Gunnison sage-grouse | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Galliformes |
Family: | Phasianidae |
Genus: | Centrocercus |
Species: | C. minimus |
Binomial name | |
Centrocercus minimus Young, Braun, C, Oyler-McCance, Hupp & Quinn, 2000 [4] | |
Gunnison sage-grouse range [5] [6] |
The Gunnison grouse, Gunnison sage-grouse or lesser sage-grouse (Centrocercus minimus) is a species of grouse endemic to the United States. It is similar to the closely related greater sage-grouse (Centrocercus urophasianus) in appearance, but about a third smaller in size, with much thicker plumes behind the head; it also has a less elaborate courtship dance. It is restricted in range to southwestern Colorado and extreme southeastern Utah, with the largest population residing in the Gunnison Basin region in Colorado. Despite being native to a country where the avifauna is relatively well known, it was overlooked until the 1990s due to the similarities with the sage grouse, and only described as a new species in 2000—making it the first new avian species to be described from the USA since the 19th century. [7] The description of C. minimus as a separate species is supported by a molecular study of genetic variation, showing that gene flow between the large-bodied and the small-bodied birds is absent. [8]
Gunnison sage-grouse are notable for their elaborate courtship rituals. Each spring, males congregate on leks and perform a "strutting display". Groups of females observe these displays and select the most attractive males with which to mate. Only a few males do most of the breeding. Males perform on leks for several hours in the early morning and evening during the spring. Leks are generally open areas adjacent to dense sagebrush stands, and the same lek may be used by grouse for decades.
This species is in decline because of loss of habitat; their range has shrunk. Following petitions, the species was proposed for listing under the Endangered Species Act by the United States Fish and Wildlife Service, and was eventually protected as a threatened species starting on December 22, 2014. [2] [3] [9] The known population size of this species remains quite small, and it was estimated that fewer than 4,000 individuals existed in when the species was successfully protected under the Act. A 2019 survey found the population in Colorado to be reduced to an estimated 1,800 birds with only around 429 reproductive males, a record low for the species since surveys began. [10]
Gunnison sage-grouse occur in seven counties in southwestern Colorado and one county in southeastern Utah. It was once found in Arizona, New Mexico, and Oklahoma, but is now extirpated in those states.
Males gather on the lek or strutting grounds, which are small, open areas where breeding occurs, in late February to April, as soon as the lek is relatively free of snow. Only a few dominant males, usually two, breed. After mating, the hen leaves the lek for the nesting grounds. Clutch size ranges from six to eight eggs; incubation time is 25 to 27 days. Sage-grouse apparently have high rates of nest desertion and nest predation. Chicks are precocial and can feed themselves. [11]
Gunnison sage-grouse are totally dependent on sagebrush-dominated habitats. Sagebrush is a crucial component of the adult's diet year-round, and they select sagebrush almost exclusively for cover. However, in order to rear a brood of chicks, the young require high protein broadleaved plants and wildflowers that bring insects, also for protein. However, cattle and sheep also relish these plants, and the removal of these critical chick-food plants is a major reason for this bird's decline.
Grouse are a group of birds from the order Galliformes, in the family Phasianidae. Grouse are presently assigned to the tribe Tetraonini, a classification supported by mitochondrial DNA sequence studies, and applied by the American Ornithologists' Union, ITIS, International Ornithological Congress, and others.
Galliformes is an order of heavy-bodied ground-feeding birds that includes turkeys, chickens, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems as seed dispersers and predators, and are often reared by humans for their meat and eggs, or hunted as game birds.
The Phasianidae are a family of heavy, ground-living birds, which includes pheasants, partridges, junglefowl, chickens, turkeys, Old World quail, and peafowl. The family includes many of the most popular gamebirds. The family is a large one and includes 185 species divided into 54 genera. It was formerly broken up into two subfamilies, the Phasianinae and the Perdicinae. However, this treatment is now known to be paraphyletic and polyphyletic, respectively, and more recent evidence supports breaking it up into two subfamilies: Rollulinae and Phasianinae, with the latter containing multiple tribes within two clades. The New World quail (Odontophoridae) and guineafowl (Numididae) were formerly sometimes included in this family, but are now typically placed in families of their own; conversely, grouse and turkeys, formerly often treated as distinct families, are now known to be deeply nested within Phasianidae, so they are now included in the present family.
The black grouse, also known as northern black grouse, Eurasian black grouse, blackgame or blackcock, is a large game bird in the grouse family. It is a sedentary species, spanning across the Palearctic in moorland and steppe habitat when breeding, often near wooded areas. They will spend the winter perched in dense forests, feeding almost exclusively on the needles of conifers. The black grouse is one of two species of grouse in the genus Lyrurus, the other being the lesser-known Caucasian grouse.
The willow ptarmigan is a bird in the grouse subfamily Tetraoninae of the pheasant family Phasianidae. It is also known as the willow grouse and in Ireland and Britain, where the subspecies L. l. scotica was previously considered to be a separate species, as the red grouse. It breeds in birch and other forests and moorlands in northern Europe, the tundra of Scandinavia, Siberia, Alaska and Canada, in particular in the provinces of Newfoundland and Labrador and Quebec. It is the state bird of Alaska. In the summer the birds are largely brown, with dappled plumage, but in the winter they are white with some black feathers in their tails. The species has remained little changed from the bird that roamed the tundra during the Pleistocene. Nesting takes place in the spring when clutches of four to ten eggs are laid in a scrape on the ground. The chicks are precocial and soon leave the nest. While they are young, both parents play a part in caring for them. The chicks eat insects and young plant growth while the adults are completely herbivorous, eating leaves, flowers, buds, seeds and berries during the summer and largely subsisting on the buds and twigs of willow and other dwarf shrubs and trees during the winter.
The western capercaillie, also known as the Eurasian capercaillie, wood grouse, heather cock, cock-of-the-woods, or simply capercaillie, is a heavy member of the grouse family and the largest of all extant grouse species. The heaviest-known specimen, recorded in captivity, had a weight of 7.2 kilograms. Found across Europe and the Palearctic, this primarily-ground-dwelling forest grouse is renowned for its courtship display. The bird shows extreme sexual dimorphism, with males nearly twice the size of females. The global population is listed as "least concern" under the IUCN, although the populations of central Europe are declining and fragmented, or possibly extirpated.
The greater sage-grouse, also known as the sagehen, is the largest grouse in North America. Its range is sagebrush country in the western United States and southern Alberta and Saskatchewan, Canada. It was known as simply the sage grouse until the Gunnison sage-grouse was recognized as a separate species in 2000. The Mono Basin population of sage grouse may also be distinct.
The sharp-tailed grouse, also known as the sharptail or fire grouse, is a medium-sized prairie grouse. One of three species in the genus Tympanuchus, the sharp-tailed grouse is found throughout Alaska, much of Northern and Western Canada, and parts of the Western and Midwestern United States. The sharp-tailed grouse is the provincial bird of the Canadian province of Saskatchewan.
The white-tailed ptarmigan, also known as the snow quail, is the smallest bird in the grouse family. It is a permanent resident of high altitudes on or above the tree line and is native to Alaska and the mountainous parts of Canada and the western United States. Its plumage is cryptic and varies at different times of the year. In the summer it is speckled in gray, brown and white whereas in winter it is wholly white. At all times of year the wings, belly and tail are white. The white-tailed ptarmigan has a diet of buds, leaves, flowers and seeds. The nest is a simple depression in the ground in which up to eight eggs are laid. After hatching, the chicks soon leave the nest. At first they eat insects but later move on to an adult diet, their mother using vocalisations to help them find suitable plant food. The population seems to be stable and the IUCN lists this species as being of "Least Concern".
The Caucasian grouse or Caucasian black grouse is a large bird in the grouse family. It is closely related to the black grouse.
Western Colorado University is a public university in Gunnison, Colorado. It enrolls approximately 2,600 undergraduate and 400 graduate students, with 25 percent coming from out of state.
Denham's bustard, Stanley bustard or Stanley's bustard is a large bird in the bustard family. It breeds in much of Sub-Saharan Africa. It is a species of open ground, including agricultural land, grassland, flood-plains and burnt fynbos. It is resident, but some inland populations move to lower altitudes in winter. The common names for this species refer to the English explorer, Major Dixon Denham, and the English naturalist Edward Smith-Stanley, 13th Earl of Derby.
The helmeted manakin is a species of small passerine bird in the manakin family Pipridae. Unlike most manakins, a family associated with tropical rainforests, the helmeted manakin inhabits the seasonally dry Cerrado savanna of Central Brazil.
Sage-grouse are grouse belonging to the bird genus Centrocercus. The genus includes two species: the Gunnison grouse and the greater sage-grouse. These birds are distributed throughout large portions of the north-central and Western United States, as well as the Canadian provinces of Alberta and Saskatchewan. The International Union for Conservation of Nature classified the C. minimus species as endangered in 2020 and C. urophasianus as near threatened in 2016.
A courtship display is a set of display behaviors in which an animal, usually a male, attempts to attract a mate; the mate exercises choice, so sexual selection acts on the display. These behaviors often include ritualized movement ("dances"), vocalizations, mechanical sound production, or displays of beauty, strength, or agonistic ability.
The Wyoming Basin shrub steppe ecoregion, within the deserts and xeric shrublands biome, is a shrub steppe in the northwestern United States.
Astragalus microcymbus is a species of flowering plant in the legume family known by the common name skiff milkvetch. It is endemic to Colorado in the United States, where it is known from Gunnison County and the edge of Saguache County. It was discovered in 1945 by Rupert Barneby, a British botanist. Currently, skiff milkvetch is experiencing population declines and is listed as a Tier 1 species in the Rare Plant Addendum to the Colorado State Wildlife Action Plan.
Astragalus anisus is a species of flowering plant in the legume family known by the common name Gunnison milkvetch. It is endemic to Colorado in the United States, where it is limited to the Gunnison Basin of Gunnison and Saguache Counties.
This article incorporates public domain material from Centrocercus minimus. United States Department of Agriculture.