian people was contemplated, a 

 question arose as to the current level of toxicity of 

 the food fishes of Bikini and Enewetak. 



Fluctuation in the toxicity of fishes in reef 

 ecosystems has long been recognized (Banner and 

 Helfrich 1964; Cooper 1964; Halstead 1967; and 

 Helfrich and Banner 1968). Furthermore, Randall 

 (1958) hypothesized that disruptions of the marine 

 environment resulting in the creation of new sur- 

 faces (particularly the repetitive formation of new 

 surfaces) in potentially ciguatoxic areas may be 

 linked to outbreaks of the toxemia. This 

 hypothesis has received support from Cooper 

 (1964) who related toxic sectors in the Gilbert Is- 

 lands to the locations of wrecks and anchorages, by 

 Helfrich et al. (1968) who documented the first 

 outbreak of ciguatera at Washington Island, Line 

 Islands, following the wreck of the MS Southbank 

 in late 1964, and by Bagnis (1969) who reported 

 numerous cases of ciguatera at the previously 

 nontoxic atoll of Hao in the Tuamotu Archipelago 

 after the atoll was altered as a staging area for 

 nuclear testing at Mururoa. 



de Sylva (1963) misinterpreted this hypothesis. 

 He stated that Randall found poisonous fishes in 

 estuarine areas. On the contrary, Randall re- 

 ported toxic fishes in the Society Islands from cer- 

 tain areas of slight or intermittent freshwater 

 drainage which are ordinarily flushed with clear 

 water from the open sea. During periods of heavy 

 rain the freshwater runoff to a normally marine 

 habitat may cause death of stenohaline sessile 

 marine animals, thus forming a new surface for 

 benthic growth. 



After stating that the basic toxic organism must 

 be benthic, Randall (1958) wrote, "Since obli- 

 gately herbivorous fishes and detritus-feeding 



