BUREAU OF FISHERIES XIX 



during the year included a study of the homing instinct of pink salmon 

 in Alaska, an investigation of the red salmon of the Copper River, 

 and a study of the red-salmon runs of the Bristol Bay district. The 

 compilation and analysis of the statistics of the salmon fisheries of 

 central Alaska were completed during the year. Intensive investiga- 

 tions of the red-salmon run of the Karluk River were continued as a 

 part of the general program of determining the normal return from 

 known escapements of spawning fish. 



In the Chignik River, the Copper River, and in certain sections of 

 Bristol Bay similar investigations are under way. In undertaking 

 an investigation of the pink salmon in southeastern Alaska, the most 

 pressing problem was the early settlement of the question of the 

 relative strength' of the homing instinct in this species. Forty-six 

 salmon streams were visited and data collected. 



Field work on the Columbia River was restricted to the recovery 

 of mature fish that had been marked years before as fingerlings to 

 determine how long the fingerlings should be held at hatcheries before 

 planting. The experiment further substantiated the parent stream 

 theorj", but failed to indicate any advantage of one age of liberation 

 over another. 



The bureau has published a very complete report on the herring 

 fishery of Alaska, in which the occurrence of distinct racial units in 

 the stock is demonstrated and the relation of catch composition to 

 fluctuations in abundance with a summary of the evidence of deple- 

 tion is presented. 



FISHERIES OF THE GRE.\T L.\KES 



Investigations of commercial fisheries of Lake Erie and Lake Huron 

 were continued. The study of the relative destructiveness of gill 

 nets and trap nets of various sized meshes was completed and served 

 as a basis for the new regulations |)nssed in Ohio. They also served 

 as a basis for the revision of the commercial fisheries laws in Michigan 

 and Indiana, and for recommendations offered to Wisconsin, Min- 

 nesota, and New Yftrk. As a result of the bureau's continued effort, 

 all the States bordering the (Ireat Lakes except Minnesota have now 

 introduced the recommended method of collecting fishery statistics 

 showing the daily catch together with the amount of gear employed. 



Cooperative investigation of the limnology of Lake Erie to discover 

 normal conditions favoring fish growth as well as possible effects of 

 pollution or other factors limiting fish production, undertaken jointly 

 by the bureau and the States of Ohio and New York and private 

 institutions, was completed duiing the year, and data are being com- 

 piled and analyzed. In addition, the bureau cooperated directly 

 with the Ohio division of fish and game in conducting an intensive 

 linmological investigation of the western end of Lake Eiie in connec- 

 tion with the studies on the distribution of larval and postlarval fish 

 and the possible eflFects of pollution. 



INTERNATIONAL INVESTIGATION OF THE LAKE CHAMPLAIN FISHERY 



DISPUTE 



Personnel of the Bureau of Fisheries cooperated with Canadian 

 investigators in an investigation of the fisheries of Lake Champlain 

 to settle the dispute between the sportsmen of the L^nited States and 



