PEOGRESS IN BIOLOGICAL INQUIRIES 51 



the brood would mature at the age of 7 years. To ascertain the 

 total returns from the 1,330,000 spawners in 1921 it is obvious, there- 

 fore, that the runs of each of the years from 1924 to 1928 must be 

 analyzed and the numbers of fish of each age determined. Our 

 analysis of the run of 1924 during the past season represents the 

 first of this series. To trace the complete history and fate of the 

 Karluk broods already tallied at the weir will require an analysis 

 of the runs from 1924"to 1932. 



SALMON OF THE PACIFIC COAST STATES 



During the fishing season on the Columbia River attention was 

 given mainly to the collection of data regarding returns from 

 salmon-marking experiments. Records of the capture of fourteen 

 5-year-old fish that had been marked at the Littla White Salmon 

 River station of the Bureau of Fisheries were reported from the 

 commercial fishery, and eight M-ere taken during the egg-taking 

 operations of the hatchery from which the fingerlings were liber- 

 ated. Twenty fish from this marking were taken during the 1923 

 season Mdien they were in their fourth year, and a few more may be 

 expected to return during the 1925 season. These records, though 

 few in number, are of considerable interest from the standpoint of 

 scale study, as they supply evidence which corroborates that from 

 other sources in assigning the proper significance to certain trouble- 

 some types of scale nuclei. 



Sockeye salmon from the brood of 1920, which were introduced 

 from Alaska and marked and liberated at the Herman Creek sta- 

 tion of the Oregon Fish Commission during the fall of 1921, were 

 expected to return during the 1924 season in their fourth year, but 

 none were reported from the commercial fishery and none entered 

 Herman Creek. These fish may mature as 5-year-olds and return 

 to spawn during the 1925 season, but judging from the returns from 

 former marking experiments and our general knowledge of sockeye 

 salmon,^ few if any returns are now expected. The apparent failure 

 of the fish from this experiment to survive to maturity and the quite 

 satisfactory returns from two experiments in which the young fish 

 were liberated during the spring of their .second year seem to in- 

 dicate that success in the artificial propagation of sockeyes is 

 achieved only when the fish are held until the spring of their second 

 year or are provided with conditions favorable to their residence in 

 fresh water until that time. 



A report on the Columbia RiA^er marking experiments to date, 

 which is being prepared for publication, will be completed in the 

 very near future. 



Probably the most important phase of the past season's work was 

 an investigation of the spawning grounds of blueback salmon in 

 the Okanogan River. The knowledge that this spawning district 

 exists is of considerable interest, since until it was discovered noth- 

 ing was known of the present spawning grounds of the Columbia 

 River bluebacks, and in the absence of that Imowledge it has been 

 impossible to give the fish adequate protection or to secure their eggs 

 for artificial propagation. Interest in this spawning district is 



