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Federal Register / Vol. 69, No. 168/Tuesday, August 31, 2004/Rules and Regulations 53209 Gutierrez and Rinkevich 1991, Service 1995). Although the structural characteristics of owl habitat vary depending on uses of the habitat (e.g., nesting, roosting, foraging) and variations in the plant communities over the range of the subspecies, some general attributes are common to the subspecies' life - history requirements throughout its range. Protected areas include all known owl sites (PACs), all areas in mixed- conifer and pine -oak types with greater than 40 percent slopes where timber harvest has not occurred in the past 20 years and administratively reserved lands, such as Wilderness Areas or Research Natural Areas. Restricted habitat includes mixed- conifer forest, pine -oak forest, and riparian areas adjacent to or outside of protected areas. These habitat areas are used by resident (i.e., territorial) owls for foraging, since the 600 acres recommended for PACs include on average 75 percent of nighttime foraging locations of radioed birds. The restricted areas also provide habitat for non - territorial birds (often referred to as "floaters "), to support dispersing juveniles, and to provide replacement nest/roost habitat on the landscape through time. For example, restricted habitat can succeed to protected habitat by replacing protected habitat that has been lost by fire or decay, thereby providing additional protected habitat that will assist in the conservation of the owl. These areas are essential to the conservation of the species because they encompass habitat that is required by the owl to complete its life cycle and are needed for recovery. Other forest and woodland types (ponderosa pine, spruce -fir, pinyon - juniper, and aspen) are not expected to provide nesting or roosting habitat for the owl (except when associated with rock canyons). Thus, activities in areas defined as other forest and woodland types would not require section 7 consultation unless specifically delineated within PACs. The minimum mapping unit for this designation does not exclude all developed areas, such as buildings, roads, bridges, parking lots, railroad tracks, other paved areas, the lands that support these features, and other lands unlikely to contain the primary constituent elements. Federal actions limited to these areas would not trigger a section 7 consultation, unless they affect protected or restricted habitat and one or more of the primary constituent elements in adjacent critical habitat. Canyon habitats used for nesting and roosting are typically characterized by cooler conditions found in steep, narrow canyons, often containing crevices, ledges, and /or caves. These canyons frequently contain small clumps or stringers of ponderosa pine, Douglas -fir, white fir, and/or pinyon - juniper. Deciduous riparian and upland tree species may also be present. Adjacent uplands are usually vegetated by a variety of plant associations including pinyon - juniper woodland, desert scrub vegetation, ponderosa pine= Gamble oak, ponderosa pine, or mixed - conifer. Owl habitat may also exhibit a combination of attributes between the forested and canyon types. Section 7 consultation may be required in adjacent vegetated uplands when there are one or more primary constituent elements present within these areas that meet the definition of protected or restricted habitat. The primary constituent elements for these adjacent vegetated uplands are identified below under forest habitats. We anticipate that Federal agencies will use their expertise and discretion in determining whether adjacent vegetated lands (i.e., rims or mesa tops) contain one or more of the primary constituent elements. Space for Individual and Population Growth and Normal Behavior Owls have been recorded in the Arizona, Colorado, New Mexico, and Utah, particularly mature mixed - conifer forests, pine -oak forests, and canyon habitat (Skaggs and Raitt 1988; Ganey et al. 1988; Ganey and Balda 1989a; Gutierrez and Rinkevich 1991; Willey 1993; Fletcher and Hollis 1994; Seamans and Gutierrez 1995; Gutierrez et al. 1995; Ward et al. 1995; Geo- Marine 2004), primarily above 6,000 ft and below 9,350 ft elevation ( Zwank et al. 1994; Seamans and Gutierrez 1995; Tarango et al. 1997; Young et al. 1998; Geo- Marine, Inc. 2003, 2004). These vegetative communities appear to be especially important (Ganey and Balda 1989; 1994; Fletcher 1990; Zwank et al. 1994; Seamans and Gutierrez 1995; Grubb et al. 1997; Tarango et al. 1997; Young et al. 1998; Geo- Marine, Inc. 2003, 2004). Slope angles range from 0 to 67 degrees ( Tarango et al. 1997, Geo- Marine, Inc. 2003). Mature mixed - conifer forests, pine -oak forests, and canyon habitat are characterized by the presence of a variety of large trees, down and dead woody material, and a diversity of plant species and vegetation layers. These communities include, but are not limited to, Douglas -fir, white fir, limber pine, or blue spruce forest. Owls are also found in pine -oak, and in riparian forests dominated by various species of broadleaved deciduous trees and shrubs (Service 1995). Steep narrow canyons sometimes associated with riparian forests or scattered trees are utilized by owls in southern Utah, northern Arizona, and northern New Mexico (Service 1995, Gutierrez and Rinkevich 1991). Canyon habitat is also found in southeastern New Mexico and southwest Texas. Owls have been documented using riparian drainages for nesting, roosting, and dispersal (Gutierrez and Rinkevich 1991; Willey 1998). Drainages throughout these areas concentrate available moisture, influencing the diversity and structure of the vegetation. Even small sources of water such as tiny pools or puddles create humid conditions that may influence the use of an area by owls (Geiger 1965 in Gutierrez and Rinkevich 1991). In canyon habitats, riparian sites are characterized by various species of broadleaved deciduous trees and shrubs that typically grow bigger and occur in higher densities within the drainages. Most owls are considered non- migratory throughout their range. Research and monitoring ( Zwank et al. 1994) have documented year -round occupancy of known home ranges (the area used by owls throughout the year). However, researchers have documented seasonal movements by owls. Some individuals occupied the same area year - round, some remained in the same general area but exhibited shifts in habitat use patterns, and some migrate considerable distances 12 -31 miles (mi) (20-50 kilometers [km]) during the winter, generally migrating to more open habitat at lower elevations (Ganey and Balda 1989b; Willey 1993; Ganey et al. 1998). Bond et al. (2002) reported high site fidelity within eleven spotted owl territories in California, Arizona, and New Mexico following wildfires. Therefore, it is important that.owls have home ranges of adequate size to provide for their life history requirements throughout the entire year. Owl dispersal patterns have been documented. The onset of juvenile dispersal is sudden and in various directions (Arsenault et al. 1997; Willey and C. van Riper 2000). Juvenile dispersal takes place in September and October, with 85 percent leaving in September (Gutierrez et al. 1995; Arsenault et al. 1997; Willey and C. van Riper 2000). Ganey et al. (1998) found dispersing juveniles in a variety of habitats ranging from high - elevation forests to pinyon - juniper woodlands and riparian areas surrounded by desert grasslands. In Arizona, New Mexico, and Utah, owls were observed moving across open low desert landscapes between islands of suitable breeding habitat (Ganey et al. 1998; Arsenault et al. 1997; Willey 1998). Trees of appropriate size and spacing appear to be necessary for successful dispersal,