MIGRATION OF ADULT SOCKEYE SALMON. 19 
marking done at this station during August so much under suspicion 
that it was considered necessary, in.certain phases of the study, to 
disregard entirely the returns. 
It is important to call attention to the fact that the figures given 
in Table 3 can not be accepted as giving any adequate idea of the 
percentage of fish entering from the ocean which are caught while 
passing through the waters where commercial fishing is permitted. 
Several indeterminate factors must modify the percentage of returns 
to such an extent that, while they are reasonably comparable inter se, 
the actual figures give a much-distorted idea of the toll taken from 
the run as it is passing through the Sound and river. Two of these 
factors are especially obvious, i. e.: (1) The figures as given here do 
not include all of the actual returns, since some were omitted on 
account of faulty or incomplete data; the error from this factor, 
however, is not great, apprommately 5 per cent; (2) a much more 
important source of error is due to lost tags. There are no means 
of knowing just how many were taken and not turned in. Nor can 
anything more be learned as to the number of tags lost from the 
fish between the time they were attached and the time the fish were 
captured. Numerous reliable reports came to us of fish that showed 
splits in the tail fins terminating in holes similar to the one made 
with the leather punch. Apparently the tags had in some manner 
become caught and pulled out. Another possibility is that some 
of the fish were unable to stand the operation necessary to the 
attachment of the tag, more particularly the attendant handling and 
removal from the water. 
All of these factors would tend to increase the percentage of fish 
captured, but obviously there are no means for determining to what 
extent. 
TABLE 3.—NUMBER OF FisH MARKED FacuH Day, Toran NUMBER OF RETURNS FROM 
Each Day’s MARKING, AND PERCENTAGES OF RETURNS FOR Eacu Station, 1918. 





Station A. Station B. Station C. 
eked R Percent- Re. __ | Percent- Re. | Percent- 
Marked. faced: pee si Marked. Garricst. pee a Marked. fanaa fetes 7 
Gully; 14 sags2s2edse22 a 1 Obit fil Sods tocks| Sect scene secretes ceseee-Ss|aecen Mclean en cen. 
eee ae ool aaa cial voces aewe| cia stenitnec] accimneicis «lecis's cis catalce ced occ 43 14 32 
LD eae eee nates ceen eoacelds «| secdacee| sateeinealdas casita tebiciae ae 50 19 38 
p) a eee ee 46 16 35 25 5 7A | [Steere Been mn emaee eee 
7 pa ih ss pt aba 10 4 40 40 10 25 61 16 26 
aos SRLS. -SS see 20 2 10 95 27 28ie¢ epee dee ag Sos else ceeds 
PA Sewenamasecd 8 1 12 56 18 32 76 25 33 
Cie a eee 56 4 7 50 13 26% “Pao 2232S Ss ste es eso. 
QO Secs scene we dl scone ct ocloesetanac decomacae ill 45 40 152 48 382 
Bhattedeavencooe 98 16 1 lasceatecs| cacesouee Sse ee ase ieeme saa cescats os |odcac es s.0 
QS. Fact ek Secs 72 15 21 54 27 BO peshs ooh toes en ot cerca | te Sen ct te 
BO Gao econ bets 99 20 20 17 3 Lem horace ssl asice acces |socadencs 
Dl Stee ea teases 105 24 23 48 20 CD Wea | ie tae) Ae eed eee ee 
7a ee 77 12 16 104 46 nel SAE ed Beane ae Geen 
L Sens eas 138 21 15 64 24 38 (ee Rag eae Se a eee ee 
ies ae ere 64 8} 12 94 44 iat wiht. cb sabe. bates astsesees 
Dod se aeactewes|sccscessclocdvawent|Seeeeedes 42 18 (Sho ol |Se4s83ee8 Baessep ad eee 
(ae ee 34 3 Oo foceccensa|coccectealnasareees 164 2 1 
(ee So ee ee ee ee 36 1l 31 118 14 12 
te apt Es Sar a rence cee co cmnee cel daneneccoldcccccoselseeoeatonlovsaasece 105 25 24 
13:1 . §suhee Hl eeeeeaee [SNe cee SEs eee A Canale San ee | es es 155 24 15 
14 cus eee eee ee ST tc eee eee 76 16 21 




