The Sharks— Part Two 333 



Great Blue shark {Prionace glauca). 



Courtesy, Harvard Museum of Comparative Zoology 



spected marine scientists: Doctors John Treadwell Nichols and Robert 

 Cushman Murphy. 



The Great Blue is probably one of the unidentified villains of many 

 sea stories about ravenous sharks. Sailors claim, for instance, that a Great 

 Blue will appear astern of a ship when a man aboard dies, and will 

 ghoulishly trail the ship until the body is committed to the sea. Nichols 

 and Murphy told of a voyage aboard a whaler when a seaman died. Two 

 or three Great Blues, about 7 feet long, and another species of shark, did 

 appear at the vessel's stern that day. "The old, old maritime conviction 

 that these hated brutes had come expressly for the body was breathed 

 about the ship," the scientists reported. "But . . . the sharks paid no 

 attention when the dead man was consigned to the waters, and they 

 followed uninterruptedly in our wake for several days." 



Though an oceanic shark, the Great Blue occasionally noses into 

 shore in its ceaseless search for food. It is the most abundant large oceanic 

 shark of the Atlantic. Nichols and Murphy told of seeing "hundreds- 

 even thousands" in relatively small areas of the Atlantic. In an hour's 

 run 4 to 10 miles off Block Island in 1943, 28 were counted, and 150 to 

 200 were seen from a single boat in one day. 



Along the North American Pacific coast, it is found both on the high 

 seas and in waters close to shore from British Columbia to the Gulf of 

 California. When warm currents bathe California's bathing and skin- 

 diving mecca of Monterey Bay, numerous Great Blues sweep in. They 

 are easily spotted, for they often swim with both their dorsals and their 

 tail fins exposed. Sometimes they even "bask" at the surface. They are 

 easily identified by the big, sickle-shaped pectoral fins, as long as their 

 heads, and by their striking, dark indigo-blue color, which shades to 

 snow white on their undersides. Their sleek form, their long, graceful 

 pectoral fins, and their coloring make them one of the most beautiful of 

 sharks. 



The Great Blues may be the most abundant of the pelagic sharks of 

 the Pacific. On U.S. Fish and Wildlife Service tuna fishing explorations 

 in the Pacific, as much as 46 per cent of the catch has been stolen or 



