had they been forced to remain below the 

 dams over summer." Temperatures in the 

 Sacramento River downstream from Shasta 

 Dam were not recorded in 1943, but they no 

 doubt were in the sixties and seventies in June 

 and July as recorded in 1939 at Redding. 

 Seymour (1956) and Hinze, Culver, and Rice 

 (1956) have shown that very low survival of 

 eggs is to be expected at temperatures above 

 about 580 F. 



Although 8,034 salmon were transferred to 

 Deer Creek and 4,048 to Battle Creek from 

 Keswick and Balls Ferry traps during 1944, 

 no winter-run fish were noted. Temperatures 

 of Shasta Reservoir releases into the Sacra- 

 mento River were 61° F. when first recorded 

 early in August 1944, possibly low enough to 

 permit survival of eggs deposited before July, 

 But oxygen deficiency, common to waters from 

 new reservoirs, and heavy-metal pollution 

 probably occurred in initial releases from the 

 new reservoir. Heavy-metal pollution was seen 

 to kill adult fish in November 1944. 



In March 1945, about 200 Chinook salmon, 

 assumed to be winter run, were trapped at 



Keswick and hauled to Deer Creek. Additional 

 winter-run fish may have been included among 

 the 252 Chinook salmon hauled from Keswick 

 during April through June, but it is unlikely 

 that any were among the 2,838 hauled from 

 Balls Ferry duringMay through August of 1945. 

 It is assumed that some, perhaps most, of the 

 winter run escaped being taken in the Keswick 

 traps in 1945. The temperature of the released 

 water from Shasta Reservoir did not exceed 

 55° F. until mid-September in 1945. Thus, any 

 winter run that escaped could have spawned in 

 the Sacramento River successfully. In 1946, 

 only 20 fish were trapped at Keswick Dam in 

 May and none prior to that month. Apparently, 

 the entire winter run of 1946 remained in the 

 hospitable waters of Sacramento River. 



The records of the salmon salvage work 

 conducted during the construction of Shasta and 

 Keswick Dams thus indicated that the winter- 

 run populations were small and were harshly 

 dealt with by construction conditions, par- 

 ticularly high water temperatures, and by the 

 salvage activities which placed emphasis on 

 saving the spring-run fish (table 1.). 



Table 1. — Winter-run Chinook salmon stocks blocked by Keswick Dam and water tem- 

 peratures of Sacramento River during June-July spawning periods of years 1943 

 through 1946 



^Assumed from data of 1939 at Redding. 

 Extrapolated from record of Shasta Dam release temperatures beginning August 2, 1944. 



