588 EEPORT OF THE COMMISSIONER OF FISHERIES. 



no wild celery, but do have much wild rice. Since the carp have been 

 planted, however, this has been largely rooted out; "they dig it up 

 like a drove of hogs, and have about spoiled the marshes for ducks." 

 Mr. C. J. Dregman, of Holland, writes that carp are abundant in 

 the lake (Black) and river there, and adds: 



As to their destructiveness to wild celery or otherwise I have no reliable informa- 

 tion to give you. There is comparatively little wild celery here, and that which 

 does grow here seems not to be affected from year to year. Common report has it, 

 however, that carp are destructive to fish eggs and nests. 



Mr. George C. Monroe, of South Haven, does "not believe they 

 cause any damage to plants along the river bank." At Muskegon, 

 according to Mr. E. D. Magoon, "the marsh is full of channels and 

 ba3'^ous, and these abound with carp." Wild celery, rice, and other 

 duck food are found here, but he expresses no opinion as to the effect 

 of the carp on these. 



Considerable valuable testimony on the question under discussion is 

 given b}^ Doctor Smith in his report on the acclimatization of fish in 

 the Pacific States (Smith, 1896, pp. 398-103). Several cases are men- 

 tioned where carp are reported as destroying ihe vegetation, most 

 notable among which are observations made at what are known as the 

 "Suisun Marshes." Doctor Smith (p. 397) quotes a letter from Mr. 

 Ramon E. Wilson, secretary of the California Fish Commission, dated 

 November 12, 1891, which states that certain portions of the marshes 

 referred to above have been preserved \)y five shooting clubs for a 

 period of ten years previousl3^ The letter continues: 



Each of these clubs has, from year to year, supplemented the natural and indigenous 

 growth of vegetation by planting non-indigenous seeds and grasses, until about two 

 years ago the ponds, ditches, and sloughs had so grown up with vegetable matter 

 that upon the opening of the season it was almost impossible to push a boat through 

 the dense growth. Last year, the season of 1890, it was discovered that a marked 

 change had taken place. The cause was attributed to the winter, which was a rather 

 severe one, in that there were many overflows and freshets occasioned by heavy 

 storms. This year the change in the respect mentioned was much greater. It was 

 early reported in the spring that there was very little sign of vegetable growth in any 

 of the ponds. Investigation followed, and it was found that fish in large numbers, 

 ranging from a few inches in length to 15 pounds in weight, had invaded the grounds 

 and taken entire possession of all the waters. These fish came, say, in May and 

 remained until about thelatter part of July — that is, the bulk, but many remained later. 

 We are convinced that these great numbers came to spawn. About August this great 

 school, if you can so call it, suddenly disappeared — that is, the larger ones and the 

 majority of the whole. Their going was not unlike the grasshopper in effect on vege- 

 tation — not a sign or remnant was left. The result i.s that to-day, where these same 

 ponds have heretofore afforded unlimited food supply for surface-feeding ducks in the 

 early part of the season and a like supply of celery bulbs for the canvasbacks and 

 redheads for the balance of the season, there is absolutely not a single sign of vegeta- 

 tion. At the time mentioned I carefully examined the beds of the ponds and found 

 them positively barren of vegetable matter. Notwithstanding the emigration, if it can 

 be so called, of the larger fish, the waters are still alive with the same fish, ranging 

 from 2 to 8 inches in length. These ponds, heretofore quite clear, are now nothing 



