Fig, 3. A typical stretch of fast water in Bear 

 Trap Canyon. Alternate riffles and deep 

 holes in this stretch of the river pro- 

 vide conditions suitable to both rainbow 

 and brown trout. (Photo by L. E. Hiner). 



springs and seeps in that area. Temperatures cited above may be 

 considered to be below optimum for the development of rainbow 

 and brown trout (Needham 1938); however, growth studies of rain- 

 bow trout taken from the Madison River indicate a rate equal to 

 or better than most Montana streams (Montana State College, un- 

 published data). 



Chemical analysis of water from two locations in the 

 Middle Section indicate that it is medium hard and slightly 

 alkaline (Appendix A). Small amounts of domestic and industrial 

 pollution occur at a few points on the river but adverse effects 

 were not apparent. Physical pollution in the form of silt was 

 negligible. 



