The incidence of bioluminescence increases northward along the east 

 coast of South America. Many luminescent forms are carried north by 

 the F5alkland Current and develop in large numbers in regions such as 

 the convergence zone to the east of the Rio de la Plata. 



Strong biolimiinescence occurs within and seaward of the Rio de la 

 Plata. This region is one of the most biolumine scent parts of the South 

 Atlantic. Here, Darwin (l8i)-5) observed 



"a sea that presented a wonderful and most beautiful spectacle 



the vessel drove before her bows two billows of liquid 



phosphorus, and in her wake she was followed by a milky train. 

 As far as the eye reached the crest of every wave was bright, 

 and the sky above the horizon, from the reflected glare of 

 the livid flames, was not so utterly obscure as over the 

 vault of the heavens." 



Commander Charles Wilkes (18^5) on board the USS VINCEMIES during the 

 famous exploring expedition of the U. S. Navy in l838-i4-2 observed in 

 this convergence zone "that the water was much discolored due to salps 

 during the day, and as night closed in the sea became very luminous, 

 the vessels passing through the water leaving long bright trains behind 

 them." Just after noting this luminosity, the ship encountered a tem- 

 perature drop in the water, probably due to the Falkland Current, but 

 the sea remained luminescent on each side of this front. 



Caribbean Sea 



More luminescence occurs in the eastern Caribbean than in the 

 western portion. Frequent displays occur along the coast of Venezuela, 

 principally in the Gulf of Paria and in the Golfo de Venezuela. 



Exceptional bioluminescence may be observed in the bays located 

 along the coasts of various islands encompassing the Caribbean Sea. 

 Bahia Fosforescente (Phosphorescent Bay), located on the south coast 

 of Puerto Rico, is outstanding in this respect. In this bay sheet-type 

 biolimiinescence occurs year round because of a continuously abundant 

 dinoflagellate community. The bay itself acts as a culturing vessel, 

 complete with the proper nutrients, the right temperature, and other 

 ecological factors needed to sustain a continuing rich community of 

 dinoflagellates. Bioluminescence is intense when the water is agitated 

 by boats or fishes. Bays, such as this, usually are bordered by man- 

 groves, with continual drainage from the land into the bay. 



Oyster Bay, near Falmouth, Jamaica is another bioluminescent bay, 

 in which sheet-type bioluminescence occurs throughout the year. Harvey 

 (1952) visited the region and found the water "marvellously beautiful, 

 with every fish that moved outlined in fire and every wave looked as if 

 it were aflame." He indicated two responsible organisms, the marine 

 dinoflagellates Ceratium and Pyrodinium bahamense . Research concerning 

 bioluminescence and bioluminescent organisms was conducted in this bay 



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