THE GERMAN CARP IN THE UNITED STATES. 595 
than from definite information. It is a noticeable fact that this senti- 
ment is much less general, or may be largely replaced by one almost 
as unreasoning in favor of the carp’s entire harmlessness, in regions 
where this fish is commercially valuable on a large scale. The charges 
may-in a general way be divided into four i dee (1) That carp eat 
the spawn of other fish; (2) that carp eat the young of other fish; (3) 
that carp prevent the nesting of such fish as the basses; (4) that carp 
produce unfavorable conditions—chiefly roiliness of the water—that 
drive other fish away. 
In the Great Lakes region the fishes that are generally conceded to 
be in most danger from the carp are the bass and other members of 
the same family (crappie, sun-fish, bluegill), and the white-fish. It is 
obvious that they can hardly affect directly such other commercial and 
game fishes as the wall-eyed pike and sauger (St7zostedion, commonly 
called ‘‘ pickerel” on the Great Lakes), or perch” (Perca jlavescens), or 
trout; nor do I know of specific complaints of damage to the herring 
' (Argyrosomus), sturgeon, or the true pikes (Ksocide, ‘‘pickerel” of 
the inland waters). Most of these do not lay their eggs where they 
are likely to be troubled by carp, and some are probably considered 
able to take care of themselves. Still it seems that carp might easily 
affect wall-eyed pike, in cases where the eggs are attached to water 
plants; and if they affect white-fish they probably also affect herring, 
whose eggs are laid at the same time and presumably in the same places. 
The first of the complaints enumerated above, viz, that carp eat the 
spawn of other fish, is perhaps the one that has been most persistently 
maintained. One can scarcely read a communication by one of the 
opponents of the carp without finding in it a statement to that effect. 
Nevertheless, few, if any, direct observations are recorded. The argu- 
ment is something like this: Other fish, such as the bass, are decreas- 
ing, while the number of carp is, or at any rate has been, steadily on 
the increase; carp will eat practically anything; therefore, oli decrease 
of certain other fish must be due in large part to the fact ik the carp 
devour their spawn. What I wish to point out is that while the two 
‘emises may be true, the conclusion is by no means a necessary one. 
It can not be deduced from the above premises without other facts, 
and those facts have not been supplied. They might be of two kinds— 
first, direct observation of the eating of the spawn of other fish by 
oEys and, second, by the finding of the spawn of oben fish in the 
a With regard to the ie, at ihe thirtieth annual ane of the American Fisheries Society both 
Mr. Dickerson, of Detroit, and Doctor Parker, of Grand Rapids, Mich., expressed their opinion that the 
carp is indirectly harmful to the perch through oe destruction of the vegetation. Doctor Parker 
remarks (Transactions of the Society, 1901, p. 124): ‘‘ You must go back to the vegetable for the reha- 
bilitation of waters. If you destroy vegetation and the lary, you destroy the minnows, and the 
perch have no minnows to feed on, unless they can eat the young of the carp, which they do not 
appear todo, but the black bass will eat the young of the carp and will thrive. Therefore you may 
look for an increase of the black bass, a decrease of the minnows, and also of those fish that feed upon 
the smaller minnows.” 
