MIGRATION OF ADULT SOCKEYE SALMON. 5 
TABLE 22.—RatTE oF PROGRESS IN THE 19 CATEGORIES CONTAINING THE Most 
RELIABLE Data. 


Region 


en . 7 Distance| Speci- | Rate per 
Station marked. , eetnare q, traveled. | mens. day. 
| Miles Number.; Miles. 
1 | 35 * 12 12.5 
2 47.5 16 11.5 
6 60 23 10.5 
7 ORIN 8 OCC BOBO Oe SL OS SEEGERS Se TE 2 See Ri ete ete 7 71 32 WA. 
8 83 25 11.1 
9 92.5 13 12. 8 
10 122.5 14 ne eg 
6 | 21.5 25 9.3 
7 33. 5 35 7.6 
ee SU ae eee oe cae eo ee A Ae Sad ated on BAA RR Te 8 47.5 56 10.3 
9 62 49 11.5 
10 92 54 14.6 
7 33 20 6.0 
C 8 45 48 8.3 
LRN et na Se Ot ae ad any hn ey ee gS iy eo a RGA pea a 9 59. 5 28 9.1 
10 89.5 20 8.6 
D 27.5 109 10.2 
RrSEe 7 EN bie DUAGL tas Tisch eek Bhd ON CORA EE tO RED TOL to 10 bev gati) 35 6.8 
LO ce Re ene Sag See ARIE (y= SRE See OEE tee Bene ae 10 30 166 4.5 


Calculated from these figures the mean rate of migration is 7.8 miles 
per day. 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 results of this sockeye study. He estimates 

a Greene, Charles W.: The migration of salmonin the Columbia River. Bulletin U. S. Bureau of Fish- 
eries for 1909, Vol. X XIX, pp. 129-148. Washington, 1911. 
+ Rutter, Cloudsley: Natural history of the quinnat salmon. Bulletin U.S. Fish Commission for 
1902, Vol, XXII, pp. 65-142. Washington, 1903. . 
