• 



# 



• 



Project Area and Sampling Sites 



The Swan River TMDL planning area is located within the Northern Rockies Ecoregion 

 of Montana (Woods et al. 1999) in Lake and Missoula counties. Vegetation is mainly mixed 

 conifer forest, with alpine tundra on the highest peaks (USDA 1976). The main land uses are 

 recreation, logging, and wildlife production. The study streams are all tributaries of the Swan 

 River (HUC 170 102 11), which heads in Gray Wolf Lake in the Mission Mountains, flows 

 northerly through Lindbergh Lake and Swan Lake, and then into Flathead Lake. Streams in the 

 Swan River drainage are classified B-1 in the Montana Surface Water Quality Standards. 



Periphyton samples were collected at 9 sites on 4 tributaries of the Swan River (Table 1). 

 Goat Creek heads on the west side of the Swan Range and flows westerly into the Swan River. 

 Elk Creek, Jim Creek and Piper Creek head on the east side of the Mission Range and flow 

 easterly into the Swan River. Sample sites are generally located between 3,000 and 4,000 feet 

 elevation. 



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

 and preserved with Lugol's (EKI) solution. 



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

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

 in 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 ( 1 969, 1 977). 



