ADMINISTRATIVE REPORT SERIES Since the beginning of the Administrative Report Series, considerable confusion has arisen concerning the system of numbering the separates composing it. Inasmuch as the Reports of the Divisions vary in order from year to year, many have found their designations as "Appendix No. I, II, III, or IV" very confusing. To relieve this, it has been decided to number them as "Administrative Report No. Inasmuch as 20 separates had already been printed in this series before starting the numbers, it was deemed advisable to begin the numbering with Administrative Report No. 21. Of course, numbers cannot be printed on those already off the press, but for the information of those who wish to know what the first 25 were, they are numbered for filing purposes as follows: No. 1. Report, Commissioner of Fisheries, 1931. No. 2. Alaska Fishery and Fur-Seal Industries, 1930. No. 3. Fishery Industries of the United States, 1930. No. 4. Progress in Biological Inquiries, 1930. No. 5. Propagation and Distribution of Food Fisheries, 1931. No. 6. Report, Commissioner of Fisheries, 1932. No. 7. Alaska Fisheries and Fur-Seal Industries, 1931. No. 8. Fishery Industries of the United States, 1931. No. 9. Progress in Biological Inquiries, 1931. No. 10. Propagation and Distribution of Food Fishes, 1932. No. 12. Progress in Biological Inquiries, 1932. No. 13. Fishery Industries of the United States, 1932. No. 14. Propagation and Distribution of Food Fishes, 1933. No. 18. Propagation and Distribution of Food Fishes, 1934. No. 22. Propagation and Distribution of Food Fishes, 1935. No. 24. Fishery Industries of the United States, 1935. No. 25. Propagation and Distribution of Food Fishes, 1936. Note that the last Commissioner's Report was for 1932. Since then its place has been taken by a reprint from the Report of the Secretary of Commerce under the title "Bureau of Fisheries." Inasmuch as it is no longer a Bureau publication, it is not numbered; but it will be supplied to any who request the Report of the Commissioner for any year since 1932. II 1 Administrative Report No. 39, Appendix I to Report of the U. S. Commissioner of Fisheries for 1940. Approved for publication May 13, 1940. III INTRODUCTION Progress in biological inquiries during 1939 recounts numerous advances and extensions of scientific knowledge of the Nation's aquatic resources. From the research of the Division of Scientific Inquiry there is emerging a philosophy of fishery management that is finding direct application in State laws for the protection and development of the commercial fisheries and in the more active measures adopted for the rehabilitation and maintenance of the recreational fisheries. The growth and expansion of fishery research throughout the almost 70 years that have elapsed since the establishment of the old U. S. Fish Commission is an interesting study. The early scientific investigations were either casual surveys or attempts to discover and to catalogue the aquatic resources. The strictly scientific surveys of the Albatross, the Fish Hawk, and the Grampus that bridged the end of the last and the beginning of the present century were paralleled by or followed by special investigations of specific phases of our inland water resources. From those studies there resulted a basic fund of oceanographic, ichthyological, and general zoological information. That basic research program has never ceased, for the spirit of discovery still persists throughout all of the Bureau's scientific endeavors. The purely systematic and distributional studies of fishes and invertebrates of commercial importance did not long remain ends in themselves. It was not only necessary to know what we had but also how each item behaved in relation to its environment. Thus lifehistory and ecological studies of the most important fishes, molluscs and crustaceans were conducted with the object of obtaining information that would, suggest means of insuring a continuation of the supply at a safe level of abundance. Statistical methods of analysis were adopted to interpret the large quantities of data that were accumulated. Fundamental concepts of fishery management were developed and applied and biological investigation thus become an indepensable tool of conservation. The specific aim of the research concerned with both marine and fresh-water fisheries is an analysis of the fluctuations in natural abundance and production in an attempt to discover methods of balancing commercial yields against reproductive activities. other words, the continuation of any fishery resource demands that an adequate breeding population always remain and that commercial production should remove only the surplus, or "annual crop." In Unfortunately, the depletion of many commercial fishery resources has been allowed to progress to a critical point before the financial support of investigation to discover means of protection was provided. Any attempts at rehabilitation based on scientific findings, necessarily are slow, especially since the fishing industry must be maintained at as high a level of production as is consistent with the preservation and recovery of the stocks. The research programs 1 |