BUREAU OF FISHERIES 89 



ever, tlio major oljjoctivcs still lie ahead; tho accuiati' evaluation of 

 the factors cau.sin<x ijood or poor Hshing seasons which will enable us 

 to forecast any important increases oi- decreases in the hachlock catch; 

 ami the accurate determination of irrowth rates, mortality rates, and 

 miirration, which will enable us to determine the minimum size below 

 which it is eccmomically wasteful to capture haddock. This infor- 

 mation is vital for the intelli<ient exploitation of this resource. Its 

 attainment depends on the availability of facilities for work at sea 

 involvinir the study of abundance and mortality of haddock below 

 commercial size and the study of migrations. 



The regular spring prediction of abundance of mackerel for the 

 1934 season was issued by the Bureau near the beginning of the sea- 

 son. At that time it appeared that the abundance would l)e nearly 

 the same as in the previous season and would have provided a catch 

 approximating 54.000,000 pounds if exploitation had been normal. 

 This amount being in excess of the probable market demand, the 

 industry, under authority provided by its Code of Fair Competition, 

 curtailed its mackerel seining activities. In this manner the results 

 of scientific research have been useful to the industry. The trend 

 toward planned exj^jloitation renders more urgent the need for ad- 

 vances in scientific knowledge of this fishery. Badly needed inves- 

 tigations of the reasons for variations in the rate of annual decline 

 of the several year classes and variations in their seasonal appearance 

 in different areas have had to be deferred because of the lack of means 

 for their pursuit. 



Investigations of the shore fisheries of the Middle Atlantic States 

 were continued on a greatly reduced scale. It was necessary to 

 abandon several series of field observations before conclusive results 

 were secured, thereby diminishing the value of the results obtained 

 through funds expended on these observations in previous years. 



Results of tagging experiments have demonstrated that certain of 

 the more important species migrate extensively over the entire con- 

 tinental shelf betw^een Massachusetts and North Carolina, hence can- 

 not be protected effectively b}" uncoordinated regulations of individ- 

 ual States. Since the winter trawl fishery is conducted outside the 

 jurisdiction of the States, the continued growth of this fishery adds 

 greatly to the difficulties of protection under the present system of 

 independent legislation by the several States. 



Because of the interstate and extraterritorial nature of the fishery, 

 the responsibility for securing knowledge essential for the conserva- 

 tion of this important natural resource is clearly Federal. There is 

 a widespread demand on the part of commercial fishermen and an- 

 glers in the Middle Atlantic States for resumption and extension of 

 the scientific studies necessary to provide a sound basis for formula- 

 tion of a wise conservation policy. 



The shrimp investigations conducted by the Bureau in cooperation 

 with the States of Louisiana, Texas, and Georgia have continued the 

 field work throughout the entire range of the commercial shrimp 

 fishery w-ith various modifications to meet the special needs of the 

 problem. Definite evidences have been gathered which show that 

 the shrimp migrate. The nature and extent of their migrations are 

 now being studied by means of population .and racial analyses, and 

 preliminary marking experiments are under way. 



