BUREAU OF FISHERIES IX 



pinfish, and menhaden, all of which are of considerable economic 

 value. 



The investigations of the bay scallop in North Carolina are virtu- 

 ally completed. This fishery is limited to the vicinity of Beaufort but 

 is so concentrated as to jneld nearly $250,000 in products annually. 

 Recommendations have been offered concernino- the economic harvest- 

 ing of the crop without endangering the supply and for increasing 

 the yield by farming methods. 



Although practical methods of terrapin culture have been devel- 

 oped at the Beaufort laboratory and production has been conducted 

 upon a commercial scale through cooperation with the North Caro- 

 lina conservation department, certain problems still remain to be 

 solved in order to increase the efficiency of the station. These are 

 concerned j^rimarily with certain diseases that have taken a con- 

 siderable toll of the terrapin reared during the winter in the heated 

 brooder house. Two conditions are recognized, which maj^ be distinct 

 diseases — one resulting in softening of the shell and the other in pro- 

 duction of cancerous sores on the tail, feet, and elsewhere. Prelimi- 

 nary investigations indicate that they are not bacterial diseases, but 

 there is considerable evidence that the}^ are nutritional disorders. Ex- 

 pert advice on the problem was offered by the Pe])per Laboratory, 

 School of Medicine of the University of Pennsylvania, and additional 

 experiments are being undertaken to determine the cause of the dis- 

 ease and to effect a cure. 



Field investigations on the fisheries of Texas were completed early 

 in the fiscal year, and the remainder of the year was spent in analyzing 

 the data collected. Special attention has been given the redfish, 

 black drum, and spotted trout, each of which yields nearly 1,000,000 

 pounds annuall}^ A report is nearly ready for publication summariz- 

 ing the pertinent features of the life history of each of these species, 

 describing their spaw^ning, rate of development, and movements, and 

 offering recommendations concerning their conservation and the de- 

 velopment of additional fishing areas. Progress has been made on 

 the taxonomic study of the fauna of the Texas coast. 



FISHERIES OF THE FACIFIC COAST AND ALASKA 



The program of fishery investigation adopted in 1921 by the 

 Pacific Salmon Investigation Federation has continued as the basis 

 of the bureau's investigation of the entire salmon fisheries of the 

 Pacific coast. The chief aim of this work is to discover how large 

 a spawning reserve is necessary in order to maintain commercial 

 runs in the waters of the Pacific Coast States and Alaska. As the 

 bureau's responsibility is greatest in Alaska, where the salmon fishery 

 is administered and regulated by the Department of Commerce, the 

 chief attention has been given that region. Extensive tagging experi- 

 ments were undertaken to determine the migration routes taken by 

 tlie fish in the major fishing areas. In addition, weir counts have 

 been continued on the Karluk and Chignik Eivers and age analyses 

 of the entire run in these rivers have been made. The relation 

 between spawning escapement and the total return has been observed 

 for several years with such exactness that predictions of succeeding 

 runs have been attempted with marked success. For example, tlie 



