418 U. S. BUREAU OF FISHERIES 



the latter. It therefore has not been considered necessary to install 

 means of preventing the seaward migrating fingerlings from entering 

 the turbines. 



A study also was made of means of directing the route of travel 

 of migrating fish in places such as the rapidly flowing water dis- 

 charging from the spillway gates and power wheels. Particular 

 attention lias been given to the electric fish diverter. The nature of 

 electric fields produced by various means of applying electricity to 

 the water have been studied in the laboratory. The more favorable 

 of these soon are to be applied in field tests. 



SHELLFISH INVESTIGATIONS 

 Paul S. Galtsoff, in charge 



The scope of the shellfish investigations was greatly enlarged by 

 a special appropriation of $100,000 for the study of oyster pests, and 

 the development of practical methods of their control in the Atlantic 

 and Gulf States. The investigations on oyster and hard clam cul- 

 ture were continued in the waters of New England, South Atlantic 

 States, and Puget Sound. A special allotment of $20,000, to be spent 

 over a period of 18 months, was provided by the P. W. A. for a 

 study of the failure of oyster culture in York River, Va., allegedly 

 caused by pulp mill wastes. All the work has been carried out by 

 the regular staff of the Bureau of Fisheries augmented by 20 tem- 

 porary investigators, and 50 assistants whose period of employment 

 varied from 3 to 9 months. Splendid cooperation was received from 

 the various States, the P. W. A., and transient reliabilitation camps 

 which supplied about 110 relief laborers for the field investigations. 



OYSTER-PEST CONTROL PROJECT 



The oyster-pest investigations comprised three major problems : 



(1) the starfish infesting the waters of New England and the 

 North Atlantic States; (2) the drill, in the Delaware and lower 

 Chesapeake Bays and occurring as far south as the Gulf of Mexico; 

 and (3) the so-called leech, the recent outbreak of which has wiped 

 out extensive areas of oyster producing bottoms in Florida. The 

 problems of the destruction caused by the boring sponge and the 

 borer, although of lesser importance, were also included in the 

 program. 



Practical methods that can be used by the oyster industry for the 

 control of these pests must be based on a thorough knowledge of their 

 life histories, and an understanding of their habits and activities. 

 The applicability of control methods must be determined by large- 

 scale experimentation. 



In order to provide for efficient management of these investiga- 

 tions tlie entire Atlantic and Gulf area has been divided into sec- 

 tions with centers at Woods Hole, Mass. ; Wickford, R. I. ; Milford, 

 Conn.; Bivalve, N. J.; Solomons, Md. ; Beaufort, N. C; and 

 Apalachicola, Fla. 



New England section. — Under the direct supervision of Dr. Galt- 

 soff, studies of the starfish and drill along the Massachusetts coast 

 were begun in June. Surveys were made to determine whether the 



