STATION NUMBERS 



2 4 6 8 10 12 14 16 18 20 



10 

 20 

 30- 

 40 

 50 

 60 

 70 

 80 



0- ? . ? . f . 6 8 10 12 , 14 ^ 16 18 20 



2 4 6 8 10 12 14 16 18 20 



MARCH 11-14 



Figure 6. — ^Water temperature profile and stratlflcatioQ cycle at Brownlee Reservoir, 1963, modified from Bbel 



and Koski (1968). 



Table l.—Estimaled numbers of juvenile spring chinook 

 salmon that entered Brownlee Reservoir, 196S-66 (from 

 Krcma and Raleigh, 1970) 



Welser River origin 



Eagle Creek origin 



Year 



Age- • 

 group I 



Spring migrants 



Age-group 

 I 



Fall migrants 

 Age-group 

 I 



Number Number Number Number Number Number 



1962 122,600 (>) (i) (>) 116,000 1,200 



1963 16,000 600 13,600 P) 7,600 (!) 



1984. 6,800 (!) 6,700 (!) (!) (l) 



1968 3,200 (!) (1) (!) (1) (1) 



 Not estimated. 



' Negligible numbers. 



Weiser River Population 



Spring chinook salmon from the Weiser River, 

 106 to 176 mm. long, entered the reservoir as 

 yearlings from early April until late June. The 

 migration peaked from late April to early May 

 each year. 



Through late May, spring chinook salmon from 

 the Weiser River that were in the reservoir could 

 be distinguished from fall chinook salmon of age- 

 groups O and I on the basis of length ; they were 

 longer than age-group O but shorter than age- 

 group I of the fall stock. After late May, as length 



226 



U.S. FISH AND WILDLIFE SERVICE 



