Table 2.— Distribution of 1958 recoveries from days of tagging, Kviohak River system 



Day 



of 



tagging 



Recovery location and number 



-k 



1» 



§ & 



a 5 



9 10 11 12 13 15 16 17 18 19 20 21 22 24 25 26 27 28 29 30 



^ Recoveries in part or in whole known to be from personal-use fisheries, 



2 Does not include 14 tags recovered at or below Igiugig, and 1 after analysis was completed. 



fishing can influence fishing effort just as 

 they do in a commercial operation. Possible 

 variation in total recovery effort can be evalu- 

 ated however. Since personal-use fishing is 

 the principal source of recoveries, total effort 

 and personal-use effort will be similarly dis- 

 tributed. If the chronological order of passage 

 is maintained at personal-use fishing loca- 

 tions, and there is inequality in effort, different 

 periods of tagging will yield different recovery 

 percentages. For instance, if fish tagged in 

 two consecutive periods pass up the lake as 

 units and several days apart, a fishery oper- 

 ating when the first unit passes but not when 

 the second passes may produce tags from the 

 first period's tagging but cannot produce tags 

 from the second. Clearly the percentages 

 recovered from each unit cannot be the same, 

 under such conditions. 



In table 4, the fish tagged and tags recovered 

 are shown as total numbers and percentages 

 each year. Further breakdown within years 

 shows the number of tags by experiment and 

 the tagged and recovered fish in each experi- 

 ment as a percentage of the seasonal total. 

 Apparently the percentage of total tagged in 

 each experiment each year was remarkably 

 close to the percentage of total recovered in 



each. On the basis of these somewhat similar 

 percentages, it would appear that the effort 

 in personal-use fisheries was quite evenly 

 distributed over all of the groups tagged during 

 the years studied. 



One may also be concerned about variation 

 in fishing effort if the chronological order of 

 passage was not maintained at personal-use 

 fishing sites. In that event the effect would 

 not be detected but it is inconsequential, 

 since the analysis for extent of segregation 

 would not then be biased by a changing fishing 

 intensity. Complete intermixture would result 

 in a random exposure of all tags to any pattern 

 of fish effort. 



It appears that, despite the hazards of un- 

 limited utilization of personal-use recoveries, 

 they should not have introduced troublesome 

 errors in the analysis. 



Visual Comparison at All Recovery 

 Points 



Recoveries are plotted for the 3 years on 

 figures 5, 6, and 7 to illustrate the overall 

 pattern of distribution each year. The exact 

 locations of the recovery points are shown in 

 figure 8. 



12 



