Environmental Assessment

AFFECTED ENVIRONMENT & ENVIRONMENTAL CONSEQUENCES CHAPTER 3
Table 3-54 Acreage of Historic Sage-Grouse Habitat by Sub-Area and Plant Association
Sub-Area Ponderosa Pine –
Sagebrush (CPS1-11)
3-168
Plant Association
Xeric Shrub (SD)
Pine Mountain 2,237 9,119 11,356
South of Pine Mountain 3,505 5,132 8,637
West of Pine Mountain 5,971 3,577 9,548
Totals 11,713 17,828 29,541
The methodology used to map historic habitat types was agreed upon by biologists for the Forest Service,
Bureau of Land Management, Oregon Department of Fish and Wildlife, and US Fish and Wildlife
Service. Occupied habitats are only partially known, and the present sites are from radio telemetry data
and observations of field biologists (Wildlife BE page 4).
A map delineating historic grouse habitats is located in the analysis file at the Bend-Fort Rock Ranger
District.
Alternative 1: In the short-term Alternative 1 would retain current quantities, quality, and distribution of
habitat for the greater sage-grouse. In the long-term (greater than 10 years) continuing tree encroachment
in existing shrub and shrub-grass habitats would result in declines in the quality, distribution and quantity
of available habitat due to the loss of shrubs and grasses that provide cover and forage (Wildlife BE page
4). The number and distribution of suitable perches for predator species would slowly increase,
potentially increasing the potential and risk of increased predation on both adults and chicks. In forested
habitats, continued expansion of overstory tree canopies would also result in reductions in the quality,
quantity, and distribution of understory vegetation used by sage-grouse for foraging and brood rearing.
Alternative 2: Alternative 2 would maintain or improve approximately 24 percent (2,782 acres) of the
historic habitat (11,356 acres) in the Pine Mountain sub-area, primarily brood rearing in mixed
forest/shrub areas, through thinning, fuel reduction, or a combination of both. No habitat enhancement
would be implemented in nesting habitat. Habitat improvements resulting from such treatments would be
relatively limited in duration; lasting only until stand densities and/or tree canopy expansion resulted in
the reduction or loss of understory vegetation, perhaps two to three decades at the most (Wildlife BE page
5).
It would also maintain or improve approximately 51 percent (4,870 acres) of the historic habitat (9,548
acres) in the sub-area west of Pine Mountain, primarily brood rearing in mixed forest/shrub areas, through
thinning, fuel reduction, or a combination of both. Habitat improvements resulting from such treatments
would be relatively limited in duration; lasting only until stand densities and/or tree canopy expansion
resulted in the reduction or loss of understory vegetation, perhaps two to three decades at the most
(Wildlife BE page 5).
Across the planning area, this alternative would treat approximately 71 percent of the historic habitat in
the ponderosa pine-sagebrush plant association group (8,208 acres total) and approximately 14 percent of
the xeric shrub plant association (12,696 acres total). No treatments would be implemented in historic
habitat in the sub-area south of Pine Mountain.
Table 3-55 summarizes the acres of historic sage-grouse habitat in the Pine Mountain sub-area affected by
proposed vegetation and fuel reduction treatments proposed under Alternative 2. None of the treatments
proposed under this alternative are affecting known occupied habitats but, in some instances, are adjacent
to known use sites.
Total