106 U-S. BUREAU OF FISHEEIES 



returns from escapements of similar magnitudes. Limnological data 

 from Karluk Lake are collected each year, three trips having been 

 made during 1932 for this purpose. With a knowledge of the fluctu- 

 ations occurring in the ratio of the number of migrants produced per 

 spawning fish an analysis of the limnological data should throw con- 

 siderable light on the causes of the fluctuations. 



This investigation is being carried on under the general direction 

 of Dr. Willis H. Rich of Stanford University. 



CHIGNIK RED-SALMON INVESTIGATION 



An investigation of the red-salmon runs of Chignik River, Alaska, 

 which is being conducted by Harlan B. Holmes, has continued along 

 the same general program as in preceding years. One of the princi- 

 pal objects of this investigation has been to determine the relation 

 between the number of spawning fish in 1 year and the resulting 

 number of fish in the runs of future years. From this information we 

 should learn what part of each year's run may be allowed to the 

 commercial fishery, and what part must be reserved for spawning. 



Numerous peculiarities in the composition of the runs and the life 

 history of the fish have delayed conclusions in the investigation. At 

 the very beginning of the investigation it was found that the scales 

 of the fish were confusing and that confidence in age determinations 

 based upon them would require an investigation of the life of the 

 young fish in fresh water. As this part of the investigation has pro- 

 gressed many confusing irregularities in the Hfe of the fish, which 

 would be reflected in their scales, have been observed. 



A lack of uniformity in the age composition of the catches of the 

 several traps necessitated a careful study of methods of sampling. 

 Preliminary results of this work have shown that extensive samples 

 will be required for a satisfactory age analysis of the run. 



There are many indications that the general run of red salmon in 

 Chignik River is not one homogeneous population but consists of 2 

 self-perpetuating races represented by fish that spawn in the 2 lakes 

 of the Chignik watershed. Although the fish of the two races differ 

 only slightly, if at all, in anatomical characters and appearances, they 

 have different habits. In addition to spawning in different parts of 

 the river system, they differ significantly in time of spawning migra- 

 tion, length of time spent in fresh water as fingerlings, and age at 

 maturity. There probably are significant differences in the rate of 

 mortality of the two races. 



We now have complete returns from five counted escapements. 

 Preliminary analysis of these data indicate generally larger returns 

 from larger escapements but there is considerable variation in the 

 returns from a given number of spawners. A part of this variation 

 is believed to be due to varying proportions of fish of the two races 

 in the runs. It is hoped that when the data for the two races can be 

 more accurately segregated the ratio of escapement to return will be 

 found to be less variable. 



Mr. Holmes, assisted by George B. Kelez, and Elmer E. Enterline 

 spent the months of May to September at Chignik. The routine 

 collection of data for age analysis of the run of mature fish and obser- 

 vations of the life of the young fish in fresh water were continued; 

 a program of limnological observations was started ; and a great part 



