ASSORTING BROOD BLACK BASS TO PREVENT 
CANNIBALISM. 
IBS tis Jie SLE RZAUN ACEEASN 
Experience has taught at Cold Spring Station, Bureau of 
Fisheries, that there are in all our ponds individual large mouth 
black bass which are specially cannibalistic and it is the inten- 
tion of the writer to remove all such in future as fast as dis- 
covered, even resorting to the rifle to get them when necessary. 
But he believes that all large mouth black bass, and presumably 
small mouths also, should be assorted into the ponds in as near- 
ly the same sizes as is practicable, the large ones into the larger 
ponds and so on, it being desirable, where that number of ponds 
is available, to make them up into at least four or five grades. 
The larger bass are necessarily more logy and less active in 
their movements and therefore unable to protect their young 
from the raids of the smaller and more active individuals. They 
are also much less prone to cannibalism, in fact it is a rare oc- 
currence to see a bass weighing four or five pounds or more feed- 
ing on the fry in our ponds. 
When the smaller fishes are by themselves all are equally 
active and a one-pound male will defend his brood so vigorously 
that even the specially voracious individual soon finds that he 
can not run amuck among the fry at pleasure without suffering 
the consequences and cannibalism is reduced to a minimum even 
among the smaller and more bloodthirsty classes. 
Of course, a station must keep up its brood stock by either 
raising a supply from year to year or by introducing wild stock 
and by this system of sorting this growing stock can be made 
useful from two years old and later, while, in our opinion they 
would be far better kept by themselves and not reproduce at all 
than to place them with the larger fishes. 
It has sometimes been argued that such assorting as above 
recommended will result in a disproportion of the sexes. We do 
not believe that this argument is tenable. We have observed 
some of our largest bass this season guarding nests and pro- 
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