scale, except for refugia. which is evaluated for the entire subpopulation. A combination of 

 qualitative and quantitative data, and local knowledge was used in conjunction with the rule-set 

 developed by the Lolo National Forest to evaluate the following indicators. 



Water Quality 



1) Temperature: Stream temperatures have been monitored for four years at two sites in Upper 

 Willow Creek. One site is located near the upper end of subwatershed -03 and the other is near 

 the lower end of subwatershed -01. Based on this data it appears that summer temperatures 

 commonly exceed 15°C (59°F) in portions of the watershed used as a migratory corridor and 

 exceed 10°C (50°?) in potential spawning habitat for bull trout. This indicator is functioning at 

 unacceptable risk in all four sub-watershed areas. 



2) Sediment: Measures of fine sediment are based on wolman pebble counts conducted during 

 R1/R4 habitat surveys and visual estimates during walkthrough surveys. The Forest Service 

 relied heavily on the LNF rule-set to assist with the decision in the subwatershed containing 

 substantial amount of private land. Moderate-to-high road densities and valley bottom 

 conversion to pasture lands, below the Forest boundary, in subwatersheds -02, -03 and -04 have 

 likely elevated fine sediment levels. This indicator is; functioning appropriately in subwatershed 

 -01, functioning at risk in subwatershed -02, and functioning at unacceptable risk in 

 subwatershed -03 and -04, and the Upper Willow Creek watershed as a whole. 



3) Chemical Contamination / Nutrients: Three streams, including Upper Willow Creek (-02, - 

 03, -04), Scotchmans Gulch and Miners Gulch (both in -04) were listed as WQLS on Montana's 

 1998 303(d) list. All of these waterbodies were determined to lack sufficient credible data to 

 support listing and were removed from the Year 2000 303(d) list. This indicator is functioning 

 appropriately in -01 and functioning at unacceptable risk in the other three subwatersheds and the 

 Upper Willow Creek watershed as a whole. 



Habitat Access 



4) Physical Barriers: Irrigation diversions are located at numerous points, on tributaries and 

 Upper Willow Creek in subwatersheds -02, -03 and -04. At least two of these (on tributaries in - 

 02) block fish passage at all flows. The status of others on private land are unknown. Based on 

 this, the Deerlodge rated this indicator is functioning at risk in all subwatersheds and for the 

 entire Upper Willow Creek drainage. 



Habitat Elements 



5) Substrate Embeddedness: Substrate embeddedness was not measured directly. Levels of fine 

 sediment were used to indicate levels of embeddedness. Measures of fine sediment were based 

 on wolman pebble counts conducted during R1/R4 habitat surveys and qualitatively assessed 

 during walkthrough and fish distribution surveys. The Deerlodge Forest relied heavily on the 

 LNF rule-set to assist with these determinations made for subwatersheds with substanUal amount 

 of private land. Moderate-to-high road densities and valley bottom conversion to pasture lands, 

 below the Forest boundary, in -02, -03 and -04 have likely elevated fine sediment levels. This 



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