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Fact Sheet FS-01-44
Sage Grouse Habitat Requirements
J. Kent McAdoo, Natural Resources Specialist, Northeast Area
Gary N. Back, Principal Ecologist, SRK Consulting
Introduction
Sage grouse (Centrocercus urophasianus)
are considered a sagebrush "obligate," even though
a portion of their life cycle is associated with
meadows. In other words, they require sagebrush
(Artemisia sp.) for their existence.
More
specifically, sagebrush is the major component of
sage grouse habitat, providing food, shelter, and
nesting cover.
Within the sagebrush habitat type, sage
grouse occur at low densities and are distributed
unevenly. They may be locally abundant on a
seasonal basis. Most of their preferred habitat is
found in low rolling hills and adjacent valleys.
Optional habitat is a diverse mosaic of sagebrushgrass with varying heights of sagebrush and a
diverse understory of perennial grasses and forbs
(broadleaf herbaceous plants). The proportion of
sagebrush, perennial grasses, and forbs in an area
vary with the species or subspecies of sagebrush,
the ecological potential of the site, and condition of
the habitat.
Sage grouse require the use of sagebrushgrass habitats yearlong; however, the species
composition and structural complexity of the
habitats used depend on the bird's seasonal
requirements. The spatial arrangement, size, and
vegetation conditions of each seasonal habitat
determine the landscape's suitability for sage
grouse. Large, old stands of sagebrush may lack the
grasses and forbs that grouse need for food and
cover. The use of sagebrush habitats and other
habitats by sage grouse is discussed below.
Breeding Habitats (Leks)
Sage grouse "leks" or breeding display sites
occur in open areas surrounded by sagebrush. Also
called "strutting grounds," these sites are often
located in low sagebrush areas, ridgetops, grassy
openings, and disturbed areas like burns. This
preference for using sparsely vegetated sites for
strutting has also resulted in the use of such altered
habitats as airstrips, gravel pits, cultivated fields,
and roads. Breeding habitats are very traditional,
being used year after year, and are considered to be
the center of year-round activity for resident grouse
populations. However, this is not the case for
migratory populations.
Breeding displays on the leks typically begin
in March or April. Males display on these sites in
gatherings of a few to a few hundred birds.
Breeding occurs in these areas as females are
attracted by the strutting displays. The sagebrush
habitat surrounding these leks is used extensively by
grouse for escape cover, protection from predators,
feeding, and loafing. The sagebrush in these
adjacent areas is typically 7 to 15 inches tall and has
a canopy cover of 20 to 50 percent.
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Pre-Nesting and Nesting Habitats
Areas used by pre- laying hens are critical
for chick survival. These areas must provide a
diversity of forbs so that the hens have a food
source high in calcium, phosphorus, and protein, all
critical to the hen's nutrition. Without proper and
sufficient nutrients, reductions in nesting rates,
number of eggs (clutch size), hatching success, and
chick survival may occur. A mosaic of good
condition low sagebrush (Artemisia arbuscula) and
big sagebrush (A. tridentata) typically provides the
forbs needed by the hens during this time. The low
sagebrush sites are especially important in terms of
forb production. Species such as hawksbeard
(Crepis sp.), long- leaf phlox (Phlox longiloba),
dandelion (Taraxacum officinale), clover (Trifolium
sp.), and milk-vetch (Astragalus sp.), are among
those preferred by grouse during this time.
After breeding, hens leave the leks to seek
suitable nesting habitat. Although the females often
nest fairly close to the leks, nesting habitat may be
several miles away. Location of nesting areas is a
function of the availability of quality habitat.
Suitable nesting habitat is typically Wyoming big
sagebrush (Artemisia tridentata wyomingensis),
communities with 15 to 38 percent sagebrush
canopy cover and a grass and forb understory. The
hens nest in a shallow depression on the ground,
usually under big sagebrush with grasses or other
vegetation providing concealment. Although shrub
heights at nest sites are variable, sage grouse tend to
nest under shrubs taller than the average shrub
height in a given area. Those shrubs that provide an
"umbrella effect" are preferred. Umbrella-shaped
canopies have branches near the ground, while treeshaped shrubs have large open areas between the
ground and lower branches.
The amount of grass cover required at sage
grouse nest sites is variable, ranging from 3 to 30%
cover at successful nest sites. Several studies have
shown that grass height and density is greater at
nest sites than at random sites. An Oregon study
showed less predation on nests in areas where
shrubs were 16 to 32 inches tall and residual grass
height was at least 7 inches. However, the relative
amount of grass required by sage grouse hens at
nest sites may also be a function of shrub shape.
Where the "umbrella effect" of shrubs is sufficient,
residual grass cover may not provide much
additional protection from predators. On the other
hand, nest sites with more grass cover provide a
warmer microclimate for eggs than those with less
cover.
Early Brood-Rearing Habitats
Young sage grouse (broods) have higher
survival rates when certain food and cover
requirements are met. Insects and forbs are the
most important food items during the chicks' first
month of life. Early brood-rearing areas typically
occur in upland sagebrush habitats close to nest
sites, although some broods may move to more
distant areas at this time.
Optimal early brood-rearing habitat has
sagebrush stands that are 16 to 32 inches tall, with a
canopy cover of 10 to 25%. The herbaceous
understories have approximately 15% grass cover
and 10% forb cover. Ideally, this preferred habitat
would be found on at least 40% of the area used by
sage grouse broods during June and early July.
However, composition and structure of the
vegetation on any site is a function of the specific
plant species and soil types found in the vicinity.
Hens with broods tend to select areas during this
time that have a wide diversity of plant species and
a corresponding diversity of insects.
Late Brood-Rearing Habitats
As food plants mature and dry during midJuly through August, grouse move to areas that
support succulent herbaceous vegetation, usually
native or irrigated meadows. In general, a mosaic
of sagebrush habitats containing grass and forbs,
along with interspersed wet meadow areas, form
optimum late brood-rearing habitats. Where alfalfa
fields and croplands are adjacent to sagebrush
habitats, they may be used by grouse during this
time of year.
Upland sage grouse habitat in Nevada is
drier than that in most western states; therefore the
meadow areas are even more important as late
summer brood habitat. From mid to late summer,
narrow meadows in drainages as well as irrigated
hay fields often provide the highest forb abundance
for young birds. During drought years, these
remaining green areas are even more important for
young sage grouse.
Fall Habitats
As the brood groups disperse in early fall,
sage grouse form flocks and use a variety of
habitats. During this time both frost and the drying
of vegetation results in reduc ed forb quality in
meadow habitats. As the vegetation dries in late
summer and early fall, sage grouse increase their
consumption of sagebrush leaves and buds. In
some years, grouse may use their summer range as
late as October. In other years, sage grouse begin
moving to wintering areas by the first week in
October. Good fall sage grouse habitat, like other
seasonal habitat, is comprised of a mosaic of
sagebrush communities with diverse species,
varying cover composition, and different height
classes.
Winter Habitats
Winter habitat for sage grouse varies
according to weather conditions. But regardless of
weather, the presence of sagebrush for food and
cover is the common denominator. Sage grouse
feed almost exclusively on sagebrush leaves at this
time of year. At least 10 to 12 inches of sagebrush
must be exposed above the snow to allow feeding
by sage grouse. Although big sagebrush dominates
sage grouse diets in most portions of this bird's
range, other sagebrush species are also eaten. In
northern Nevada, low sagebrush is used until it is
covered with snow, at which time the birds move to
big sagebrush areas.
Sagebrush is also important in winter for
cover.
Sage grouse will roost in open, low
sagebrush sites on clear, calm nights above 10°F.
However, on windy nights or during snowstorms
the birds seek out taller shrubs in areas with 20% or
more canopy cover. On cold nights when powdery
snow is available, sage grouse will burrow in the
snow to conserve energy. These birds will fly more
than 5 miles between winter- feeding and snow
roosting sites during very cold weather (below
10°F).
Summary
Sage grouse require sagebrush for food
and/or cover during each stage of their life cycle
and therefore are called "sagebrush obligates."
However, sage grouse use other habitats, like wet
meadow areas, and increase their dependence on
these habitats in mid to late summer during drought
years.
Although sage grouse depend on the
sagebrush habitat type for survival, they thrive best
in areas with a mosaic of sagebrush species, age
(height), and cover classes.
Selected References
Autenrieth, R.E. 1981. Sage grouse management in
Idaho. Idaho Department of Fish and Game
Wildl. Bull. 9.
Back, G.N., M.R. Barrington, and J.K. McAdoo.
1987. Sage grouse use of snow burrows in
northeastern Nevada. Wilson Bull. 99:488490.
Barnett, J.F., and J.A. Crawford. 1994. Prelaying
nutrition of sage grouse hens in Oregon. J.
Range Manage. 47:114-118.
Barrington, M.R., and G.N. Back. 1984. Sage
grouse research; population dynamics. P
43-46. In: P.C. Lent and R.E. Eckert, Jr.
(eds.). Progress report for 1983 Saval
Ranch Research and Evaluation Project.
Univ. Nevada Reno, Renewable Resource
Center, Reno, NV.
Beck, T.D.I., and C.E. Braun. 1978. Weights of
Colorado sage grouse. Condor. 80:241-243.
Connelly, J.W., R.A. Fischer, A.D., K.P. Reese, and
W.L. Wakkinen. 1993. Renesting of sage
grouse in southeastern Idaho.
Condor
95:1041-k1043.
Connelly, J.W., M.A. Schroeder, A.R. Sands, and
C.E. Braun. 2000. Guidelines to manage
sage grouse populations and their habitats.
Wildl. Soc. Bull. 28:967-985.
Gredd, M.A., J.A. Crawford, M.S. Drut, and A.K.
DeLong. 1994.
Vegetation cover and
predation of sage grouse nests in Oregon. J.
Wildl. Manage. 58:162-166.
Sveum, C.M., J.A. Crawford, and W.D. Edge. 1998.
Use and selection of brood-rearing habitat
by sage grouse in southcentral Washington.
Great Basin Nat. 58:344-351.
Hupp, J.W., and C.E. Braun. 1989. Topographic
distribution of sage grouse foraging in
winter. J. Wildl. Manage. 53:823-829.
Wallestad, R.O. 1971. Summer movements and
habitat use by sage grouse broods in central
Montana. J. Wildl. Manage. 35:129-136.
Klebenow, D.A. 1969. Sage grouse nesting and
brood habitat in Idaho. J. Wildl. Manage.
33:649-661.
Wallestad. R.O., and D. Pyrah. 1974. Movement
and nesting of sage grouse hens in central
Montana. J. Wildl. Manage. 38:630-633.
Klebenow, D.A. 1982.
Livestock grazing
interactions with sage grouse.
Proc.
Wildlife-Livestock Relationships Symp.,
Coeur d'Alene, Idaho. Univ. Idaho,
Moscow. pp. 113-123.
Welch, B.L., J.C. Pederson, and R.L. Rodriquez.
1988. Selection of sage grouse for big
sagebrush. J. Range Manage. 44:462-465.
Klebenow, D.A. 1985. Habitat management for
sage grouse in Nevada. World Pheasant
Assoc. 10:36-46.
Klebenow, D.A. (In Press). Enhancing sage grouse
habitat…a Nevada landowners guide. Nev.
Wildl. Fed. Pub.
Klebenow, D.A., and G.M. Gray. 1968. Food
habits of juvenile sage grouse. J. Range
Manage. 21:80-83.
McAdoo, J.K., and G.N. Back. 2001. Sage grouse
biology. Univ. of Nevada Coop. Extension
Fact Sheet 01-43. 5pp.
Patterson, R.L. 1952.
The Sage Grouse in
Wyoming. Sage Books, Inc., Denver, Co.
Remington, T.E., and C.E. Braun. 1985. Sage
grouse food selection in winter, North Park,
Colorado. J. Wildl. Manage. 49:1055-1061.
Schroeder, M.A., J.R. Young, and C.E. Braun.
1999.
Sage
grouse
(Centrocercus
urophasianus). In: The Birds of North
America No. 425, (A. Poole and F. Gill,
eds). The Birds of North America, Inc.,
Philadelphia, PA.
Figure 1. Sage Grouse Distribution
(Current & Potential)
Source: Nevada Division of
Wildlife 2001