The greater sage-grouse (Centrocercus
urophasianus) was first described by
Lewis and Clark in 1805. Its original
territory spanned over a dozen states
throughout the western region of the
United States. Currently, greater sage-grouse
occur in Washington, Oregon,
Idaho, Montana, North Dakota, South
Dakota, Wyoming, Colorado, Utah,
Nevada, and California. Greater sage-grouse
may also be found in parts of the
Canadian Provinces of Alberta and
Saskatchewan.
The greater sage-grouse’s niche is
sagebrush vegetation, at elevations
between 4,000 and 9,000 feet above sea
level. Research suggests that sagebrush
once covered about 156 million acres in
the United States. However, almost
none of the original area has been left
untouched, and about half of the current
sagebrush areas are seriously degraded.
A recent die-off in Utah, apparently
related to sustained drought conditions,
affected nearly one million acres of
sagebrush habitat. Most of this
sagebrush consisted of older plants, and
little new growth is occurring in this
region. Destruction of sagebrush habitat
is typically associated with overgrazing,
agricultural conversion, invasive species,
development, herbicides, and wildfires.
It can take up to 80 years for sagebrush
to return to a sustainable condition.
Degradation of habitat extent and quality
likely has been a main contributor to
greater sage-grouse population declines.
Range-wide estimates were thought to
be around 1.1 million birds in 1800. A
1998 range-wide spring census recorded
157,000 birds; more recent range-wide
estimates vary from 100,000 to 500,000.
Greater sage-grouse populations
declined an average of 3.5 percent per
year from 1965 to 1985. Although the
greater sage-grouse population is still
declining, the rate of decline since 1985
has slowed to 0.37 percent annually
across its range.
Biology
The greater sage-grouse is a large round-winged
ground-dwelling bird. It can
measure to 30 inches in length and two
feet in height, weighing from two to
seven pounds. Greater sage-grouse have
long, pointed tails with legs feathered to
the base of the toes. Females are a
mottled brown, black, and white color.
Males are larger than the females, and
have a characteristic white “ruff” around
their neck with bright yellow air sacs on
their breast, which they inflate during
mating displays.
During the spring mating season, large
numbers of males congregate on sites
called “leks” (or “drumming grounds”)
to perform a communal courtship
strutting display. Leks are relatively
small, open sites often surrounded by
denser sagebrush. Males strut with their
tails fanned and emit loud “plops”
produced by large air sacs on their
chests.
After mating, females build nests, lay
eggs, and raise chicks, without the
male’s assistance. On average, a female
greater sage-grouse will lay 2 eggs every
3 days for about 9 days. Generally,
clutch size is 6 to 8 eggs and the
incubation period is 25 to 27 days.
The greater sage-grouse depends almost
entirely on sagebrush for food and cover.
It constructs a nest from grasses and
other plants that are typical of sagebrush
habitat. During the summer, the greater
sage-grouse diet consists of insects that
are found in the sagebrush ecosystem.
During winter, 99 percent of their diet is
sagebrush leaves and buds. The average
lifespan is 1 to 1-1/2 years but sage-grouse
have been known to live up to 10
years.
Greater Sage-Grouse
(Centrocercus urophasianus)
U.S. Department of Defense and U.S. Fish & Wildlife Service
Male greater sage-grouse.
Photo: Gary Kramer, USFWS
Range of greater sage-grouse (NatureServe,
2003) and Department of Defense lands.
Map: Chris Eberly, DoD PIF
Drawing: USFWS
FWS Status Review
Between 1999 and 2001, the U.S Fish
and Wildlife Service (FWS) received
three petitions to list the greater sage-grouse
range-wide as endangered or
threatened and began a formal status
review in April 2004. The review was
completed late in 2004. The FWS
determined that the species does not
warrant protection under the Endangered
Species Act at this time. However, the
status review clearly illustrated the need
for continued efforts to conserve sage-grouse
and sagebrush habitat on a long-term
basis. The status review found 92
percent of the known active leks occur in
10 core populations across 8 western
states and that 5 of these populations are
large and expansive. The greater sage-grouse
is currently identified as a Bird of
Conservation Concern by FWS and is
listed as endangered in Canada.
The Military’s Role
At least 35 different Army installations,
as well as numerous Army National
Guard and Army Reserve properties, fall
within the current range of the greater
sage-grouse; the Air Force, Navy, and
Marine Corps have a combined 12
installations in this species’ range. There
are eight known military installations
with confirmed populations of greater
sage-grouse. Six of these are Army
sites—Dugway Proving Ground (UT),
Sheridan Training Area (WY), Camp
Guernsey (WY), Hawthorne Army Depot
(NV), Tooele Army Depot (UT), and
Yakima Training Center (WA). The other
two are Air Force Bases (AFB)—Nellis
AFB (NV) and Mountain Home AFB
(ID).
Through the use of Integrated Natural
Resource Management Plans (INRMPs),
the military has implemented
conservation actions for this species.
These plans are unique to each
installation and outline the steps that need
to be taken for land, resource, and species
conservation. Installations that have
confirmed the presence of sage-grouse
include the species in the INRMP. Other
installations with appropriate sagebrush
habitat within the range of sage-grouse
conduct surveys and manage potential
habitat.
Yakima Training Center developed and
implemented a greater sage-grouse
management plan as part of its INRMP.
This plan includes translocating birds to
diversify the gene pool, maintaining high
quality habitat, and reducing threats from
fire and predation. Efforts taken by the
Yakima Training Center have
significantly improved the numbers and
genetic diversity of the Columbia Basin
distinct population segment of greater
sage-grouse, a candidate species that is
warranted for listing but precluded by
higher listing priorities. At Hawthorne
Army Depot, nesting and lek sites are
fenced for protection, cattle have been
excluded, and sage-grouse hunting
discontinued.
Mountain Home AFB has been
implementing conservation actions for
the greater sage-grouse since 1998,
including research, habitat mapping,
surveys, and avoidance protocol. To
support these efforts, the installation has
trained ground emitter crews to identify
the species, sagebrush habitat, and
noxious weeds. Emitter crews must
report any sightings of sage-grouse or
noxious weeds to the natural resources
office. The base also restricts ground use
of emitter sites during the breeding
season, strives to prevent man-made
fires, and coordinates with the local Sage-
Grouse Working Group, one of many
such groups that exist to coordinate and
evaluate conservation efforts. Between
1998 and 2004, the installation invested
over $3 million in greater sage-grouse
conservation efforts.
Nellis AFB discovered a small group of
greater sage-grouse on one of its training
ranges. Another restricted-access range
has suitable habitat, but cannot be
surveyed on foot. Helicopter surveys are
being considered to determine the extent
of suitable habitat and confirm the
presence of greater sage-grouse, if
possible. The installation is considering a
number of projects to include in their
INRMP update, such as the potential for
additional ground and aerial surveys,
initiation of a monitoring program,
assessment of potential sage-grouse and
habitat management needs, and a study of
the potential impact of the wild horse
population on sage-grouse habitat.
Naval Air Station Fallon (NV) has not
confirmed the presence of greater sage-grouse.
However, populations occur in
nearby mountain ranges, and suitable
habitat is found on the Naval Air Station.
The installation conducts surveys to
determine species presence and has
implemented noxious weed and soil
erosion control programs. Much of the
historic sagebrush habitat around Naval
Weapons Systems Training Facility
Boardman (OR) has been converted to
agriculture. Boardman’s sagebrush is
largely isolated from other large blocks
of sagebrush. Though greater sage-grouse
are not currently known to occur on the
installation, invasive weed and erosion
control efforts are benefiting native plant
communities, including sagebrush, and
may ultimately result in suitable habitat
for population translocation.
Department of Defense (DoD)
installations are committed to
stewardship that will benefit current and
future populations of greater sage-grouse.
T h r o u g h p a r t n e r s h ips an d
implementation of installation INRMPs,
DoD is enacting conservation measures
on existing sagebrush habitat and
appropriate restoration actions for
degraded habitat to stabilize or increase
populations of this enigmatic species of
the sagebrush steppes.
Program Contacts:
Conservation Team Leader, Office of
the Deputy Under Secretary of Defense
(Installations and Environment)
703-604-0524
http://www.denix.osd.mil/conservation
Program Manager, Department of
Defense Partners in Flight Program
540-349-9662
http://www.dodpif.org
Chief, Division of Partnerships and
Outreach, Endangered Species
Program, U.S. Fish and Wildlife Service
703-358-2390
http://ww.fws.gov/endangered
August 2006
Sagebrush habitat, Yakima Training Center.
Photo: Yakima Training Center
