be standardized as much as possible around 

 these variables. 



SUMMARY AND CONCLUSIONS 



1. A cooperative researchprogram between 

 the Fish and Wildlife Service, the Forest 

 Service, and the Fisheries Research Insti- 

 tute to study effects of logging on salmon 

 streams in Alaska started in 1956. Part of 

 the program involved estimating abundance 

 and distribution of adult salmoninfive streams 

 in the HoUis area of Kasaan Bay, Southeastern 

 Alaska. 



2. Tests of variability of estimates of dif- 

 ferent observers and of the same observer 

 counting the sanne area more than once were 

 made in 1956 and 1957. Results showed that: 



a. In tests made under ideal field condi- 

 tions (riffles only), variability of estimates 

 of pink salmon (between different observers 

 and between successive counts made by the 

 same observer) was low. 



b. In tests conducted under normal 

 conditions (pools and riffles), variability 

 between observers counting salnnon in pools 

 was much higher. 



Therefore, it is suggested that periodic 

 counting be restricted to shallow riffle areas 

 so that an index of abundance can be obtained 

 by using a method such as Gangnnark and 

 Fulton's (1952). Further, counting should be 

 standardized around such variables as amount 

 of available light, stream levels, and others. 



ACKNOWLEDGMENTS 



I would like to acknowledge the assistance 

 of the following people: Donald E. Bevan, who 

 developed basic techniques to assess variabil- 

 ity of different observers in estinnates of 

 abundance of salmon on spawning grounds; 

 William F. Royce and Robert L. Burgner, who 

 made many helpful suggestions in preparation 

 of this manuscript; and Charles Junge, Jr., 

 who examined statistical treatment of data 

 and made suggestions. 



William J. McNeil, Donald Hansler, Thomas 

 Calkins, Donald Day, Donald Campbell, Walter 

 Vaux, Richard Tyler, Roger Meyers, and 

 Patrick McGunnigle were the observers. 



LITERATURE CITED 



BEVAN, DONALD E. 



1961. Variability in aerial counts of spawn- 

 ing salnnon. Journal of the Fisheries 

 Research Board of Canada, vol. 18, 

 no. 3, p. 337-348. 



GANGMARK, HAROLD A., and LEONARD A. 

 FULTON. 

 1952. Status of Colunnbia River blueback 

 salmon runs, 1951. U.S. Fish and Wild- 

 life Service, Special Scientific Report- - 

 Fisheries No. 74, 29 p. 



JAMES, GEORGE A. 



1956. The physical effect of logging on 

 salnnon streams of southeast Alaska. 

 U.S. Department of Agriculture, Forest 

 Service, Alaska Forest Research 

 Center, Station Paper No. 5, 49 p. 



MS #1139 



GPO 9 26 7 2B 



