Biological Survey — Genesee River 17 



salinit}^ encountered here. But the fish food is particularly rich 

 therein, consisting of multitudes of salt fly maggots. 



Cryder creek, near Whitesville, and Wiscoy creek, near Bliss, 

 are polluted with milk wastes. The degree of pollution is not 

 great enough in either case to destroy brown trout and in the 

 latter case there is some indication that the fish food supply is 

 increased. However, it would be an easy matter to overload each 

 stream, thereby making them unsuitable for stocking. 



Size of Water. — Ordinarily the size of a stream bears more 

 directly upon the number and not the kind of fish to be planted. 

 In the case of warm streams, however, the size often determines 

 whether they shall be stocked at all. 



Streams that are too warm for trout may be either sluggish or 

 rapid. If sluggish they might be suitable for large-mouthed bass, 

 if rapid, for small-mouthed bass. However, small streams under 

 approximately 30 feet in width seldom furnish good bass fishing. 

 It is not definitely known why this is so. It seems reasonable to 

 believe, however, that the bass multiply to such an extent as to 

 exterminate the larger food animals — minnows, crayfish and 

 larger insect larvae — which leads to a degeneration in size. We 

 then have a stream populated largely with small bass four to seven 

 inches long, and the few that do grow to legal size are easily 

 cleaned out after the first few days of the open season. 



Many have assigned inbreeding as the cause of this degenera- 

 tion in size which is an easy way to avoid saying that we do not 

 know. To produce such a marked decline in size it would have 

 to be very close inbreeding, indeed, a possibility which is incon- 

 ceivable in wild waters. 



However, there is another possible factor operating here. As 

 bass approach legal size there may be a downstream movement 

 into larger waters where the forage is of better quality. If this 

 were true, it would account in a large measure for the scarcity of 

 legal sized bass in many small streams. 



Character of Bottom in Relation to Natural Spawning. — 

 Fishes vary widely in the selection of a suitable environment for 

 spawning. The small-mouthed bass prefer a clean gravel bottom 

 where there is a slight current. The large-mouthed bass may 

 select a bottom of sand or mud where such plants as the water 

 lily, cattail and others are rooted. A shallow depression formed 

 upon these roots may constitute the nest. If such an environment 

 is not available the nest Avill often be excavated in gravel. The 

 habits of the bluegill sunfish are similar to those of the large- 

 mouthed bass. The bullhead nests in the same general type of 

 environment but will take possession of a muskrat hole or exca- 

 vate its nest. 



The northern pike, muskalonge, carp and golden shiner scatter 

 their eggs over vegetation, while the yellow perch lays its egg- 

 string in such a way that it appears to be woven among the stalks 

 of aquatic plants, submerged branches, willow roots and the like. 

 However, these "strings" often lie on a barren bottom or may 

 sometimes float about in a vertical position buoyed up at one end. 



