EAST-CENTRAL AND SOUTH PACIFIC OCEAN (FIGURE 5) 



Bioluminescence has been observed along the Pacific coast of Mexico 

 and Central America throughout the year. The majority of displays are 

 sheet type and glowing-ball type. Strong bioluminescence occurs in the 

 Gulf of California during autumn. Beebe (19^2) observed bioluminescence 

 neeir Acapulco, Mexico during November. He described the display as "a 

 mass of boiling turquoise foam" extending behind the ship and noted "a 

 narrow intense curved line of pale green extending out from the side of 

 the ship as if a luminous serpent were gliding with us over the surface." 

 Brilliant displays of bioluminescence have been reported in Bahia Ballena, 

 Costa Rica in March. 



In the western approaches to the Panama Canal, biol\iminescence occurs 

 most frequently from January through June. The displays are primarily 

 sheet type and glowing-ball type. Unusual displays of crescent- shaped 

 "phosphorescence" and patches of pale green light often are reported. 

 The crescent- shaped light apparently was not affected by the movement of 

 a ship and most probably was caused by pulsations of the ship's engine, 

 similar to incidents reported in Asian waters. Bright balls of "phos- 

 phorescence" are commonly observed in February. 



In the vicinity of the Galapagos Islands, marine life is rich and 

 includes a number of bioluminescent species. Beebe (192U) found the 

 marine life very distinct at night, each organism "glowing from a phos- 

 phorescent silhouette." Copepods and medusae are the main bioluminescent 

 forms in this region. Beebe also described concentrations of organisms 

 capable of causing luminescent displays that he observed between Cocos 

 Island and the Galapagos. He noted a gigantic current rip in April 

 caused by two westward flowing currents; at the juncture of the currents 

 the water was so f\ill of plankton that it resembled soup. Single-celled 

 organisms capable of lighting up the sea at night also were reported by 

 him. Salps were present in great numbers. This enormous concentration 

 of plankton continued for several nights. Noctiluca glowed in the water 

 at night just south of Cocos IslanS. in May. 



The ocean off Peru and Chile within the Peru Coastal Current is 

 highly luminescent. However, marine life farther offshore in the Peru 

 (Humboldt) Current is meager, and only occasional displays of light have 

 been observed. Along the coasts of Peru and Chile, bioluminescence has 

 been known to occiir most frequently from September through April. 



The most intense sheet-type displays are said to occur along the 

 Peruvian coast from December through April, when "aguaje" (sick water) 

 develops in coastal waters. The water becomes greatly discolored 

 sometimes bright red or various shades of brown and often, because of 

 decomposing marine forms, gives off an offensive odor of hydrogen 

 sulfide. At night the bioluminescence is often extremely brilliant. 

 During periods when "El Nino" extends much farther south than normal, 

 as into northern Chilean waters, the water becomes highly discolored 



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