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SAGE GROUSE
Centrocercus urophasianus
Family Phasianidae - Partridges,Grouse and Allies
Order Galliformes - Pheasants, Grouse, Ptarmigan and Allies
Risk Status
Official status
The Sage Grouse is currently on British Columbia's Red
List (CDC = G4
SX) and is classified as Extirpated
provincially. COSEWIC
also lists Sage Grouse as Extirpated.
Image Credits: photo by Andrew Niemann
in Birds of British Columbia, Campbell et al., 1990.
Historical facts
Apparently once a rare resident, the Sage Grouse is now extirpated
despite attempts at reintroduction.
In British Columbia, the Sage Grouse was always a rare bird in
the extreme south of the Okanagan and Similkameen valleys before
its local disappearance in the first quarter of the twentieth century.
There were no Sage Grouse sightings in British Columbia in the
years between 1918 and 1958. On 21 August 1958 the British Columbia
Fish and Wildlife Branch released 57, young Sage Grouse, north of
Richter Lake, Richter Pass. The programme was a complete failure.
Since then, there have been several reports of Sage Grouse around
Osoyoos but it is likely that these are stragglers from south of
the International border, where Sage Grouse still exist today.
Distinguishing features
Common names for Sage Grouse include: sage hen, sage fowl, spine-tail
grouse, fool hen, cock-of-the-plains, spiney-tailed pheasant, sage
cock, and sage chicken. Male Sage Grouse are called: old toms, master-of-the-plains,
turkey buzzards, turkey goblers, pheasant-tailed grouse, prairie
turkeys, bustards, sage fowls, heath cocks. Female Sage Grouse are
referred to as: brush hens, battle hens, and heath hens.
Both sexes have narrow, pointed tails, feathering to the base
of the toes, and a diverse pattern of grayish brown, buff, and black
on the upper body. The flanks
are pale grey and white, and there is a large dark patch extending
across the lower breast and abdomen. Adult Sage Grouse have dark-green
toes. In early fall, a comb-like fringe appears alongside each of
the three toes which then act as snowshoes for walking on deep snow;
these fringes are shed in the spring.
The males are larger and more colourful than females (2 to 3 kg),
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-superciliary
combs; both are enlarged during breeding display. The smaller females
(1 to 2 kg) lack black and white feathers on the neck and instead
have grayish-white upper throats.
The feathers that cover the longer tail feathers (coverts) in
females have white tips. Larger size, dark belly, and absence of
white outer-tail feathers distinguish Sage Grouse from Sharp-tailed
Grouse, a possible inhabitant of Sage Grouse range.
Distribution
Map
Red dots indicate specimen records or confirmed breeding sites.
British Columbia
The Sage Grouse is formerly found in the south Okanagan and Similkameen
Valleys.
The region probably offered only marginal habitat and, being at
the northern limit of its range, Sage Grouse probably were not very
secure in British Columbia. It is even possible that the great period
of overgrazing of the grasslands between 1860 and 1900 resulted
in an increase in sagebrush acreage, considerably improving Sage
Grouse habitat. The historical range of the Sage Grouse in the Okanagan
valley now overlaps areas heavily populated by humans.
North America
The Sage Grouse breeds from central Washington, southern Idaho,
Montana and western North Dakota; south to eastern California, Nevada,
southern Utah and western Colorado. Formerly in New Mexico. Also
noted in South Dakota and Wyoming.
Subspecies Centrocercus urophasianus urophasianus is a
permanent resident in southeastern Alberta and southwestern Saskatchewan.
The western subspecies, Centrocerus urophasianus phaios,
now extirpated in southern British Columbia, ranges from east-central
Washington to southeast Oregon. It also is extirpated in Nebraska,
New Mexico, and Oklahoma.
Habitat
Sage Grouse inhabit higher sage-brush plains, and in BC were restricted
to the extreme south Okanagan, where the habitat consisted of moderately
open sagebrush with a canopy coverage of 20-50%. Low rolling hills
and adjacent valleys provide the best topography for sage grouse.
They prefer slopes that are facing south year round. Wildlife managers
suggest preserving habitat at least 2.4 km around Sage Grouse leks
(courting/display grounds).
They nest under sage with an average height of 40.4 cm and a canopy
cover of 20-40%. In winter, Sage Grouse inhabit dense sagebrush
with a canopy coverage greater than 20%, in areas where the brush
stands an average 25 cm above snow. Wintering sites without protruding
sagebrush are not used. Winter habitat is typically the limiting
factor for survival of this species. Summer and winter ranges are
often widely separated, therefore corridors of sagebrush must be
preserved to allow these birds to travel with the changing seasons.
Why is it endangered?
Sources of sage grouse mortality include predation,
hunting, disease and parasitism,
accidents, and environmental hazards such as pesticides and highway
traffic. Predation is a limiting factor throughout the year but
increases during the nesting/egg-laying period and the brood-rearing
period.
The Sage Grouse has been heavily impacted by reduction of range
and uncontrolled hunting. The restricted range resulting from livestock
grazing and agriculture has meant that there probably is not enough
habitat left in British Columbia for grouse reintroduction.
The decline of the grouse was attributed to the loss of steppe
shrub habitat. Agriculture, excessive livestock grazing, and sagebrush
control using herbicides and fire are primarily responsible for
loss of shrub steppe. These continue to threaten Sage Grouse habitat
in addition to irrigation projects; commercial, industrial, and
power development; and military training activities.
It is known that reduction of sagebrush cover reduces male attendance
and nest success, and Sage Grouse with young avoid meadows which
lack adequate cover.
Biology
Breeding
Female Sage Grouse are sexually mature their first fall and nest
the following spring. Males are sexually mature their first spring
after hatching. Juvenile males engage in display and breeding but
devote less time and energy to courtship activities than adults.
The mating season begins around the same time each year but ultimately
depends on weather and plant growth. Mating begins after males and
females congregate on a lek. Hens form a cluster near a centrally-located,
dominant male, and the few dominant males participate in most of
the mating.
Leks range in size from 0.04 to 40 ha, and are often near nesting
habitat and between areas used in winter and summer. Most leks contain
a central area that is barren but surrounded by shrubs. Visibility
is important; it is necessary for females to observe displaying
males and for all Sage Grouse to spot potential predators. Almost
any cleared area can be used as a lek, including man-made clearings
such as gravel pits, burned areas, plowed fields, air strips, abandoned
homesteads, and roads. Water is not necessary on a lek, although
leks are often located near water. In areas containing both Sage
Grouse and livestock, Sage Grouse may form leks near water because
the frequent visits by livestock tend to flatten vegetation.
After mating, sage grouse hens leave the lek to nest approximately
2 to 6 km away. They devote most of their time to building nests,
laying eggs, and raising chicks; males do not assist in these activities.
Females build nests approximately 10 days after mating in shallow
depressions on the ground, sparsely lined with grass and sheltered
by sagebrush or clumps of grass. Females lay up to 7-8 eggs and
incubate them for 25-27 days (mid-March to mid-June). After hatching,
chicks remain in the nest until dry, and then they leave the nest
to follow the hen. Sage Grouse hens raise one brood per season,
and spend considerable time keeping chicks warm and guarding them
for the first 4 to 5 weeks. Sage Grouse chicks feed themselves.
By the end of the second week, chicks can fly several metres and
several hundred metres by the eighth week. Chicks remain with hens
until late summer or early fall, and then they join other sage grouse
in winter flocks.
Behaviour
The Sage Grouse is the largest North American grouse and has spectacular
courtship rituals. Male and female Sage Grouse gather at a lek each
spring, and males establish small territories on the lek. Males
vocalize to attract females to the lek and display to induce copulation
and will use the same strutting grounds for generations. Female
sage grouse show submissive behaviour (e.g. slimmed plumage, silent
movements) to avoid the hostility characteristic of male-male encounters.
When males encounter each other, they lower their tails and release
air from their esophagus. Males step around each other, and use
their wings to strike the opponent in the body or head. Males also
peck each other or bite each others beaks. Aggressive female-female
encounters also occur, especially during breeding and nesting.
During most of the year, Sage Grouse segregate into flocks according
to sex and confine most of their activities to within 3 km of a
lek. In late summer and early fall, Sage Grouse congregate in heterogenous
flocks in preparation for movement to wintering grounds. Similar
congregations occur in late winter or early spring before movement
to breeding areas. Not all Sage Grouse populations migrate
and congregations may remain near the lek year-round.
Sage Grouse spring directly into the air to fly. When flying,
they flap their wings 5 to 8 times then glide for 23 to 32 m. This
pattern is repeated until they are in flight. When landing, Sage
Grouse often touch the tips of their wing and tail feathers to the
ground in order to balance themselves. An average flight height
of 14 m has been recorded for females and 23 m for males. The average
time spent in the air was 13 seconds for hens (females) and 25 seconds
for cocks (males) with average distances flown being 221 m for hens
and 575 m for cocks.
The average life span of Sage Grouse in both hunted and protected
populations is 1 to 1.5 years. Sage Grouse 3 to 4 years old are
considered old, however, Sage Grouse up to 10 years have been recorded
in wild populations.
The Sage Grouse usually roost on the ground from evening until
early morning, feed and rest during the afternoon, and return to
their roosting site at night.
Diet or Growing requirements
Historically, the large range and uniformity of shrub-steppe habitat
contributed to specialized feeding in Sage Grouse. Sagebrush is
the most important component of the Sage Grouse diet but varies
in use depending on the season. Forbs
and grasses including leaves, blossom pods, and buds of other plains
plants are also a significant food source for Sage Grouse. Sage
Grouse also consume insects when available; however, insects compose
only a small proportion of the diet of adult grouse.
In the first week of life, chicks rely heavily on insects such
as grasshoppers and ants. In the fall, the Sage Grouse diet shifts
to a diet dominated by sagebrush due to colder temperatures, snow
accumulation and changes in vegetation. In the winter, they depend
entirely on soft evergreen leaves and shoots of sagebrush.
Predators
Predation, especially during nesting, egg laying, and brood rearing,
limits the growth of Sage Grouse populations. Approximately 50%
of sage grouse mortality
is caused by predators. Adults are more vulnerable to predators
in winter because snow makes them more visible. Predation
during winter depends on the availability of alternative prey for
predators, such as cottontail rabbits and jack rabbits. Habitat
quality, specifically the amount and type of vegetation and cover
available to hens when building nests, ultimately determines the
number of nests detected and destroyed by predators.
Ravens, coyotes, badgers, and ground squirrels are primary predators
of Sage Grouse eggs. Golden Eagles, Prairie Falcons, Short-eared
Owls, Gyrfalcons, Northern Harriers, Goshawks, Ravens, crows, Magpies,
and a variety of hawks, as well as Coyotes, Bobcats, Minks, and
Badgers also take Sage Grouse chicks and adults.
Sources for more
information
Related On-line Sites to Visit
Publications
Birds of the Okanagan Valley , Cannings, 1987, p. 150
The SOCAP Workshop Summary, The Nature Trust, 1989
Habitat Conservation Fund , August 1992
Washington Department of Fish and Wildlife. 1995. Washinton State
management plan for sage grouse. Game Div., Wash. Dep. Fish and
Wildl., Olympia. 101 pp.
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