I'hoto by Shirley C. Ilulse 
SALOMON LE;aPING OVER THE SWIFT WATER NEAR THE TOE OF CAZADERO DAM AND SEEN 
FROM ABOVE 
destroyed by predaceoiis fishes and other 
agencies ; and, while the newly hatched 
young are in the helpless non-swimming 
stage, burdened by the heavy yolk-sac, 
they are such easy victims and such 
dainty morsels to the myriads of fishes 
that infest the spawning grounds, that 
an additional loss of lo to 15 per cent 
occurs, so that of the original crop of 
eggs, only I to 2 per cent reach the age 
to which the fish culturist carries the 
young salmon. 
Under the present effective methods 
■of artificial hatching, the total losses up 
to the time when the young are set free 
in the rivers, amply able to care for 
themselves, although still liable to con- 
siderable mortality before reaching the 
ocean, are not more than 20 per cent, are 
frequently only 10 per cent, and should 
not exceed 15 per cent under average 
conditions. 
Therefore, as against an absolute loss 
of 98 or 99 per cent in nature, the fish 
culturist is to be credited with a saving 
of 85 per cent. 
The natural mortality among young 
salmon in the rivers decreases rapidly as 
the fish become stronger, more active, 
and more alert. The most important ad- 
vance that salmon culture can make will 
therefore be in retaining the young at 
the hatcheries for a longer period before 
turning them loose in open waters to 
shift for themselves. There is no par- 
ticular difficulty in rearing salmon in 
captivity ; the difficulty lies in providing 
at a given hatchery the necessary arti- 
ficial pond area in which to hold and feed 
perhaps 100 million rapidly growing fish. 
EXTENT OF THE SALMON INDUSTRY 
The salmon industry on the Pacific 
coast owes its origin, rapid development, 
and present extent to the establishment 
of canneries. During the 50 years that 
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