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AO <br /> 1W BIO-Logic <br /> me <br /> Natural Resource Consultants <br /> Vegetation in the 536-acre study area varies with elevation, slope,aspect, and soil type. Mixed conifer <br /> forest and ponderosa pine/Gambel oak woodland are the vegetation types that comprise MSO habitat, and <br /> these communities are described below. The study area also contains pinyon juniper woodland, mountain <br /> shrubland, and rock outcrops. <br /> Mixed Conifer Forest <br /> Mixed conifer forest is the more common community in the study area, comprising approximately 264 <br /> acres. It is dominated by Douglas fir(Pseudotsuga menziesii),with fewer ponderosa pine(Pinus <br /> ponderosa)and white fir(Abies concolor). Ponderosa pine is codominant in some locations but a minor <br /> component overall. White fir is a minor component, found primarily on lower slopes closer to drainage <br /> bottoms. Douglas fir is present primarily in younger age classes—sapling, pole and immature size trees. <br /> Ponderosa Pine/Gambel oak <br /> Pine/oak stands occur in four locations covering a total of approximately 18 acres. Stands are small in <br /> size, scattered,and generally favor south or southeast-facing slopes. The stands generally contain a mix <br /> of immature and mature trees. Oak in the understory is generally present in patches of varying age <br /> classes and average 3-6 feet in height. Douglas fir is also present in these stands. Herbaceous vegetation <br /> is scarce, consisting of scattered patches of grasses and forbs. Woody debris is scarce. <br /> MSO HABITAT DEFINITIONS <br /> A large number of scientific studies have been published on MSO habitat characteristics and seasonal use <br /> patterns;these are extensively evaluated and summarized in the FWS rules detailing the listing(FWS <br /> 1993)and critical habitat designations(FWS 2004)for MSO. MSO inhabit a broad range of landscapes <br /> from northern Mexico to central Colorado. <br /> MSO breeding habitat includes the nest site and adjacent areas used for foraging and roosting during the <br /> breeding season, approximately April through August. On the Front Range of Colorado,MSO breeding <br /> habitat consists of rocky, sheer-walled canyons with ponderosa pine or mixed conifer forests,between <br /> about 6,500 and 8,500 feet elevation(Johnson 1997). These canyons appear to provide important thermal <br /> cover to resist high summer temperatures;rock ledges and caves for nesting and roosting; an abundance <br /> of woodrats, a primary MSO prey species; and protection from predators(Johnson 1997). Across much <br /> of its North American range MSO commonly place nests in stick platforms placed in tall trees(FWS <br /> 2012a),but in Colorado every MSO nest documented to date has been on a ledge, alcove, or cave on <br /> sheer rock walls(Johnson 1997, Leslie Ellwood,FWS,personal communication 2016). <br /> Foraging habitat requirements include forest stands with a mix of tree species including conifers and <br /> hardwoods,and vegetation structure that promotes an abundance of prey, mainly small mammals(FWS <br /> 2012a)and in Colorado particularly woodrats(Johnson 1997). The presence of surface water in streams <br /> or ponds enhances foraging habitat. In general throughout the range of MSO, older age stands of mixed <br /> ----- — --- ------ <br /> 5 <br />