PROGRESS IN BIOLOGICAL INQUIRIES, 1922. 



REPORT OF THE DIVISION OF SCIENTIFIC INQUIRY FOR THE FISCAL YEAR 1922/ 



By R. E. CoKER, Assistant in Charge of Scientific Inquiry. 

 (With the collaboration of investigators.) 



CONTENTS. 



Page. 



Introduction 1 



Studies of fishes 2 



Alaslia salmon investigations 2 



Salmon investiKatioms in Pacific 



Coast States 3 



The whiteflsh and its relatives in 



the Great Lakes 4 



Fisties of Chesapeake Bay 5 



Miscellaneous studies of fishes 6 



Experimental fish cultui-c S 



Diseases and parasites of fishes 9 



Studies of river, lake, and sea 12 



Chesapeake Bay 12 



Long Island Sound 13 



Upper Mississippi River 13 



Green Lake, Wis 15 



Plankton 15 



Bottom fauna 15 



Page. 



Studies of river, lake, and sea — Con. 

 Green Lake, Wis. — Continued. 



Bottom flora 17 



International Committee on Marine 



Fishery Investigations 17 



Fresh-water mussels • 18 



Investigations of conditions of 



mussel culture 18 



Practical tests of the value of 



protection and propagation 20 



The oyster 21 



Great South Bay 21 



Long Island Sound 22 



Chesapeake Bay 22 



Pollution of waters 23 



Fish as agents in mosquito control- 24 



Reddening of salt fish 25 



The biological laboratories 25 



INTRODUCTION. 



It is an orif^inal and fundamental function of the Bureau of Fish- 

 eries to inquii£ into the causes of the decrease of food fish and other 

 useful resources of the waters, in order to seek means of checking 

 decreases where they appear and of promoting increases wherever 

 possible. Decreases of aquatic resources have occurred and are likely 

 to continue with the increased demand upon the fish-food suppl}^ 

 and with a growing population that steadily augments the number 

 of possible fishermen and sportsmen. 



There is indeed a conspicuous contrast between the histories of 

 production of land and water products, respectively. While over a 

 span of years we see with gratification a steady and noteworthy de- 

 velopment -in the yields of principal products of the land, we observe 

 at the same time, and unfortunately with generally small concern, 

 an entirely different trend with regard to the crops that are derived 

 from our waters. Wliile we grow more wheat and corn, more cattle 

 and poultry, we have less halibut and whitefish and fewer crabs and 

 lobsters. New regions have been opened to production of potatoes 

 and fruit, while considerable areas of water bottom, once productive 



, 1 Appendix XIII to the Report of the U. S. Commissioner of Fisheries for 1922. 

 Doc. No. 936. 



B. F. 



