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 maj^ be largely replaced by one almost 

 as unreasoning in favor of the carp's entire harmlessness, in regions 

 where this fish is commercial!}' valuable on a large scale. The charges 

 may in a general way be divided into four headings: (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 wlrlce-fish. It is 

 obvious that they can hardly aft'ect directly such other commercial and 

 game fishes as the wall-e3^ed pike and sauger {StizostecUon, commonly 

 called " pickerel" on the Great Lakes), or perch « {Perca flavescens)^ or 

 trout; nor do I know of specific complaints of damage to the herring 

 {Argyrosomus), sturgeon, or the true pikes (Esocidse, "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, the decrease 

 of certain other fish must be due in large part to the fact that the carp 

 devour their spawn. What I wish to point out is that while the two 

 premises 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 

 carp; and, second, by the finding of the spawn of other fish in the 



a With regard to the perch, at the thirtieth annual meeting 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 the 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 larvae, 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 to do, 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." 



