26 U. S. BUREAU OF FISHERIES. 



to ascend to their natural spawning grounds. It is probable that 

 the numbers of fish thus released for natural spawning exceeded 

 those involved in tlie egg collections. This substation is located 

 within 10 miles of the " top " of the Rocky Mountains, in the State 

 of Idaho, and to reach this mountain stream for the accomplishment 

 of their supreme mission in life the salmon travel approximately 

 1,500 miles without food after entering the Columbia River at 

 Astoria, Oreg. The conditions which were observed here in regard 

 to the sjilendid spring run of chinook salmon were not confined to 

 the Snake River. Similar conditions were observed in all tributaries 

 of the Columbia River frequented by the so-called spring-run fish. 

 Very excellent results in the rearing of young salmon have been 

 obtained from the use of a comparatively new article of fish food. 

 This is the immature spawn of the salmon taken by the commercial 

 fishermen. The spawn is purchased at a comparatively low cost 

 and held in cold storage until needed. In commenting on its value 

 in his annual report for 1920 the superintendent of the station states: 



The salmon fry fed on salmon spawn and beef spleen produced remarkably 

 fine fingerlings. It is by far the most satisfactory food that has ever been 

 used in this field. No trouble was experienced with the fish at any point 

 where Its use was adopted. They were uniformly sturdy and readily accepted 

 it throughout the year. 



While the expense involved in feeding fish on an extensive scale 

 is considerable, in view of the quite general belief that the future 

 supply of salmon in the Columl)ia and other rivers of the State is 

 dependent very largely on the numbers of fingerling fish released 

 from the hatcheries, the w^ork is considered of first importance. 

 Because of the long period during which so little is known of the 

 life of the salmon — from the time of the seaward migration as a 

 fingerling or yearling until its return for the reproduction of its 

 kind — it is difficult to effect any positive check on the ajctual results 

 of hatchery work. Nevertheless, the evidence in favor of the work 

 at certain points, notably in the Columbia, Clackamas, and Rogue 

 Rivers, is of a convincing nature, and it appears to fully warrant 

 the expense necessary to continue the feedino- and intelligent plant- 

 ing of fingerlings. Upward of G8,000 pounds of fish food was used 

 at the stations in the Oregon field during the fiscal year 1921. The 

 details are given in the table of fish food on page 75. 



BAIRD ( CALIF. ) STATION AND SUBSTATIONS. 

 [W. K. Hancock, Superintendont.l 



In this field are to be recorded a number of unt>oward circum- 

 stances residtiiig in a serious curtailment of the fish-cultural work. 

 From the fall run of fish the aggregate egg collections for the entire 

 field amounted to 7,910,000, as compared with 11,785,000 the preced- 

 ing year, which included 1,349,700 eggs of the spring run chinook 

 salmon taken in the McCloud River at Baird. 



Racks wore again installed in the McCloud River in time to inter- 

 cept the spring run of chinooks, but no fish appeared. This is di- 

 rectly attributable to the dam erected in the Sacramento River at 

 Redding for irrigation purposes. This dam had the effect of divert- 

 ing into the irrigation ditches most of the water in the river during 

 periods of low-water stages, and though an opening was left in the 



