PROGRESS IN BIOLOGICAL INQUIRIES, 193 4 355 



acquired a firsli-wator liahitat. Those fislies di.sapjx'ai' almost com- 

 pletoly from tlio streams ahovc an elevation of from l.n^K) to '2,000 

 foot. ■ 



Food for fishes, consisting principally of crustaceans and insects, 

 is abundant almost everywhere. The temperature of the waters at 

 an elevation of 2,000 feet and lii<;her is cool onouoh for rainbow trout, 

 as it rarely exceeds 70° F. About 10,000 rainbow trout fry were 

 hatched in the Loquillo National Forest from vfi^i^s received fi'om the 

 Division of Fish Culture throuijh the United States Forest Service. 

 Some 9.000 of these fry were liberated in streams within the forest 

 wliile the remaininjz; 1,000 were retained and fed principally on 

 shrimps from the local streams. Whether the ones that were liber- 

 ated have survived is not definitely known, but the ones retained and 

 fed in captivity made fairly rapid <^rowth. 



Some bluegill sunfish (Lepoinh incisor) and catfish {Anieivmis 

 vielm), presumably acquired throuofh the New York Academy of 

 Sciences, were introduced in two reservoirs in about 1913. These 

 fishes have propajjated and still are present in the two reservoirs in 

 which they were introduced. A third species, one of the crappies 

 (Pomoxis) also was introduced, and is said to have maintained itself, 

 though it was not seen during the investigation. The introduction 

 of temperate-zone fishes seems to have been so successful that more 

 trout eggs and small bluegill sunfish {Lepomis incisor) and catfish 

 {Ameimms Jiehulosus) Ave re sent during October and December 1934. 

 The prospects that these American fishes will establish themselves 

 are favorable, and it is hoped thereby to furnish sport and food for 

 the people of Puerto Rico. 



SHRIMP INVESTIGATIONS 



The shrimp investigations have continued under the direction of 

 Milton J. Lindner. As in the past, headquarters have been main- 

 tained in New Orleans, La., in offices furnished by the Louisiana De- 

 partment of Conservation. Field stations have been located at the 

 United States Fisheries Biological Station, Beaufort, N. C. : the 

 Georgia Tidewater Commission, Brunswick, Ga.; and the San Patri- 

 cio Canning Co., Aransas Pass, Tex. The Louisiana Department of 

 Conservation; the Texas Game, Fish, and Oyster Connnission; the 

 Georgia Department of Game and Fish; and the San Patricio Can- 

 ning Co. have continued their generous cooperation as in the ])ast. 

 Due to lack of funds, operation of the Black Mallard was intei-rupted 

 on August 1, 1934. Operations of this vessel will be resumed for a 

 brief period beginning January 1935. 



In conjunction Avith the Avork of the Bureau the Louisiana Depart- 

 ment of Conservation has been conducting a hydrographical survey 

 of Louisiana Avaters under the direction of James Nelson Gowanloch. 



The shrimp is the most valuable fishery resource of the South At- 

 lantic and Gulf coasts. In 1932, the latest year for Avhich statistics 

 are available, the shrimp fishery, Avith a catch of over 88 million 

 pounds and a value to the fishermen of over 2 million dollars, ranked 

 sixth among those of the Ignited States and Alaska. There are three 

 species of shrimp that constitute the commercial catch, the common 

 shrimp, Penaeus setiferus; the grooved shrimjD, P. hrasiliensis ; and 



