Project Area and Sampling Sites 



The project area is located within the Northern Rockies Ecoregion in Lincoln County, 

 Montana. The mountains and valleys of the Northern Rockies are covered by extensive 

 Douglas-fir and subalpine fir climax forests. Portions of it arc influenced by moist maritime air 

 masses and support Pacific Coast trees such as western hemlock and western redcedar. Alpine 

 areas occur but, as a whole, the region has lower elevations, less perennial snow and ice, and 

 fewer glacial lakes than the adjacent Canadian Rockies. Logging and mining are common and 

 have affected water quality. Recreational uses are also important (Woods et al. 1999). 



Periphyton samples were collected at three sites on the Yaak River and one site on the 

 West Fork of the Yaak River (Table 1). The Yaak River is a tributary of the Kootenai River 

 and occupies USGS HUC 17010103. Waters in the Yaak River basin are classified B-1 in the 

 Montana Surface Water Quality Standards. 



Methods 



Periphyton samples were collected following standard operating procedures of the 

 MDEQ Planning, Prevention, and Assistance Division. Using appropriate tools, microalgae 

 were scraped, brushed, or sucked from natural substrates in proportion to the importance of those 

 substrates at each study site. Macroalgae were picked by hand in proportion to their abundance 

 at each site. All collections of microalgae and macroalgae were pooled into a common container 

 and preserved with Lugol's (EKJ) solution. 



The samples were examined to estimate the relative abundance of cells and rank by 

 biovolume of diatoms and genera of soft (non-diatom) algae according to the method described 

 by Bahls (1993). Soft algae were identified using Smith (1950), Prescott (1962, 1978), John et 

 al. (2002), and Wehr and Sheath (2003). These books also served as references on the ecology 

 of the soft algae, along with Palmer (1969, 1977). 



