2018-03-09_PERMIT FILE - M2017049 (28)

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AO BIO-Logic Inc Natural Resource Consultants area. In the field,we used a GPS device to navigate to each sample point,and used temporary flagging to mark a 0.1-acre square sample plot with the original point at an arbitrary corner. Within the sample plot, we measured and recorded the following: 1. Each standing tree at least 1 inch diameter at breast height(dbh): species, alive or dead, dbh (using a dbh measuring tape that converts circumference to diameter). 2. Percent cover of the following vegetation layers: herbaceous, shrub, sapling tree,pole tree, mature tree, and dead and down woody debris. In each plot a single cover measurement was made by ocular estimation,with cover assigned to cover classes of 0-5, 5-10, 10-20, 20-40, 40- 60, 60-80, or 80-100%. Four photos were taken at each sample plot from the center, in each cardinal direction. Additional comments and incidental observations were recorded of any special habitat features. Data were entered into spreadsheets and summarized for analysis and comparison with FWS recommendations. RESULTS Habitat Components Present Mixed conifer forest and ponderosa pine/oak forest provide potential MSO habitat in the study area (Figure 3), and represent the MSO foraging habitat on the Ranch(Figure 4). These forest types were mapped on 283 acres(about 53% of the study area)and occur mainly on moderate to steep north, northwest, and northeast-facing aspects and 10-60% slopes. Mixed conifer forest is about 10 times as abundant as pine/oak forest. Other vegetation communities in the study area(pinyon juniper woodland and mountain shrubland)could also be used by MSO for foraging, especially in winter when MSO along Colorado's Front Range typically move to lower elevations and sometimes roost and forage in more varied vegetation types than are used for summer breeding(Johnson 1997). Rock outcrops composed of decomposing granite are present in several locations in the study area(Figure 3). They lack vertical faces, alcoves, or potholes. The rock outcrops on the Ranch do not provide suitable nesting sites for MSO, in the sense of narrow vertical-walled canyons typically used by MSO for nesting in Colorado. Forest Structure The mixed conifer and pine/oak forests in the study area are relatively young,based on tree size. Table 1 summarizes tree diameter by species. Douglas fir made up 94%of 462 trees measured,ponderosa pine 3%,and white fir 1%. Mean basal area of all tree species combined was 112 ft2/acre(Table 2),with a range among plots of 20-167.