The five times that dewatering of the fish- 

 ways at Rock Island Dam occurred in 1962 

 were as follows: 



1. Right fish ladder, from 8:00 a.m., 

 April 26, to 4:45 p.m., April 27, for routine 

 maintenance work. 



2. Left fish ladder, from 9:20 a.m. to 

 2:30 p.m., June 4, for repair of weir chains. 



3. Left fish ladder, from 10:50 a.m. to 

 12:30 p.m., August 1, shutoff of auxiliary water 

 to permit examination of fish ladder. 



4. Right fish ladder, from 12:00 noon to 

 3:40 p.m., October 4, for repairs to ladder 

 weirs. 



corded, representing 21 percent of that year's 

 total of chinook salmon counted. 



4. The sockeye count of 29,253, which ex- 

 ceeded the 1961 count by approximately 10,000 

 fish, was approximately 22,700 less than the 

 29-year mean of 51,920. 



5. Very few coho salmon have appeared at 

 Rock Island Dam in the period 1933-62. The 

 1962 count of 737 fish was more than three 

 times the previous high count of 229 in 1947. 



6. The steelhead count of 7,591 in 1962 was 

 almost two and one-half times greater than 

 the 29-year mean of 3,189 and was the highest 

 recorded in the period 1933-62. 



5. Left fish ladder, October 22, closed for 

 50 minutes in the afternoon to permit recovery 

 of items inadvertently dropped in fish ladder. 



Frequent inspections were made of fishway 

 operations by State and Federal personnel 

 throughout the counting season. From May 27 

 to 29, studies were made by fisheries person- 

 nel and members of Chelan County Public 

 Utility District of different spillway gate 

 operations. 



7. In 1962, a greater percentage of salmon 

 and steelhead utilized the left bank fish ladder 

 than used either the middle or right bank 

 ladders. 



8. Fish counting in 1962 began on May 1 

 and terminated October 27. From May 1 

 through September 13, fish were counted for 

 16 hours each day. From September 14 through 

 October 27, counting was reduced to conform 

 to the hours of daylight available. 



9. In 1962 the maximum number of salmonids 

 counted in 1 day (2,692) was on July 21. 



SUMMARY 



1. The total Rock Island Dam count of 

 salmon and steelhead in 1962 was 71,735, which 

 was approximately 12,300 more than the 1961 

 count. 



2. Annual counts of salmon and steelhead 

 passing Rock Island Dam during the period 

 1933-62, inclusive, are given in table 1. 



3. The chinook salmon count of 34,154 in 

 1962 was approximately 1,100 more than in 

 1961 and slightly more than one-half the peak 

 year of 1957. In 1962, 7,118 jacks were re- 



10. Season's total of fish other than salmon 

 and steelhead trout passing Rock Island Dam 

 in 1962 was 164,574 and was composed of the 

 following: sucker, 100,401; squawfish, 10,944: 

 whitefish, 38,309; chub, 10,105; carp, 1,756 

 shad, 1; Dolly Varden and rainbow trout, 61 

 and lamprey, 2,997. 



11. Of 71,735 fish examined, on the top 

 and one side only as they passed over the 

 counting boards, approximately 0.5 percent 

 had injuries of some type either on the body 

 or about the head. Greatest numbers of in jured 

 fish occurred in July and August. Injuries 

 were most numerous on large chinook and 

 sockeye salmon. 



