The Gunnison grouse, Gunnison sage-grouse or lesser sage-grouse (''Centrocercus minimus''), is a species of

grouse Grouse are a group of birds from the order Galliformes, in the family Phasianidae. Grouse are presently assigned to the tribe Tetraonini (formerly the subfamily Tetraoninae and the family Tetraonidae), a classification supported by mitochondr ...

endemic to the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. It is similar to the closely related

greater sage-grouse The greater sage-grouse (''Centrocercus urophasianus''), also known as the sagehen, is the largest grouse (a type of bird) in North America. Its range is sagebrush country in the western United States and southern Alberta and Saskatchewan, Canad ...

(''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 Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...

and extreme southeastern

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

, with the largest population residing in the Gunnison Basin region in Colorado. Despite being native to a country where the

avifauna Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweight s ...

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. 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.

Breeding

Gunnison sage-grouse are notable for their elaborate courtship rituals. Each spring, males congregate on

leks A lek is an aggregation of male animals gathered to engage in competitive displays and courtship rituals, known as lekking, to entice visiting females which are surveying prospective partners with which to mate. A lek can also indicate an avail ...

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 Sagebrush is the common name of several woody and herbaceous species of plants in the genus ''Artemisia''. The best known sagebrush is the shrub ''Artemisia tridentata''. Sagebrushes are native to the North American west. Following is an alph ...

stands, and the same lek may be used by grouse for decades.

Conservation

This species is in decline because of

loss of habitat Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...

; their range has shrunk. Following petitions, the species was proposed for listing under the

Endangered Species Act The Endangered Species Act of 1973 (ESA or "The Act"; 16 U.S.C. § 1531 et seq.) is the primary law in the United States for protecting imperiled species. Designed to protect critically imperiled species from extinction as a "consequence of ec ...

by the

United States Fish and Wildlife Service The United States Fish and Wildlife Service (USFWS or FWS) is an agency within the United States Department of the Interior dedicated to the management of fish, wildlife, and natural habitats. The mission of the agency is "working with othe ...

, and was eventually protected in 2015. 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.

Distribution

Gunnison sage-grouse occur in seven counties in southwestern Colorado and one county in southeastern Utah. It was once found in

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ...

, and

Oklahoma Oklahoma (; Choctaw language, Choctaw: ; chr, ᎣᎧᎳᎰᎹ, ''Okalahoma'' ) is a U.S. state, state in the South Central United States, South Central region of the United States, bordered by Texas on the south and west, Kansas on the nor ...

, but is now

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

in those states.

Lifecycle

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. Johnsgard, Paul A. (1973). Grouse and quails of North America. Lincoln, NE: University of Nebraska Press .

Preferred habitat

Gunnison sage-grouse are totally dependent on

-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.

References

{{Taxonbar, from=Q1261158

Gunnison grouse 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 appearanc ...

Birds of the Great Basin Endemic birds of the Western United States

ESA threatened species