Biological Survey — Genesee River 19 



75 on the hottest days; rapid current, without pollution, oxygen 

 nearly to the jioint of saturation at the higher temperatures. 



Examples of class (a) streams: Caledonia creek. Upper Trout 

 brook (tributary to Wiscoy), Hovey's brook (Map 3), Fulmer 

 valley brook. Cold brook, and parts of Ford, Orebed and Red 

 Water creeks (Map 5). 



Examples of class (b) streams: Dugan's and Macy brooks 

 (Map 2), Canaseraga at source, Bradner, Wiscoy and East Koy 

 (Map 3), Upi)er Rush creek (Maj) -1), Tapper Dyke, Cryder and 

 Marsh (Map 5). 



Brown Trout Waters. — With few excejitions brown trout were 

 found in every stream inhabited by brook trout. However, in the 

 colder brook trout streams, showing temperatures below^ 65, they 

 were rarely encountered. They reached maximum size and abun- 

 dance in streams ranging from about 68 to 75° F., and occurred 

 in many others attaining tem])eratures as high as 80° F. 



In Cryder creek (Maj) 5) tliey were found below the entry of 

 milk Avaste at Whitesville, in water the oxygen content of which 

 had dropped from about 6 to 4 parts per million. In the Wiscoy 

 at Bliss (Map 3) they were abundant and of large size, ranging 

 up into water polluted by milk waste. 



Thus we found them in streams w^hose conditions were tolerated 

 by brook trout and in others showing temperatures too high for 

 the latter. 



It has been ])ossible to extend the trout fishing range over many 

 miles of streams through the introduction of brown trout. Allen 

 creek from Buttermilk falls to its junction with Caledonia creek 

 l)robably would not offer trout fishing were it not for the intro- 

 duction of brown trout. The same is true for the lower sections 

 of Wiscoy and East Koy, Cryder below Wliitesville and Dyke 

 below Andover. In Dyke creek and tributaries there are about 

 11 miles suitable for brooks and 12 miles suitable for browns; 

 in Cryder 4.6 miles for brooks and 9 miles for browns. 



In the Genesee system, at least, it is not believed that brown 

 trout have had anything to do with diminishing the number of 

 brook trout in class (a) streams showing optimum conditions for 

 the latter. Consequently, in view of the probability of extending 

 the trout fishing range, we have consistently advocated the plant- 

 ing of brown trout in many streams that now contain brook trout. 

 However, we do not recommend brown trout for streams wdiich 

 have shown throughout their courses conditions favorable for 

 brook trout. 



Rainbow^ Trout Waters. — AVe have found rainbow trout in 

 warm streams where the temi)eratures range a little above 80 and 

 also in cold streams showing typical brook trout conditions. They 

 show a tendency to move down a stream to larger waters. This 

 movement takes place sometimes after the fish have reached a 

 length of 6 inches and before they have become sexually mature. 

 Apparently the adults remain in the larger streams and lakes, 

 except in spring, when there is an upstream migration to the 



