with a slippery brown film. 



Some algae, such as the filamentous greens, are conspicuous 

 and their excessive growth may be aesthetically displeasing, 

 deplete dissolved oxygen, interfere with fishing and fish 

 spawning, clog water filters and irrigation intakes, create 

 tastes and odors in drinking water, and cause other problems. 



PROJECT AREA AND SAMPLING SITES 



The project area is located in southern Park County in 

 southcentral Montana. Mill Creek and Pine Creek are east side 

 tributaries of the Yellowstone River that drain the Absaroka 

 Mountain Range (maximum elevation 11,206 feet) south of 

 Livingston. Pine Creek is a short (ca. 8 mi . ) , high gradient 

 second-order stream that begins at Pine Creek Lake in the 

 Absaroka-Beartooth Wilderness Area. Much of the upper watershed 

 is unroaded. Mill Creek is a longer (ca. 22 mi.), third-order 

 stream with a road running along most of its length. 



Tom Miner Creek enters the Yellowstone River from the west 

 about 16 miles north of Gardiner, Montana. The headwaters of Tom 

 Miner Creek are in the Gallatin Range (max. elevation 10,992 

 feet) just north of Yellowstone National Park. Tom Miner Creek 

 is a third order stream about 15 miles long with a road running 

 parallel to the stream along most of its length. 



All three creeks head in the Middle Rockies Ecoregion of 

 North America; the very lowest reaches of these streams pass 

 through the Montana Valley and Foothill Prairies Ecoregion (Woods 

 et al . 1999) . The surface geology of the watersheds consists 

 mainly of volcanic rocks of Tertiary age and undifferentiated 

 metamorphic rocks of Precambrian age (Renfro and Feray 1972) . 

 Vegetation is alpine tundra at the highest elevations, mixed 



