Salmonidz 81 
salmon, ascend streams but a short distance before spawning. 
They seem to be in great anxiety to find fresh water, and many 
of them work their way up little brooks only a few inches deep, 
where they perish miserably, floundering about on the stones. 
Every stream of whatever kind, from San Francisco to Bering 
Sea, has more or less of these fall salmon. 
The absence of the fine spring salmon in the streams of 
Japan is the cause of the relative unimportance of the river 
fisheries of the northern island of Japan, Hokkaido. It is 
not likely that either the quinnat or the red salmon can be 
introduced into these rivers, as they have no snow-fed streams, 
and few of them pass through lakes which are not shut off by 
waterfalls. For the same reason neither of these species is 
likely to become naturalized in the waters of our Eastern States, 
though it is worth while to bring the red salmon to the St. 
Lawrence. The silver salmon, already abundant in Japan, 
should thrive in the rivers and bays of New England. 
The Parent-stream Theory.—It has been generally accepted 
as unquestioned by packers and fishermen that salmon return 
to spawn to the very stream in which they were hatched. As 
early as 1880 the present writer placed on record his opinion 
that this theory was unsound. In a general way most salmon 
return to the parent stream, because when in the sea the parent 
stream is the one most easily reached. The channels and run- 
ways which directed their course to the sea may influence their 
return trip in the same fashion. When the salmon is mature 
it seeks fresh water. Other things being equal, about the same 
number will run each year in the same channel. With all this, 
we find some curious facts. Certain streams will have a run 
of exceptionally large or exceptionally small red salmon, The 
time of the run bears some relation to the length of the stream: 
those who have farthest to go start earliest. The time of running 
bears also a relation to the temperature of the spawning grounds: 
where the waters cool off earliest the fish run soonest. 
The supposed evidence in favor of the parent-stream theory 
may be considered under three heads: * (1) Distinctive runs in 
* See an excellent article by H. S. Davis in the Pacific Fisherman for July, 
1903. t 
11—6 
