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(Centrocercus urophasianus)
Identification:
* Length: Up to 30 inches
* Large, rounded-winged, ground-dwelling, chicken-like bird
* Long, pointed tail
* Legs are feathered to base of toes
Adult male:
* Yellow comb over eye
* Blackish-brown throat and v-shaped mark on neck separated by white
* White breast
* Grayish nape, back and upper wings are white
* Black belly
* Two olive-green air sacs inflated when displaying
Adult female:
* Buffy throat with black markings
* Lower throat and breast blackish-brown
* Gray-brown plumage mottled with white and darker brown
* Dark belly
The Greater Sage Grouse:
The sage-grouse (Centrocercus urophasianus), which was first described for
science by Lewis and Clark during their 1804 expedition, is an inhabitant of the
open sagebrush plains. It is a large, ground-dwelling, chicken-like bird, up to
30 inches in length and two feet tall, weighing from two to seven pounds. It has
a long, pointed tail with legs feathered to the base of the toes. Their mottled
brown, black and white coloring serves as a camouflage from predators. The males
are larger and more colorful than females, and they have a black throat and bib,
white feathers
along the sides of the neck, and a large white ruff on the breast. Males also
exhibit two large, frontally directed air sacs of olive-green skin and yellow
combs. Both are inflated during breeding display. The sage-grouse is found from
4,000 to over 9,000 feet in elevation. It is omnivore, eating soft plants,
primarily sagebrush, and insects. One of the most interesting aspects about the
sagegrouse is its nearly complete reliance on sagebrush. Throughout much of the
year, adult sage-grouse rely on sagebrush to provide roosting cover and food.
The type and condition of
shrub-steppe plant communities strongly affect habitat use by sage grouse
populations, but these populations also exhibit strong site fidelity (loyalty to
a particular area). These birds cannot survive in areas where sagebrush no
longer exists. Sage-grouse may disperse up to 100 miles between seasonal use
areas; however, average individual movements are generally less than 21 mile
Mating Rituals:
During the spring breeding season, male sage-grouse gather together and perform
courtship displays on display areas called leks (also known as “drumming
grounds”), which are relatively open sites and often surrounded by denser
shrub-steppe cover. Males defend individual territories within leks, strutting
with tails fanned and emitting plopping sounds from the air sacs on their chests
to attract females. The mating season generally begins at the same time each
spring, but ultimately depends on weather and vegetative conditions. Some leks
are used for many years.
Females lay a clutch of 7-8 eggs from mid-March to mid-June. Sage-grouse hens
raise one brood in a season. The average life span of sage-grouse is 1 to 1-1/2
years. However, they have been found to survive up to 10 years in the wild. In
the evening until early morning, they roost on the ground. Approximately half of
sage-grouse mortality is caused by predators, including raptors, badgers, ravens
and ground squirrels (eat the eggs).
Common names for sage-grouse include: sage hen, sage fowl, sage cock, sage
chicken, heath cock and heath hen. Adult sage-grouse have dark-green toes. In
early fall, comb-like fringe appears alongside each of the three toes which then
act as snowshoes for walking on deep snow and are shed in the spring.Their
Habitat:
In the summer sage-grouse depend on sagebrush for shelter from predators, while
the grass and plants under the sagebrush provide materials for nesting and
high-protein insects for food, a critical diet for chicks in their first month
of life. In winter, over 99 percent of their diet is sagebrush leaves and buds.
Sagebrush is a woody shrub with silvery leaves that stay green all year.
Sagebrush is easily identifiable by its sharp odor, described by pioneers on the
Oregon Trail as a mixture of turpentine and camphor. Although sagebrush may seem
hardy, a sagebrush community may take years to recover from fire and some range
management practices. In some areas of the Columbian Basin where a large fire
burned 40 years ago, sagebrush has still not returned. A number of wildlife
species depend on healthy sagebrush habitat, including larks, burrowing owls,
long-billed curlews, sage sparrows, sage thrashers, loggerhead shrikes and pygmy
rabbits.
Where They Can Be Found:
The historic range of the sage-grouse included Washington, Oregon, eastern
California, Nevada, Idaho, Montana, Wyoming, western Colorado, Utah, South
Dakota, North Dakota, Kansas, Oklahoma, Nebraska, New Mexico, Arizona, and the
Canadian provinces of British Columbia, Alberta, and Saskatchewan. Sage grouse
are no longer found in Nebraska, Kansas, Oklahoma, New Mexico, Arizona, and
British Columbia. The distribution of greater sage-grouse has contracted, most
notably along the northern and northwestern periphery and in the center of the
historic range.
Rangewide estimates of sage-grouse abundance prior to European settlement in
western North America vary, but consensus estimate is that there may have been
about 1.1 million birds in 1800. The 1998 rangewide spring population numbered
about 157,000 sage-grouse. More recent estimates put the number of sage-grouse
rangewide at roughly between 100,000 and 500,000 birds.
A recent sagebrush die-off in Utah has affected approximately one million acres
of
sagebrush habitat - 600,000 acres of those are directly associated with
wildlife. It is believed that this is the only major die-off of sagebrush since
white settlers arrived in the area in the mid-1800s. At this time, the elevation
of the large die-off of sagebrush seems to be below 7,000 feet and involves
mainly Bureau of Land Management land. The die-off is thought to be a result of
the continuing stress on the plants due to the 5-year drought ongoing in Utah.
In addition, most of the sagebrush is made up of older plants, with little new
growth being found. If this drought continues, it is believed that next year
sagebrush located at higher elevations (7,000 feet and above) will suffer
similar loss. In Utah, higher elevations of sagebrush are found on USDA-Forest
Service lands.
-Information courtesy of the United States Fish and Wildlife Services
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