Atlantic Coastal Waters of NW Africa^ Spain, Portugal, and France 



Along the Atlantic coast of northwestern Africa and in the western 

 approaches to the Strait of Gibraltar, displays occur during the spring 

 and autumn months. On the Moroccan coast, in such places as the Bay of 

 Agadir, there also is an abundance of luminescent organisms during the 

 winter. In February I96O these organisms luminesced brightly during the 

 earthquake which caused so much destruction on land. In October and 

 November 1955 moderately intense displays were noted near Casablanca, 

 Morocco. The light was bright enough to cause a "milky" glow which ex- 

 tended 2 feet from the sides of various oceanographic instruments as they 

 were raised and lowered into the water. These particulajr displays were 

 due to large concentrations of luminescent protozoans primarily, although 

 large flashes of light by ctenophores or jellyfish could be observed when- 

 ever an instrument jaj^red these organisms. 



Some very spectacular displays occur in various bays of western Spain 

 and Portugal. Pinto (19^9) gave an account concerning intense luminescence 

 and "red water" near Lourinha, Portugal in September 19^^ caused by a bloom 

 of the dlnoflagellate Gonyaulax . The' luminescence caused some panic among 

 local fishermen according to Pinto. The light given off was blue-green, 

 and the intensity increased when the water was disturbed. Displays such 

 as these may occur along the western Iberian coast from April through 

 December, although the most vivid displays are seen in the late summer 

 and early autumn. One of a number of wartime reports concerning bio- 

 luminescence and submarine tracking comes from this region. In November 

 1918 the last German U-boat (U-3^) to be destroyed during World War I 

 was easily tracked because the water was so "phosphorescent" at the time 

 that the submarine could be seen moving under the water "glowing" and 

 outlined by "sea fire." 



In the Bay of Biscay French and Spanish fishermen utilize summer 

 bioluminescence to track fish at night. The trails left and the peculiar 

 flowing movement of fish schools through luminescent waters provide them 

 with evidence as to the type of fish present. Noctiluca, so common to 

 most of the coastal regions of the world, causes bioluminescence in the 

 various bays and inlets along the coast of France. Quatrefages (1850), 

 a French naturalist, noted the intense luminescence of large concentra- 

 tions of this particular pinkish organism in water near such ports as 

 Dieppe, St. Malo, Brehat, and Ostend (Belgium). These organisms appeared 

 in the surface waters from July through September. 



English Channel and North Sea 



In the English Channel, bioluminescence is most evident from April 

 through November; however, displays can occ\xr during all seasons. Winter- 

 time bioluminescence is not unusual in this region, especially along the 

 English coast. For example, glowing forms of fishes and the long lumin- 

 escent trails they leave in the water have been observed in the dark 

 surface waters during February near Plymouth. "Brilliant green lines" 



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