z 

 o 



< 



a 



z 

 < 



a. 



3 

 O 



q: 



03 



Z 



o 



s 



<3 



1963 



D FALL MIGRATION INTO RESERVOIR 



E SPRING MIGRATION INTO RESERVOIR 



El COMBINED MIGRATION FROM RESERVOIR 



SEP. 



OCT 



NOV. 



DEC. 



JAN. 



FEB. 



MAR. 



APR. 



MAY 



JUN. 



Figure 10. — Percentage of total catches of juvenile spring chlnook salmon from Eagle Greek that entered and that left 

 B^o^vnlee Resen'oir in different months, 1962-64. Fish entering the reservoir were caught in a louver trap at Eagle 

 Greek (Krcma and Raleigh, 1970) ; fish leaving the reservoir were caught in skimmer net traps in tie forebay 

 (1963) or in scoop traps below the dam (1964). 



10 20 

 JAN. 



9 19 



FEB. 



10 20 30 



MAR. 



19 29 



APR. 



19 29 

 MAY 



JUN. 



Figure 11. — Date of arrival at Brownlee Dam of juvenile spring chinook salmon tagged at 

 Eagle Greek during the fall and spring migrations of 1962-64. Each circle represents 

 one recovery. 



showed that juvenile fall cliinook salmon passed 

 through the reservoir in about 2 weeks in 1962 and 

 in about 7 weeks in 1963 (fig. 12). Figures 4 and 5 

 indicate that the currents would have been of low 

 velocity but moderately well oriented downstream 

 during the 1962 migration. In 1963, the migrant 



fall chinook salmon entered the reservoir a week 

 later than in 1962 (fig. 12). At that time the reser- 

 voir was drawn down only 3 m. and was being 

 filled. Although volumes of inflow and outflow 

 were moderate to high, the currents were disori- 

 ented (figs. 4 and 5). 



232 



U.S. FISH AND WILDLIFE SERVICE 



