Table 2 . Summary of physical measurements and habitat conditions of Beaver Creek and 

 Little Beaver Creek, 1977. 



Table 3 . Summary of physical measurements and habitat conditions of lower 

 Yellowstone tributaries. 



Acfianeuila sp is the only species of stonefly collected in Beaver Creek 

 and its tributaries. The substrate and flow patterns of these creeks are not 

 conducive to stonefly development. Intermittence of the creek coupled with 

 sluggish current, shifting and mucky substrates are limiting this group. 

 Stoneflies are most successful in cobble and gravel substrates of permanent 

 streams (Hynes 1976). 



CaznU, sp and Catiibaetli sp are the two most widely distributed mayflies 

 in Beaver Creek. These two genera are tolerant of a wide variety of environmental 

 conditions but seem to prefer productive, slow moving waters. Cazrvii sp. and 

 CcdllbaeJM) sp. are the dominant mayflies in Sarpy Creek which is similar to 

 Beaver Creek in many respects (Clancey 1977). 



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