The leading edge moved at rates of 9.1 to 33.4 miles 

 per day and averaged about 18 miles per day, and the 

 center of density moved at rates of 1.0 to 15.4 miles 

 per day and averaged about 8 miles per day. In 1942 

 both of these measures of rate of travel for tagged fish 

 were considerably lower than in 1941. 



Weekly rates of survival and exploitation were 

 calculated for 30 experiments which had sufficient 

 numbers of recoveries adequately distributed in time. 

 For these experiments the average weekly survival 

 rate is 39.4^r and the average weekly exploitation rate 

 is 25.0%. A comparison of the exponential fishing rate 

 of 0.514 with the exponential other-loss rate of 0.595 

 indicates that the rate of removal of tagged fish by the 

 fishery was slightly less than the rate of removal from 

 all other causes combined. The estimates of exponen- 

 tial fishing rates were considerably lower than es- 

 timates obtained from tagging experiments in Icy 

 Strait in 1950. Part of the discrepancy between the es- 

 timated fishing rates in 1950 and in the earlier years 

 appears to be the result of incomplete detection and 

 reporting of recaptured tags in the earlier ex- 

 periments. 



A computer program that calculates the total rate 

 of exploitation on a run of salmon when recuitment, 

 outmigration, and fishing occur simultaneously was 

 used to estimate the fraction of the total run removed 

 by the fishery in 1938, 1939, 1941, and 1942. The tim- 

 ing of the entry of pink salmon into the fishing ground 

 was determined from an analysis of the catch data. 

 The average rate of exploitation on the total run dur- 

 ing the years included in this analysis is between 32% 

 and 51%. The exact figure cannot be estimated 

 without further knowledge of the extent of incomplete 

 reporting and tag loss. 



A series of recommendations for designing future 

 tagging experiments is presented. It is suggested that 

 the planning and design of tagging experiments could 

 be improved significantly by first simulating the ex- 

 periments on an open-ended digital computer simula- 

 tion model of the pink salmon fishery in southeastern 

 Alaska. 



ACKNOWLEDGMENTS 



It is a pleasure to acknowledge three persons who 

 contributed substantially to the preparation of this 

 manuscript. Sandra Anderson edited an early draft of 

 the report and carried out many of the numerical 

 calculations; much of the section on migration rates is 



based on her ideas. Jerry Jaffee and Lawrence Gales 

 wrote the computer programs used to process the 

 tagging data. 



LITERATURE CITED 



DAVIDSON, F. A., and L. S. CHRISTEY. 



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 ELLING, C. H., and P. T. MACY. 



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 FISHER, R. A. 



1950. Statistical methods for research workers. 11th ed., rev. 

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1927. Salmon-tagging experiments in Alaska, 1924 and 1925. 

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1938. The significance of the difference between two means 

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