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Lorencito Canvon Mirte ~ Wildlife Technics( Reyort • Cliffs are the preferred nesting substrate, however, tall man-made structures (i.e.: high rise buildings and towers) may be used (Spahr et al, 1991). Breeding begins in March when males establish territories. Three to four eggs are laid in mid- April. Incubation lasts from 33 to 34 days. The young hatch in mid-May. Young generally fledged in 6 weeks and remain dependent on the adults for several weeks (Spahr et al., 1991). Peregrines typically prey on birds such a waterfowl, shorebirds, grouse, and pigeons. Prey is taken by striking from above after a high speed dive. Foraging occurs within ten miles of the nest, however, 80 percent occurs within a one mile radius of the nest (Spahr et al., 1991). Peregrine falcons usually migrate to Mexico or Central America th the fall. However, some birds may stay on their breeding grounds year-round if food supplies aze available (Spahr et al., 1991). Peregrine falcons are not anticipated to occur within the permit area. This lack of occurrence is based on the following considerations. First, suitable nesting habitats, such as cliffs, are not present within the permit area. Second, the preferred prey species and the peregrine do not occur within the permit area. Although wintering waterfowl may occur on the Purgatorie River, they occur during the season that peregrines would not occur within the area. Lastly, no peregrine habitat was identified by the resource management agencies within or near the permit area. • Mexican Spotted Owl The Mexican spotted owl is afederally-listed threatened species. The Mexican spotted owl typically roosts in virgin mixed coniferous forests. With narrow, shady, cool canyons within sandstone slick rock. Within these areas the owls roost in the riparian vegetation such as cottonwoods and Boxelder on the canyon bottoms. They also may roost on ledges or cavities in slick rock canyon walls. (Forest Service, undated). Within these forests an understory of Gambel oak, Rocky mountain maple, and small conifers was common. These stands have downed logs, snag and mistletoe infestations typical of old stands of trees (Forest Service, no date). In addition, spotted owls appear to nest on steep mountainsides and within steep, narrow canyons and near rockfaces. However, they appear to avoid non-forested areas (Ganey and Balda, 1994). The mean home range of paired owls is approximately 2,092 ha (Ganey and Balda 1989). Nesting occurs in cavities, abandoned stick nests, debris platforms, and cliffs. Nesting begins in early March, with 2~ eggs laid in early to mid-April. The owlets hatch th early to mid-May, and leave the nest by early to mid-June. Spotted owls are nocturnal predators that prey on woodrats, white- footed mice, voles, rabbits, and pocket gophers (Spahr et al, 1991). Within Colorado, these owns most commonly utilize mixed coniferous forests that contain white fir, Douglas-fir, and Ponderosa pine in the overstory. Also within southwestern Colorado, northeastern Arizona, and Utah, Mexican spotted owls occur at elevations ranging from 4,800 to • 6,800 feet. These areas are comprised of pinyon juniper stands. Wildlife.475/December ~3, i996 24