84 REPORT OP THE SECRETARY OF COMMERCE 



fisheries of the Great Lakes. The shrimp fishery of the South At- 

 lantic and Gulf has also been studied with the aim of discovering 

 and preventing depletion of the supply; and the salmon and herring 

 fisheries of Alaska are undergoing scientific analysis as a basis for 

 their regulation. Aquicultural investigations include studies on the 

 improvement of hatchery technique for both cold- and warm-water 

 fishes and the plannino- of rational stocking policies in interior waters. 

 Shellfishery investigations have been directed toward improving the 

 quality of the oysters in the North and Middle Atlantic section and 

 toward increasing the production by cultural methods in the South 

 Hnd on the Pacific coast. Even with reduced appropriations for field 

 operations the Bureau's technical staff has made valuable contribu- 

 tions to science, all of which have practical application to the welfare 

 of the fishery industries, to the angler, and to the Avater farmer, 

 assuring continued productiveness of the natural supply and in- 

 creased production and improved quality of cultivated aquatic 

 products. 



FISHERY INVESTIGATIONS OF THE ATLANTIC AND GULF COASTS 



Fishery investigations have been concerned with the haddock and 

 mackerel in the New England section ; with the squeteague or weak- 

 fish, the butterfish, scup, and flounders in the Middle Atlantic sec- 

 *'"^n; and with the great shrimp fishery in the South Atlantic area, 

 investigations on shellfish in these areas will be considered later. 



The haddock fishery, which is the most important on the Atlantic 

 coast, reached a maximum production in 1927 and has fallen off 

 sharply in succeeding years until a minimum was reached in 1931 

 of less than 183 million pounds. The maximum yields around 1927 

 were the result of unusually successful spawning during the years 

 1920 and 1922. A study of the statistics of the yield per unit of 

 effort, combined with a study of the biology of the haddock stock, 

 particularly size and age composition, growth rate and distribution, 

 indicate that since these years no abundant year broods were pro- 

 duced until 1930. It was anticipated that when this abundant 

 year class reached marketable size there would be an increase in 

 landings. During the spring of 1933 catches by the trawling fleet 

 have been extremely good, but prices have declined in the mean- 

 time so that only moderate production in the fishery has resulted. 



Reduced funds have prevented the conduct of studies on the abun- 

 dance of year classes below commercial size. Tagging experiments 

 to trace the migrations of the haddock have also been reduced, but 

 determination of migrations is essential to an accurate prediction of 

 the trend of the fishery on Georges Bank, and this study will be 

 resumed at the earliest opportunity. 



The regular spring prediction of the mackerel fishery for 1933 

 was issued by the Bureau near the beginning of the season. At 

 that time it appeared that a catch of about 44 million pounds was 

 in prospect. Economic conditions, however, will prevent the fleet 

 from realizing this yield, although the catches during the early 

 part of the season indicate an abundance somewhat in excess of 

 that of the previous year. Difficulties in compiling 1933 estimates 

 of the max^kerel fishery emphasize the need for a more thorough 



