OREGON (Cont. ) 



4. Enumeration of Runs of Salmonid Fishes in Snake River 



This study was undertaken to collect data on the time of migration and 

 numerical abundance of Snake River salmon and steelhead runs. 



Barrel -shaped fyke nets, as large as 18 feet long and 10 feet in diameter 

 were used to tag fish in the Snake River just below and above Lewiston, Idaho. 

 The nets were operated in two batteries, a lower one for tagging and an upper 

 battery for recovery of tagged fish. 



U. S. Army Corps of Engineers and Idaho Department of Fish and Game 

 cooperating; Lower Snake River; began 1953, to close July 1957; Edwin K. 

 Holmberg, Leader; reports available. 



Address inquiries to: Edwin K. Holmberg, Fish Commission Research 

 Laboratory, Route 1, Box 31A, Clackamas, Oregon. 



5. Downstream Migrant Salmonid Collecting at High Dams 



Fingerling collection by creation of surface currents will be tested and 

 evaluated at Lookout Point Reservoir on the Middle Willamette River during 

 the spring of 1957. The reservoir is typified by fluctuating water levels and 

 little or no spill. 



A large pump mounted on a floating platform and capable of discharging 

 50 cubic feet per second will be used to produce currents at various locations 

 along the spillway of the dam. Fish attracted to the device will be retained 

 by a trap mounted on the platform. Fingerlings now being held at a nearby 

 hatchery will be released in the reservoir when testing begins. 



U. S. Army Corps of Engineers cooperating; Lookout Point Reservoir; 

 begins springl957, indefinite; $73,000; Edwin K. Holmberg, Leader; reports 

 available. 



Address inquiries to: Edwin K. Holmberg, as in No. 4 above. 



6. Estimation of Adult Chinook Sainton Mortality at Bonneville Dam 



This study is an attempt to determine the number of adult Chinook salmon 

 killed in the vicinity of Bonneville Dam on the Columbia River. 



Dead salmon that had been kept in cold storage from the preceding spawn- 

 ing season were thawed, tagged, and introduced into the Columbia River at 

 various locations where mortalities might be expected to occur. A systematic 

 search of areas below Bonneville Dam was made to recover tagged carcasses 

 intermingled with untagged carcasses. 



U. S. Fish and Wildlife Service cooperating; Columbia River; began 

 April 1955, closed November 1956; Theodore R. Merrell, Leader. 



Address inquiries to: Melvin D. Collins, Fish Commission Research 

 Laboratory, Route 1, Box 31A, Clackamas, Oregon. 



7. Study of Effects of the Dalles Dam on Migration of Anadromous Fishes 



Salmonid fishes are being tagged at Bonneville Dam and released above 

 the dam to proceed upstream. Recovery of tagged fish at McNary Dam up- 

 river provides estimate of migration rate between two structures. Complete 

 closure of river at the Dalles Dam occurred in the fall of 1956. Tagging 

 will be repeated in 1957 for comparison of migration rate before and after 

 effects of the Dalles Dam might be felt. 



Fish for tagging were captured at upstream exit of Washington shore fish- 

 way at Bonneville in a specially designed floating trap. Approximately 9, 000 

 salmonids were tagged during field work in 1956. 



U. S. Army Corps of Engineers cooperating; Columbia River; began 

 May 1956, to close 1957; Theodore R. Merrell, Leader. 



Address inquiries to: Melvin D. Collins, as in No. 6 above. 



Ill 



