after the lock was drained. The time required 

 to drain the lock was not included in the cir- 

 cuit time. Since the fish entered the fishway 

 at pool 3, passage times for pools 1 and 2 were 

 not obtained for the first circuit. Pool times 

 obtained as the fish began the seventh circuit 

 were substituted for these missing values in 

 the first circuit. 



Observations of Fish in Viewing Pool 



Each time a fish approached pool 13, two ob- 

 servers descended into the observation cham- 

 ber adjoining the fishway and recorded its 

 movements with respect to its position in the 

 pool. For standard observations, the pool was 

 arbitrarily divided into four equal quadrants. 

 A record of the elapsed time spent in each 

 quadrant was transmitted to the time-event 

 recorder by switch buttons. A separate button 

 for each quadrant enabled the two observers to 

 plot sequentially the pathof movement and time 

 spent in each part of the pool. The respective 

 switch buttons were depressed for the period 

 the fish remained in a particular quadrant. 

 When a fish was not visible, no button was 

 pressed, but the elapsed time (for the un- 

 observed period) was nevertheless maintained 

 by notation of the time between observed 

 movements. 



EFFECTS OF PLUNGING AND 

 STREAMING FLOW 



Effects on performance and behavior were 

 evaluated by comparing passages of individual 

 fish in alternating plunging and streaming con- 

 ditions of flow. Eighteen fish were tested; each 

 fish ascended 48 pools under each condition of 

 flow. 



Effect on Performance 



Comparison of performance in plunging and 

 streaming flows was based on (1) mean pas- 

 sage time per pool for all tests combined and 

 (2) passage time per circuit by individual per- 

 formance. 



Passage time per pool .-- Mean times per 

 pool (table 1) were first examined to determine 

 if perfornnance differed greatly under the two 

 conditions of flow. The total time for ascent of 

 16 pools was about 5 minutes longer in str cann- 

 ing flow than in plunging flow. Inspection of 

 passage time by individual pools (fig. 5), how- 

 ever, indicated that this difference was largely 

 the result of performance in pool 2, where 

 flows were changed after the fish completed 

 each circuit. Apparently the change of flows 

 from plunging to streanning detained the fish 



TABLE 1. — Mean passage times per pool in plunging and streaming 



flows; based on combined data from performance tests of 18 Chinook 

 salmon ascending a 16-pool, l-on-16 slope fishway 



Total 26.9 



(per circuit-- 

 16 pools) 



32.0 



5.1 



_!/ Streaming less plunging. 



