The spawning period of summer chinook is 

 later in the season than that of the spring 

 Chinook and ranges from early October to 

 November . 



Blueback salmon spawn mostly in the 

 White Eind Little Wenatchee Rivers, both 

 tributaries of Lake Wenatchee. Other spawn- 

 ing areas are in Nason Creek and in the 

 Wenatchee River at the outlet of the lake. 

 Comparatively few blueback salmon are found 

 in Nason Creek. Live counts have totaled 

 under 100 fish in the three years of surveys. 

 However, counts taken in 1954 totaled around 

 550 blueback for this strecun. The number 

 of spawners at the outlet of the lake varies 

 greatly with the year. Peak survey counts 

 were less than 25 fish in 1955 and 1956 and 

 nearly 900 in 1957. 



YOUNG FISH MIGRATION 



In planning for the perpetuation of 

 anadromous species above power dams it is 

 just as important to have a knowledge of 

 the downstream migration phase of the life 

 cycle of the species as the upstream migra- 

 tion and spawning phases. Therefore, to 

 add to our knowledge of the anadromous runs 

 in the Wenatchee River system, studies were 

 made on the timing and intensity of the 

 downstream migration of young fish and their 

 length and age composition. 



Migration of young salmon and steel- 

 head was already under way when funds for 

 the studies were appropriated in the spring 

 of 1955. Therefore it was necessary to 

 locate a sampling station immediately and 

 to devise means of catching young migrants. 

 Turawater Dam, located a short distance down- 

 stream from a possible dam site in Tmnwater 

 Canyon proved an opportune place for sam- 

 pling the downstream migration. Here, a 

 substantial portion of the flow of the We- 

 natchee River was diverted through a large 

 tube to a power plaint located two miles 

 downstream. Young fish were screened from 

 this tube by means of large Link Belt 

 Screens and returned to the river through a 

 bypass channel. Trapping and counting the 

 young fish in this bypjiss was the method 

 employed to sample the downstream migration. 

 No attempts were made to determine the total 

 numbers of downstream migrants. 



In order to trap and count these mi- 

 grants passing down the bypass, a vertical 



illway of Oom 



Fingerling byposs 



Figure 9. — Fingerling bypass at Turawater 

 Dam and trapping device. 



