Methods of Fish Culture. 7 
In trying these different methods more or less trout 
would die; but having always kept a hatching-house re- 
cord, I can give you the benefit of my experience in regard 
to the percentage of trout generally, raised with good care 
to six months old, one year old, and of trout brought to ma- 
turity from the time of taking the spawn—calling the age of 
maturity when the fish are old enough to spawn. 
We will say that you take from good, healthy fish one 
hundred thousand eggs. With a good, fair impregnation you 
will be likely to have from 80 to 85 per cent. impregnated 
(though you may take ten or twenty thousand, and perhaps 
impregnate from 95 to gg per cent). Out of these impreg- 
nated eggs you will find about five per cent. that have not 
strength enough to burst the shell of the egg, or die in get- 
ting out of the shell. This leaves you from 75 to 80 per 
cent. hatched. Before the sac is absorbed you will pick out 
about five per cent. more of dead fish from blue swelling of 
the sac and various other causes. By the time the fish 
have been feeding six weeks or two months you will have 
picked out twenty per cent. more of them from disease and. 
cannibalism. By this time they are ready to turn out, though 
if you-keep them in the hatching-house a month longer you 
will not be likely to lose many more. Now you have fifty 
per cent. left. After you have turned them out, and the fish 
are four months old, from 10 to 15 per cent. more will have 
died from starvation, cannibalism, disease, snakes, frogs, and 
birds. At six months old the fish have dwindled down to 
about 30 per cent. of your original hundred thousand eggs. 
The next six months, if you have them well. sorted, you 
will not lose more than from 3 to 5 per cent. Therefore, 
at one year from the time the eggs were taken, 25 per 
cent. of the products are left. At maturity from 15 to 20 
