408 U. S. BUREAU OF FISHERIES 



directly into the Yakima River. In the sontheastern section of the 

 State of Washington partial surveys of the Walla AValla River, Mill 

 Creek, and Asotin Creek have been made, and the examination of 

 the Touchet and Tucannon Rivers is finished. Surveys of Alocho- 

 man and Wind Rivers in the lower Columbia are under way, while 

 the Washougal River survey was completed. A total of 1,100 miles 

 of tributary streams was surveyed during the year. 



Because of the fact that all of the salmon and steelhead trout which 

 reach Grand Coulee Dam after its completion must be artificially 

 spawned and their offspring cared for in a hatchery, it became nec- 

 essary to know the numbers and species of these fish migrating past 

 the dam site so that proper hatchery facilities could be provided for 

 them. In connection with this problem, counting weirs were in- 

 stalled in both fish ladders of the Rock Island Dam of the Puget 

 Sound Power & Light Co. Observers were stationed there to count 

 the fish during the entire year. The total numbers of salmon and 

 steelhead trout passing over this dam in 1935 were : Chinook salmon, 

 16,310; blueback salmon, 14,013; silver salmon, 11; and steelhead 

 trout, 5,412. This counting was done in cooperation with the Wash- 

 ington State Fisheries Department. 



A couiiting weir was maintained in the fish ladder of the Tum- 

 Avater Dam on the Wenatchee River during the late summer and 

 early fall when the blueback salmon were ascending that tributary. 

 During that time 889 blueback salmon, 4 chinooks and 7 steelheads 

 ascended the ladder. Another counting weir was operated at Oro- 

 ville, Wash., where 10 chinooks and 264 blueback salmon were 

 counted. From surveys made of spawning grounds, records of the 

 Indians' catches at Kettle Falls, and other sources of evidence, it 

 appears that the majority of the fish counted over the Rock Island 

 Dam go on past the Grand Coulee dam site and seek spawning 

 grounds largely in British Columbia. Fortunately, a great deal of 

 work on the life history and habits of the salmon of the Columbia 

 has been done (by Rich, Holmes, and others) thus making that 

 phase of the investigation seemingly less pressing than some of the 

 others. However, every o])]>ortunity was taken advantage of to secure 

 material for such work. Large collections of the migrants, both 

 salmon and steelheads, were made in the Yakima River, and scales 

 were taken from steelheads and salmon at the Rock Island and 

 Tumwater weirs. 



The investigation of the mechanism of the homing instincts of the 

 blueback or sockeye salmon, initiated before Mr. Craig was trans- 

 ferred to the Columbia River work, was continued. Ten thousand 

 sockeye migrants in their second year were marked and liberated 

 in Diobsud Creek, a tributary of the Skagit River, as a check on the 

 extensive marking experiments of 1934 in that system. The first 

 returns from these experiments are expected in the fall of 1936. 



In order to have a complete understanding of the fishery problems 

 of the Columbia River system, it has been necessary to do a consid- 

 erable amount of research on the history and development of these 

 fisheries, and on the development and utilization of other natural 

 resources such as water power, agricultural land, and forests which 

 have influenced the fish populations by bringing about changes in 



