BUREAU OF FISHERIES XXI 



BIOLOGICAL FISHERY INVESTIGATIONS 



The research activities of the scientific staff are addressed to the 

 oonservation of the Nation's aquatic food resources through en- 

 couraging and advising the States in their regulation of commercial 

 and spoi't fishing, in perfecting methods of water farming and fish 

 culture, and in providing the industries with sound and, in some 

 oases, advance information as to the trend of the supply of com- 

 mercial fishes. Major projects of research are conducted in each of 

 the geographical interior and coastal sections of the United States. 



Early in the fiscal year the division undertook an investigation of 

 the haddock fishery — the most important fishery of the New 

 England area. The fishery is subject to considerable fluctuations in 

 yield; and recent evidences of decline in abundance, coupled with a 

 tremendous expansion of the industry as a result of the packaged-fish 

 business, have given rise to fears of serious depletion in the fishery. 

 A comprehensive plan of investigation in the interest of conservation 

 and the proper development of the resource, involving studies of 

 changes in abundance of the stock and the possibilities of serious 

 depletion, has been adopted, but such studies require considerable 

 time for the production of results of practical value. Nevertheless, 

 one phase of the investigation already has yielded results which 

 promise to have signal value to the industry. A new type of savings 

 ti'awl has been developed to permit the escape of virtually all fish 

 below commercial size limits without reducing the catch of market- 

 able fish. If this is adopted by the fishing industrj^, it should not 

 only accomplish material economies in operation of the fishing 

 vessels, but should be a positive factor in the conservation of the stock 

 of fish in the sea. 



Near the end of the fiscal year an agreement was reached with the 

 California Division of Fish and Game for the conduct of a coopera- 

 tive investigation of the trout and steelhead salmon situation in that 

 State, and it is anticipated that the investigation will eventually 

 include other Pacific coast areas. The streams of the western moun- 

 tains have become so popular with anglers and vacationists that they 

 are no longer able to withstand the strain of intensive fishing. New 

 and improved methods of fish culture, of stocking, and of regulation 

 must be devised and adopted to protect and augment the steelhead 

 salmon runs and the trout supplies of these waters, and an investiga- 

 tion has been planned under the auspices of the two organizations 

 uniting skill and material facilities on a large scale in the hope of 

 meeting the situation. 



FISHERY INVESTIGATIONS OF THE ATLANTIC AND GULF COASTS 



Investigations of the changing abundance of the more important 

 food fishes along the Atlantic coast and the causes of such changes 

 with their implications as to remedial measures have proceeded Avith 

 gratifying results. Fluctuations in the mackerel fisliery continued to 

 follow the principle of dominant year classes with a consistency that 

 promises increased accuracy of predictions as more seasons are added 

 to the experience iqDon which forecasts are based. 



Much of the work at sea has been greatly handicapped through the 

 lack of a fisheries research ship capable of operating trawls and 



