AAA■^^^^A^ 



40 60 ^' 80 



Minutes After Release 



FIGURE 11.- PASSAGE PER MINUTE OVER WEIRS 54 55, 

 56, 57 AND 60 DURING CAPACITY TEST OF 

 SEPTEMBER 7, 1956. 



and 60 fish per minute. The average for the 

 17-ininute period was 51 fish per minute. 

 (Table 3, Appendix.) 



The fact that the entry rate in the 

 September 7 trial did not appreciably de- 

 cline after rising to a peak as was typical 

 in all previous tests, but instead rose to 

 and then sustained a maximum level for a 

 number of minute, leads us to believe that 

 we may have achieved a condition (maximum 

 entry) which might demonstrate the existence 

 of capacity. Since this was the only test 

 in which a sustained entry wzts demonstrated, 

 a conclusion regarding the foregoing must 

 await the conduct of further tests in which 

 conditions of maximum entry can again be 

 repeated for a sustained period. 



Pool Residence Per Minute , 

 September 7 Test 



Given in figure 12 are curves showing 

 the number of fish present in each of the 



10 20 30 40 50 60 70 80 90 100 110 120 

 Minutes After Release 



FIGURE 12. --NUMBERS OF FISH PRESENT IN POOLS 55, 

 56 AND 57 DURING A GIVEN MINUTE IN THE 

 SEPTEMBER 7, 1956 CAPACITY TEST. 



three lower pools (55, 56, and 57) in a 

 given minute during the September 7 capacity 

 test. During the test, it became evident 

 that fish were not moving through the fish- 

 way as rapidly as they had in previous tests. 

 For this reason, the usual 60-minute trial 

 period was extended for an additional hour 

 to allow for a continued observation of 

 movement in the fishway. The maximum number 

 of fish observed in a single pool in a given 

 minute was 239. This occurred in both pools 

 55 and 56, reaching a maximum in minute 35 

 in the former, and minute 21 in the latter. 

 The maximum number of fish in the fishway 

 (6 pools) was 948, reached 28 minutes after 

 release. (For complete data on the fore- 

 going, refer to table 4 in the Appendix.) 



A striking feature in the comparison 

 of pool residence in the three lower pools 

 is the continued long residence in pool 55, 

 the first pool in the fishway. After reach- 

 ing a peak of 239 fish in the 35th minute, 

 numbers present in this pool did not fall 

 below 200 fish until the 80th minute. By 

 contrast, residence in pools 56 and 57, 

 after reaching a peak density, declined far 

 more rapidly than in pool 55. At the con- 

 clusion of the 2-hour test a total of 82 

 fish remained in pools 56 and 57. Almost 

 double this number was present in pool 55 

 at the end of the test. 



15 



