Biological Survey — Erie-Xiagaka Watershed 33 



bers. Judg'iiig' from temperatures recorded and from the observed 

 distribution of both species of trout, the upper 5.5 miles and tribu- 

 taries 3 (Eddyville), 4 (Spring run), 6, 7 and 10 are suitable for 

 brook trout. The lower 2 miles together with tributaries 1, 2 and 

 9 (Goodell) are generally too warm for brook trout and now con- 

 tain browns. In fact brown trout range everywhere except pos- 

 sibly in the coldest spring tributaries. The two species are so 

 thoroughly mixed that it is diiftcult to decide upon a proper stock- 

 ing policy. AVe feel that the planting of both sj^ecies in their 

 respective sections will best meet the situation and this recommen- 

 dation is founded on the belief that so far as possible, all parts 

 of a stream or system should be fully utilized and that we should 

 try to preserve brook trout in all fishing waters which show favor- 

 able conditions. 



In tributary IL, brook trout are abundant while browns are 

 scarce excepting in the last pool or two. The stream is supplied 

 chiefly from a spring which flows an 8 inch pipe full of water 

 having a temperature of 48.2"^ F. Temperatures near the mouth 

 of the stream 2:10 p. m., August 28 were, air, 85.5 and water 64; 

 one-half mile upstream at 2 :30 p. m., air, Sd.d, Avater 61. These 

 are among the lowest stream temperatures observed for the cor- 

 responding air temperatures and indicate that this stream is much 

 better adapted to brook trout than to browns. 



Analysis of the water in the spring itself showed 4.2 p. p.m. of 

 oxygen and 9.7 p. p.m. of carbon dioxide. These are well within 

 the limits endured by trout but nevertheless cannot be considered 

 highly favorable. Undoubtedly the water soon picks up enough 

 oxygen and loses enough carbon dioxide to make it entirely favor- 

 able. It will su];)]iort a relatively large number of brook trout and 

 should ap])eal strongly to the fisherman who prefers this species. 



A Proposed Artificial Lal-e for the Zoar Y alley: Because of its 

 bearing upon the stocking policy of certain streams tributary to 

 the main Cattaraugus creek, it is well at this time to mention the 

 proposed construction of a dam across the creek at a place .just 

 below tributary 2 (Watermans brook*). It is understood that this 

 may exceed 150 feet in height raising the water level to the 1,100 

 foot contour thereby flooding the Zoar valley upstream to the 

 Scoby bridge. A lake 8 to 9 miles long and in places a mile or 

 more wide may thus be formed. Considerably more than one-half 

 of this lake will exceed 100 feet in depth but there will be numer- 

 ous shallow bays extending up the valleys of tributary streams. 

 Immediately above the proposed lake at Scoby bridge there is now 

 a 30-foot dam impassable to fish. 



While it is impossible to predict just what conditions may pre- 

 vail, it is reasonably safe to assume the following : 



1. That the water below a depth of about 60 feet will be cold 

 enough for trout. 



* See Map 4B. 



