shelves we surveyed, yet they are generally the 

 most abundant of their respective families oc- 

 curring in shallow water around Wake. C. argus 

 were frequently observed outside the reef. We 

 saw few H. lacteoguttatus outside the reef; 

 however, as with the eels, assessment of a 

 squirrelfish population in the daytime by visual 

 means is impossible, especially without using 

 scuba. Groupers and squirrelfish on the reef 

 shelf may have holed up when they sensed the 

 pollution, rather than escaping to uncontami- 

 nated water outside the reef. Thus, they would 

 be very vulnerable and suffer exceptionally 

 high mortality. As far as we could determine, 

 no adult humphead parrotfish, C. gibbus, was 

 killed. Adults of this species were not seen on 

 the reef shelves that had been polluted nor in 

 unpolluted shallow areas but were numerous 

 outside the reef. It is possible that young C. 

 gibbus were among the kill and not detected. 

 C. gibbus does not develop the enlarged fore- 

 head characteristic of the adult until it is quite 

 large. During the survey we were not familiar 

 with the appearance of the young fish. Other 

 species of parrotfish (these may have included 

 young C. gibbus) were apparently very vulner- 

 able to the petroleum pollutants. If one as- 

 sumes that adult C. gibbus were also vulner- 

 able, lethal pollution probably did not extend 

 into the deeper water outside the reef. 



It is interesting to speculate as to which of 

 the various fuels caused the most mortality. 

 Within an hour after the grounding it was known 

 that aviation gasoline was escaping because its 

 distinctive smell permeated the area and even- 

 tually spread over most of the island to lee- 

 ward of the vessel. However, concurrently 

 with the gasoline. J-P4 jet fuel and possibly 

 A-1 turbine fuel were leaking. There is no 

 record of the extent of fish mortality or even 

 if any mortality had occurred the day the ship 

 grounded. The morning after the grounding 

 (September 7), black fuel oil was leaking in 

 large amounts and gross black oil pollution 

 extended along the shoreline and into the small 

 boat harbor. Dead and dying fish were first 

 noted on September 7. On September 8 there 

 was an extensive fish kill along the beach. All 

 of the aviation gasoline had apparently spilled 

 by the morning of September 9 as the presence 

 of gasoline vapor in the air could no longer be 

 detected. A large part of the black oil had also 

 spilled by September 9. but the remainder con- 

 tinued to escape at least through September 15. 

 Large quantities of aviation jet fuel, aviation 



turbine fuel, and possibly diesel fuel were es- 

 caping through September 16. However, there 

 was no evidence of fish mortality subsequent to 

 September 10. 



Near the wreck we observed that numerous 

 reef fishes and leatherback runners showed a 

 surprising tolerance to jet fuel or turbine fuel, 

 or both. The seaward side of the reef, below 

 the surface, was probably contaminated only 

 with light fuels, including aviation gasoline, 

 whereas the reef flat received both light fuels 

 and black oil mixed into the water by the heavy 

 surf. 



Although admittedly poorly documented, the 

 evidence indicates that the petroleum product 

 most lethal to fish was either aviation gasoline 

 (which contains tetraethyl lead, a known toxic 

 agent) or black oil. Other oil spillages have 

 indicated that fish are not seriously affected 

 by crude oil, which is primarily confined to the 

 surface. Laboratory experiments have corrob- 

 orated this finding. However, when a large 

 volume of heavy oil is well churned onto a 

 shallow reef flat, the mortality may be ex- 

 pected to be high. 



Considerable numbers of fish must have been 

 killed on the reef flat and washed out into deep 

 water; however, we were unable to estimate the 

 percentage of the kill that did not wash ashore. 

 By September 13, when we started our investi- 

 gation, fish apparently were not being affected 

 by oil pollution. We saw neither dead fish in the 

 water nor any fish showing signs of distress. 



We made only cursory observations on the 

 invertebrates. The turbinid snails and sea 

 urchins were the only animals found dead in 

 large numbers. The population of Turbo on the 

 south coast of Wake may have been seriously 

 depleted. Damage to many of the various small 

 invertebrates commonly inhabiting coral reefs 

 may have been severe. These invertebrates 

 have the slowest recovery rate and thus their 

 depletion would have the most profound effect 

 on the ecosystem of the reef flat. 



We observed that the fish population on the 

 reef front and slope was dense. This proximal 

 population would provide a source for rapid 

 recruitment to both the reef flat and the inner 

 harbor. 



That the fish kill was negligible when com- 

 pared with the surviving population may be 

 attributed to three main factors. First, the 

 nature of the coastal terrain was a saving fac- 

 tor, composed as it is of a narrow reef flat 

 with the water depth dropping off rapidly along 



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