MIGRATION OF ADULT SOCKEYE SALMON. 33 
TABLE 22.—RaATE oF PROGRESS IN THE 19 CATEGORIES CONTAINING THE Most 
ELIABLE Data. 
Region Distance] Speci 
Ceoze peci- | Rate per 
Station marked, error: traveled.| mens. day. 
Miles. | Number.; Miles. 
i 12 12.5 
2 47.5 16 11.5 
6 60 23 10.5 
JSS) tet? apap AI a Sey en NALS ie 01 OE 9 ls Bee hg ae 7 71 32 6 VID. 
8 83 25 11.1 
9 92.5 13 12.8 
10 122.5 14 11.7 
6 21.5 25 9.3 
7 dood 35 7.6 
pened een er. kore etey NW ee. Ft ee Be bis) Sere’ 8 47.5 10.3- 
9 62 49 11.5 
10 92 54 14.6 
7 33 20 6.0 
C 8 45 48 8.3 
ithe Sts 3s Dee Hiaw SoTRn eS Be 9 59.5 28 9.1 
10 89.5 20 8.6 
D 9 27.5 109 10.2 
IIE TE Satan FA Gk aeaiaahe te  Wich airtel ilies orl toca 7 i mariage 10 bid 35 6.8 
Bene A een ae ee en ave eee A Gabe te Le ey Deas Me SSY 10 30 166 4.5 
Calculated from these figures the mean rate of migration is 7.8 miles 
per ae If the Canadian records are omitted, the rate is 9.7 miles 
per day. 
Greene,’ in his study of the migration of salmon (chinook, silver 
salmon, and steelhead) in the Columbia River, obtained results quite 
different from these. He estimates that from 30 to 40 days are 
usually required for the process of acclimatization to fresh water, 
during which time the fish work back and forth with the tides. After 
entering water which is wholly fresh he estimates the rate of travel 
of silver salmon and steelhead at 6.36 to 7.50 miles per day, although 
he concedes that this is only about one-third of the rate of travel as 
estimated by men engaged in the fishing industry and seems to imply 
that their figures are probably more reliable than his own. Greene’s. 
figures should be accepted with considerable caution on account of 
the comparatively few individuals marked and the fact that three 
species were represented and all combined to give his final results. 
The sockeye tagging experiment has produced no evidence indicating 
that the migration is especially retarded during the passage from salt 
to fresh water. As may be seen from Table 15, there is no great 
difference in the time required to pass from American waters to the 
Fraser River, just within the mouths, and that required to pass above 
New Westminister, where the water is entirely fresh. Furthermore, 
as will be seen later, in the case of fish taken on or near the spawning 
grounds in the tributaries, the time elapsed since marking averages 
between 30 and 40 days, the time given by Greene as required for the 
process of acclimatization. It may be concluded either that Greene’s 
results are wholly unreliable or that the migration of sockeye is quite 
different from that of the species studied by him, which is, of course, 
entirely possible. The rate of migration of the quinnat (chinook) 
‘salmon of the Sacramento River as given by Rutter ® is much more 
nearly in accord with the resultg of this sockeye study. He estimates 
‘loudsley: Natural history of the quinnat salmon. Bulletin U.S. Fish Commission for 
1902, Vol. XXII, pp. 65-142. Washington, 1903. 
