Wildlife Specialist report

Bighorn Sheep (Forest Service Sensitive Species)
Table 15: Bighorn Sheep Analysis Area - Existing Condition and Proposed Change
Table by Alternative:
Total NMGF Core Bighorn
Habitat on USFS = 68,737 Acres
Motorized Routes
Existing
Effects Change in Effects
Alt B
(No
Action) Alt C Alt D Alt E Alt F Alt G
Open Existing ML 2 - ML 5 Miles 34 -3 -15 -23 -5 -13
Acres 5,734 -515 -2,282 -3,387 -956 -2,089
Administrative Route Miles 0 4 5 5 5 5
Acres 0 750 941 941 916 916
Add Unauthorized Route Miles 0 0 0 0 0 0
Motorized Trails
Acres 0 33 146 0 33 146
0 0 0 0 0 0
Total FS Routes and Trails Miles 34 35/+1 24/-10 16/-18 33/-1 26/-8
Percent in Miles of Alt. B (Existing) %Miles
3.41% -27.16% -51.34% -0.29% -21.80%
Motorized Dispersed Camping Acres 46,160 -44,615 -45,676 -46,160 -45,262 -45,700
Percent in Acres of Alt. B (Existing) %Acres
-96.65% -98.95% -100.00% -98.05% -99.00%
Motorized Areas Acres 0 NC NC NC NC NC
Motorized Big Game Retrieval Acres 46,160 -8,712 -45,676 -46,160 -23,094 -45,700
Percent in Acres of Alt. B (Existing) %Acres
-18.87% -98.95% -100.00% -50.03% -99.00%
No Action Alternative (Alt. B): ): Under this alternative there are 34 miles of
motorized routes in bighorn sheep habitat, which continues to cause habitat loss and the
potential for other types of direct effects to this species. The potential for collision loss
does exist on Forest Service motorized routes; however, lower traffic rates and travel
speeds on forest routes reduce this potential. Increases in road densities increases the
potential for take associated with poaching. The potential disturbance zone (5,734 acres)
along motorized routes in this analysis area continues to cause the potential for indirect
effects. Papouchis et al. (2001) reported that their findings were consistent with other
research that roads cause a zone of influence larger than the road itself. In high use areas
some sheep do habituate to road traffic but more typically the closer to a road the more
likely sheep will flee. Increases in the level of use on these routes through time would
increase the potential for direct and indirect effects.
Under this alternative you continue to have motorized cross country travel, dispersed
camping, and big game retrieval allowed across the Gila National Forest. These three
types of uses continue to have potential effects to bighorn sheep. Additionally, these
three types of uses perpetuate the development of additional roads and motorized trails;
potentially allowing for the development of greater road densities. So under this
alternative through time the potential for the direct loss of individuals and habitat would
increase, as would the potential for disturbance effects to the species and habitat.
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