PROGRESS IN BIOLOGICAL INQUIRIES, 1932 107 



of the fish in the commercial catch were looked over for individuals 

 that previously had been marked as fingerlings. Only about 100 

 marked iisli were recovered, but these few have added materially to 

 our knowledge of the habits of the fish and the interpretation of their 

 scales. They have shown, for example, that a great part of the fin- 

 gerlings that are observed throughout the summer in the river below 

 the lakes are not seaward migrants. They evidently move back into 

 the lake and do not migrate until the following spring. This habit 

 has not been observed in other rivers. 



Special attention was given to determining the distinctive charac- 

 ters of the presumed two races of red salmon that populate the two 

 lakes in the Chignik system. In order to permit following a group 

 of fish of known origin an effort was made to catch and mark finger- 

 lings in the upper lake. The unusually great number of mature fish 

 interfered with seining for the fingerlings and only about 9,000 were 

 caught and marked. 



The run of mature red salmon at Chignik in 1932 was the largest 

 for many years. This large run was derived mainly from 5-year 

 fish that developed in the upper lake and 6-year fish that developed 

 in the lower lake. 



COPPER RIVER RED-SALMON INVESTIGATION 



Because of the much reduced appropriation made available for 

 biological investigations in Alaska, there were no employees of the 

 Bureau detailed to continue the exhaustive study of the red-salmon 

 runs of the Copper River which was begun in 1929. Seton H. 

 Thompson, formerly engaged in this work, was detailed during the 

 year to assist the Chief of the Alaska Division with administrative 

 duties. In order that the work already completed would not be 

 entirely lost, arrangements were made for the continued sampling of 

 the daily catches of red salmon and for the collection of statistics 

 relative to the daily catch of salmon by each fishing boat operating 

 in the Copper River area. This work was done under the direction 

 of Warden N. O. Hardy, and excellent data were obtained. 



An examination of the spawning grounds after the close of the 

 commercial fishing season was also undertaken by Warden Hardy, 

 and it was concluded that the escapement, although approximately 

 equal to that of the preceding year, was not adequate. 



The study of the scales taken by random sampling of the commer- 

 cial catch has been continued by Mr. Thompson at odd times, and 

 the results of previous scale readings have been tabulated and 

 analyzed. Twelve distinct groups are represented in the samples 

 examined to date. These groups consist of red salmon maturing at 

 ages varying from 3 to 7 years which have spent from 1 to 4 winters 

 in fresh water. Two of these age groups no longer appear in the 

 commercial catch because of the higldy selective 5}2-inch stretched- 

 mesh gill net now in almost universal use in the red-salmon fishery, 

 and one age group appears only occasionally. The two age groups 

 no longer taken are grilse, which samphng has indicated are always 

 males of very small size and therefore of slight importance to tlie 

 industry. In all years for which samples have been fairly complete 

 three age groups have comprised from 96 to 99 percent of the catch. 

 Of these, the fish maturing in 5 years which have spent 2 winters in 



