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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 an attempt to reintroduce it. The Sage Grouse apparently was always a rare bird in the extreme south of the Okanagan and Similkameen valleys before its complete disappearance in the first quarter of the twentieth century. Historically known from the extreme south Okanagan and Similkameen Valleys. In the 40 years between 1918 and 1958 there are no records of Sage Grouse in the Valley. On 21 August 1958 the British Columbia Fish and Wildlife Branch released 57, mainly birds-of-the-year, north of Richter Lake, Richter Pass. The program was apparently a complete failure. There have been several reports of sightings around Osoyoos over the years but it is unlikely that a few stragglers still survive there. 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 and 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.
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British Columbia The region probably offered only marginal habitat and, being at the northern limit of its range, the Sage Grouse probably existed precariously. 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.
North America 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 has also been extirpated in Nebraska, New Mexico, and Oklahoma. Sage hens, as they are often called, have evolved with the plants after which they are named, and their occurrence is limited to the highter sage-brush plains. The Sage Grouse is restricted to open, big sagebrush habitats in the extreme south Okanagan. The strutting ground habitat is moderately open sagebrush with a canopy coverage of 20-50%. A minimum radius of 2.4 km around strutting ground is suggested for protection of habitat. They nest under sage with an average height of 40.4 cm and a canopy cover of 20-40%. Wintering habitat is vital due to potentially high natural mortality. They prefer dense sagebrush with a canopy coverage greater than 20% and stand an average 25 cm above snow. Wintering sites without protruding sagebrush are not used. Winter habitat is typically the most limited seasonal habitat within the range of sage grouse. Summer and winter ranges are often widely separated, therefore corridors of sagebrush along routes must be preserved. Low rolling hills and adjacent valleys provide the best topography for sage grouse. They prefer slopes that are facing south year round. Sources of sage grouse mortality include predation, hunting, disease and parasitism, accidents, and environmental hazards such as pesticides. 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 reintroduction. The decline of the grouse is primarily attributed to the loss of steppe shrub. 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. It has been found that reduction of sagebrush cover reduces male attendance and nest success and broods will avoid meadows surrounded by bare ground.
Breeding The mating season generally begins at the same time each year but ultimately depends on weather and vegetative conditions. Mating begins after males and females congregate on a lek. Hens form a cluster near a centrally-located, dominant male,and these few dominant males participate in most of the mating. Leks are the focal point of the breeding season and range in size from 0.04 to 40 ha. Leks are often near nesting habitat and between areas used in winter and summer. Gravel pits, burned areas, plowed fields, air strips, abandoned homesteads, roads, bare ridges, grassy swales, natural and irrigated meadows void of grass, knolls, small buttes, openings in sagebrush stands, dry-lake beds, and areas stripped of vegetation by livestock may be used as a lek. Most leks contain a central area that is barren and a surrounding area containing shrubs. Visibility is important on a lek and is necessary for females to observe displaying males and for all sage grouse to observe predators. 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 vegetation has been flattened or removed by repeated livestock use. After mating, sage grouse hens leave the lek to nest approximately 2 to 6 km from leks. They devote most of their time to builiding 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 clump of grass. Females lay one egg every 1.3 days for approximately 9 days. The clutch of 7-8 eggs is incubated for 25-27 days in mid-March to mid-June. After hatching, chicks wait until they are dry, then they leave the nest. Sage grouse hens raise one brood in a season. Hens spend considerable time keeping chicks warm and guarding them for the first 4 to 5 weeks; however, the chicks feed themselves. By the end of the second week, chicks can fly several yards and several hundred yards by the eighth week. After hatching, chicks remain with hens until late summer or early fall, then they congregate with other sage grouse in winter flocks.
Behaviour Mating, nesting, brood rearing, loafing, roosting, and foraging typically occur within 3 km of a lek. Males vocalize to attract females to the lek and display to induce copulation and will use the same strutting grounds used for generations by 20-70 males. Female sage grouse show submissive behaviour (e.g. slimmed plumage, silent movements) to avoid male hostility characateristic of male-male encounters. When males encounter each other, they lower their tails and release air from their esophagus. Males remain grounded, face and 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. 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 in the area. Sage Grouse spring directly into the air to fly. When flying, sage grouse 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 in 1 to 1.5 years; Sage Grouse 3- to 4-years old are considered old. However, Sage Grouse can survive up to 10 years in the wild. 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 In the first week of life, broods 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 Raptors and crows are primary predators of Sage Grouse; ravens, coyotes, badgers, and ground squirrels are primary predators of Sage Grouse eggs. Avian predators include Golden Eagles, Prairie Falcons, Short-eared Owls, Gyrfalcons, Northern Harriers, goshawks, ravens, crows, magpies, and a variety of hawks including Red-tailed, Swainson's, Rough-legged, and Ferruginous. Ground predators include coyotes, bobcats, minks, badgers, and ground squirrels. Related On-line Sites to Visit
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