Wildlife Specialist report

Spotted Owl and determined that road and trail associated factors that were likely to
affect spotted owls were collisions, disturbances at a specific site, physiological
responses, edge effects, and snag reduction. These same factors are expected to affect the
MSO. During a study investigating noise effects to MSOs, Delaney et al. (1999) found
that owls did not flush from roosts or nests when chainsaws were used greater than 105
meters away. Mexican Spotted Owls were determined to be capable of hearing road
construction noise from as far as 400 meters away, though responses to these noises were
not documented (Delaney and Grubb, 2004). A study investigating noise disturbance
from helicopters on the Lincoln National Forest indicated that a 105 meter buffer zone for
helicopter over flights would minimize MSO flush response and any potential effects on
nesting activity (Delaney et al. 1999). To analyze effects to this species from the
proposed action and each alternative of the Travel Management Project on the GNF
analysis will focus on two factors:
1) To analyze the potential for harvest/direct disturbance effects of motorized activities
to MSOs we will measure road miles within PACs, MSO Critical Habitat, and within the
mixed conifer vegetation type as these miles pertain to the existing condition and the
change proposed in each alternative.
2) To analyze potential disturbance/indirect effects we will use a disturbance zone of 105
meters with in PACs, Critical habitat, and Mixed Conifer vegetation types as it pertains to
the existing condition and to the change proposed in each alternative.
Northern Goshawk (Regionally Sensitive Species, Management Indicator Species
Representative of Ponderosa Pine Habitat Cover Type, and NM PIF High Priority
Species with Known Management Areas Defined on the GNF) - Northern goshawks
occupy a variety of habitats including mature coniferous and deciduous forests, typically
from approximately 4,750 to 9,120 ft in elevation (AZGF, 2003). The principal forest
types occupied by the goshawk in the Southwest are ponderosa pine, mixed-species, and
spruce-fir. Nest sites are generally in stands of larger trees with dense canopy cover, and
generally in larger tracts of forests over smaller tracts. Reynolds (1983) and Kennedy
(1988) report that goshawks apparently prefer to nest within 1/4 mile of water in forest
blocks > 80 ha in size which contain small openings. In Arizona, goshawk’s nest most
commonly in ponderosa pine forests along the Mogollon Rim (AZGF, 2003). On the
Gila National Forest, nests have also typically been located in ponderosa pine vegetation.
A Post-fledgling Family Area (PFA) is the area of concentrated use by the goshawk
family after the young leave the nest (Reynolds et al, 1992). The PFA surrounds the nest
and is approximately 600 acres. Fifty eight (58) PFAs have been identified on the GNF.
The Forest Plan Amendment standards and guidelines state: Limit human activity in
PFAs during the breeding season; limit human activities in or near nest sites and postfledgling
family areas during the breeding season; manage road densities at the lowest
level possible.
Certain kinds of human disturbances to goshawk nests have been a speculated to cause
nest abandonment (Reynolds et al. 1992). A study investigating affects of logging truck
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