Low V V V M (1-5%) Moderate M M HR M (6 25%) – High HR HR HR HR (>25%) South Fork Figure 4.4.2– . South Fork summer steelhead population risk ratings integrated across the four viable salmonid population (VSP) metrics. Viability Key: HV Highly Viable; V Viable; M Maintained; HR – – – – High Risk; Shaded cells does not meet viability criteria (darkest cells are at greatest risk). – Current Status Assessment Lolo Creek Summer Steelhead Population – The Lolo Creek summer steelhead population (Figure 4.4.3–1) is one of five populations within the Clearwater River MPG within the Snake River steelhead DPS. Figure 4.4.3– . Lolo Creek summer steelhead population boundary major (MaSA) and minor (MiSA) spawning areas. The Interior Columbia Technical Recovery Team (ICTRT) classified the Lolo Creek population as in size and complexity based on historical habitat potential (Table 4.4.3–1; ICTRT “basic” 2007). A steelhead population classified as basic has a mean minimum abundance threshold of 500 natural-origin spawners with sufficient intrinsic productivity to achieve a 5% or less risk (“low risk”) of extinction over a 100-year timeframe. Table 4.4.3– . Lolo Creek summer steelhead population basin statistics and intrinsic potential analysis summary. Drainage area (km2) 628 Stream lengths km (total) a 373 Stream lengths km (below natural barriers) a 284 Branched stream area weighted by intrinsic potential (km2) 0.461 Branched stream area km2 (weighted and temp. limited) b 0.461 stream area weighted by intrinsic potential (km2) 0.779 Total stream area weighted by intrinsic potential (km2) temp limited b 0.779 Size / Complexity category Basic / (trellis pattern) “C” Number of major spawning areas (MaSAs) 1 Number of minor spawning areas (MiSAs) 0 a. All stream segments 3.8m bankfull were included. ≥ b. Temperature limited areas were assessed by subtracting area where mean weekly modeled water temperature was > 22oC. Current Abundance and Productivity Current total abundance (number of adult spawners in natural production areas) is unknown for this population. The Lolo Creek population includes spawning and rearing habitats at two
Low (1-5%) V V V M Moderate (6 – 25%) M M M HR High (>25%) HR HR HR South Fork HR Figure 4.4.2– . South Fork summer steelhead population risk ratings integrated across the four viable salmonid population (VSP) metrics. Viability Key: HV – Highly Viable; V – Viable; M – Maintained; HR – High Risk; Shaded cells – does not meet viability criteria (darkest cells are at greatest risk). Current Status Assessment – Lolo Creek Summer Steelhead Population The Lolo Creek summer steelhead population (Figure 4.4.3–1) is one of five populations within the Clearwater River MPG within the Snake River steelhead DPS. Figure 4.4.3– . Lolo Creek summer steelhead population boundary major (MaSA) and minor (MiSA) spawning areas. The Interior Columbia Technical Recovery Team (ICTRT) classified the Lolo Creek population as “basic” in size and complexity based on historical habitat potential (Table 4.4.3–1; ICTRT 2007). A steelhead population classified as basic has a mean minimum abundance threshold of 500 natural-origin spawners with sufficient intrinsic productivity to achieve a 5% or less risk (“low risk”) of extinction over a 100-year timeframe. Table 4.4.3– . Lolo Creek summer steelhead population basin statistics and intrinsic potential analysis summary. Drainage area (km2) 628 Stream lengths km (total) a 373 Stream lengths km (below natural barriers) a 284 Branched stream area weighted by intrinsic potential (km2) 0.461 Branched stream area km2 (weighted and temp. limited) b 0.461 stream area weighted by intrinsic potential (km2) 0.779 Total stream area weighted by intrinsic potential (km2) temp limited b 0.779 Size / Complexity category Basic / “C” (trellis pattern) Number of major spawning areas (MaSAs) 1 Number of minor spawning areas (MiSAs) 0 a. All stream segments ≥ 3.8m bankfull were included. b. Temperature limited areas were assessed by subtracting area where mean weekly modeled water temperature was > 22oC. Current Abundance and Productivity Current total abundance (number of adult spawners in natural production areas) is unknown for this population. The Lolo Creek population includes spawning and rearing habitats at two