Changes in Bacterial Populations in Wyoming Mountain Streams After 10 Years

Abstract

Streams of mountain watersheds in Wyoming were monitored to compare water quality data collected during 1971-72 with data collected during 1982. After 10 years there was little change in: (1) total coliforms, (2) fecal coliforms, (3) fecal streptococci, (4) plate counts at 35 degrees C, (5) total heterotrophic aerobic bacteria, (6) denitrifying bacteria, and (7) those organisms capable of reducing sulfate. Grazing management, recreation activities, and wildlife use of the watershed studied seem to be contributing a constant bacterial load to streams sampled by year and month during summer.