VI KEPOltT TO THE SECKETARY OF COMMERCE 



■will stand safely is the fundamental fisheries problem, for it is 

 certain that Ave can not, by artificial means of propafration, maintain 

 any of the true marine fishes if they be overfished. Fishes have been 

 studied heretofore as individuals; that is. from the morpholoo;ical 

 and taxonomic standpoint. As a result of recent developments of 

 fishery science, they now are studied as populations by methods 

 similar to those developed in collecting vital statistics. The fishery 

 itself is being studied, together with its efi'ect upon the stock, in 

 order to gauge the increase or decrease in available supply and to 

 discover if these changes are due to natural causes, over which man 

 may hope to have but little control, or to overfishing, and therefore 

 subject to regulation. It is the aim of effective fish husbandry to 

 afford proper regulation of the fishery so that the yield may reach 

 its maximum without encroaching upon the spawning reserve. 



The present state of America's fisheries should occasion real con- 

 cern for their future welfare. While their total yield has increased 

 steadily since 1880, until it now amounts to over 2,500,000,000 pounds 

 annually, valued at more than $103,000,000, there is convincing evi- 

 dence that many of our great fisheries are suffering actual depletion. 

 The importance of sea food in the balanced dietary, the rapid in- 

 crease in the population of the country, recent developments in 

 refrigeration, preservation, and distribution of sea foods, together 

 Avith revolutionary changes in methods of marketing, all show un- 

 mistakably that we are entering upon an era of exploitation of the 

 fisheries greater than ever before. The urgency and importance of 

 the practical problems of conservation, therefore, make it imperative 

 that the bureau center the attention of its own research staff upon 

 their earliest solution. 



In reviewing the w^ork of the division of scientific inquiry during 

 the past fiscal year, the continuity of effort and aim applied to the 

 major projects of investigations is a conspicuous characteristic that 

 no doubt contributes toward the satisfying progress of the work. 

 This condition is most favorable, for it is the result of the adoption 

 of a carefully planned program of research together Avith freedom 

 from interference and pressure from outside special interests that 

 would result only in continual shift of project and personnel with 

 consequent loss of efficiency. 



The salmon investigations have continued to yield detailed infor- 

 mation concerning the routes of migration and the success of spawn- 

 ing escapement in the A^arious localities, facts that haA^e been used 

 directly as the basis for modifying or improving the regulations of 

 the fisherA' in the interest of conservation. The causes and control 

 of diseases that annually have taken heavy toll of the output of 

 the many hatcheries throughout the country are yielding to continued 

 research, and the pathologist has rendered valuable aid in advising 

 hatchery superintendents in the prevention and cure of formerly 

 devastating epidemics. InAxstigations of the marine fisheries of the 

 Atlantic coast also are showing extremely promising results, espe- 

 cially in the case of the mackerel fishery, Avhere the causes for extreme 

 A'-ariation in abundance haA^e been discovered in the great success 

 or almost complete failure of spaAvning and survival in various 

 years. 



