The Sharks— Part Two 339 



Soupfin shark {Galeorhinus zyopterus). 



Courtesy, California Board of Marine Fisheries 



For a time, fishermen made so much money from this shark's liver 

 that they dubbed it "gray gold." If an accounting were to be made, 

 however, it would undoubtedly show that, in the long run, the Soupfin 

 has cost the fisherman more money than it has earned him. It seeks in- 

 shore waters from northern British Columbia and Alaska to central lower 

 California, and wherever it goes it attacks netted fish or feeds upon 

 fishes sought by fishermen— from sardines and anchovies to mackerel 

 and salmon. 



A4ales are seldom caught. A study of some 5,000 Soupfins caught off 

 California showed that only 31 were males. Females are heavier and 

 longer than males— 6^ feet compared to 6 feet; 100 pounds compared to 

 60 pounds. 



The same or a very similar species is known in England as the Tope, 

 Penny dog, Toper, Miller's dog, or Rig. The School shark of Australia 

 (Galeorhinus australis Macleay, 1881) is also very similar to the Soupfin. 



THE LAKE AND RIVER SHARKS 



A single known species of shark, the Lake Nicaragua shark {Car- 

 charh'miis nicaraguensis Gill and Bransford, 1877), has fully adapted 

 itself to Hfe in fresh water. This large shark, now believed identical 

 with C. leiicas, the Cub shark, known to reach 8 feet in length and re- 

 ported to grow to at least 10 feet, lives in Lake Nicaragua, the great lake 

 of that Central American country, whose only connection with the sea 

 is the winding, rapids-filled, 1 30-mile San Juan River, which flows into 

 the Caribbean on the eastern coast of Nicaragua. 



The Cub shark (also known as Ground or Bull shark) is itself a 

 roamer into fresh, or at least brackish, waters. It has also been found in 

 the iMiraflores Locks of the Panama Canal, where the waters of numerous 

 lakes mingle with the waters of two oceans. It has been taken in Lake 

 Yzabal, Guatemala, and has been reliably reported in the Atchafalaya 

 River of Louisiana, 160 miles from the sea. Also, Cub sharks allegedly 



