Centrocercus minimus
Male and female Gunnison sage grouse look different. Males have white chests with two round yellow air sacs on their chests. The sacs have feathers like scales which they blow up like little balloons in spring. This helps them attract mates. Males have black bellies and a white V-shaped area between their throat and chest. They also have spiky brown and white tail feathers that they fan out as part of courtship. Females are smaller, lighter, and have gray-brown feathers. Females have shorter tail feathers, and don't have air sacs like males. Chicks look a lot like females and have brown and white speckled feathers. Gunnison sage grouse in southwestern Colorado have shorter and narrower beaks than they do in northern Colorado. Gunnison sage grouse look a lot like greater sage grouse, but these are smaller and have longer feathers on their heads. They are usually 32 to 51 cm long, have a wingspan of 6 to 76 cm, and weigh 990 to 2435 g. ("Gunnison Sage Grouse", 2004; Sohl, 2012; Young, et al., 2012)
Gunnison sage grouse are native to North America, and live in southwestern Colorado and southeastern Utah. The number of them has declined a lot. Now, there are only five groups left, which are called populations. Scientists have tried to introduce them to New Mexico, Oregon, Montana, Wyoming, Utah, Colorado, and Idaho, but haven't been very successful. Gunnison sage grouse only live in a small part of the area where they could live. This is probably because of changes to their habitat. (Grother, 2012; McWilliams, 2002; Schroeder, et al., 2004; Young, et al., 2012)
Gunnison sage grouse need habitats with sagebrush and other grasses when mating, nesting, and raising their chicks. They are found in sagebrush and next to water that they use for food and finding protection. Some groups of sage grouse stay in the same location all year, while others move between winter and summer locations. A third group moves between different locations in winter, summer, and for mating. Gunnison sage grouse usually choose places without many plants when they are mating. They live from 2,200 to 4,300 m in elevation. ("Gunnison Reservoir", 2012; Connelly, et al., 2000; Falsetto, et al., 2011; Schroeder, et al., 2004; Young, et al., 2012)
Male Gunnison sage grouse compete for female mates. Between mid-March and late May, males travel to competition spots called leks. These leks have low plants and sagebrush, so females can see them easily. Males make popping noises with their air sacs and strut around for hours, walking back and forth across the area. They might also fan out their tails. Gunnison sage grouse often go back to the same spot every year. Males defend their lek from outsiders. Females prefer to mate with males that make the same courtship noises as other males that live close to them. Only one or two of the competing males is able to mate with the watching females, and very young males are almost never able to breed. ("Determination for the Gunnison Sage-grouse as a Threatened or Endangered Species", 2010; McWilliams, 2002; Young, et al., 2012)
Females take care of laying the eggs, hatching the chicks, and raising them. From late March to April, females look for good nesting sites. They prefer places with a variety of plants, which makes better food and more protection. Plants called forbs have calcium, phosphorous, and proteins that help develop healthy eggs. Gunnison sage grouse nest from mid-April to June, and females may travel a long ways to find a good nesting spot. They look for spots with enough plant cover to protect them from predators, and come back to the same place ievery year. ("Determination for the Gunnison Sage-grouse as a Threatened or Endangered Species", 2010; McWilliams, 2002)
Females lay 6 to 8 eggs that take 25 to 27 days to hatch. They don't lay very many eggs at one time, but most of them hatch in June. Chicks weigh about 30 g and are pretty well developed. They soon leave the nest and move to somewhere along the water where they eat insects. Chicks can fly a little bit after they are 2 to 3 weeks old and can feed themselves. They are much better at flying by the time they are 5 to 6 weeks old. Sometimes, they follow their mothers around until the fall. The chicks are independent of their mothers at 10 to 12 weeks old. In the winter, male chicks split off from female chicks and their mothers. ("Determination for the Gunnison Sage-grouse as a Threatened or Endangered Species", 2010; McWilliams, 2002)
Males don't help females build nests or raise their chicks. They look for places to nest that are well protected, and have the right kinds of plants with proteins and phosphorous. Females go back to the same place to nest if they are successful there. Chicks follow their mothers around after they hatch, but mothers don't put too much effort into caring for them. The chicks actually get most of their food themselves. ("An Animal of the High Desert - Greater Sage Grouse", 2011; McWilliams, 2002)
Gunnison sage grouse live 3 to 6 years in the wild. The oldest they can live is 9 years. They are difficult to raise in captivity, and usually live only about 1 year. It is harder for males to survive than females because they are bigger and the colors of their feathers stand out more. ("Encyclopedia of Life", 2012)
Gunnison sage grouse are social birds that travel in groups called flocks. They spend most of the day eating, grooming their feathers, and stretching. They start the day by searching for food. They relax until evening, and then start looking for a place to spend the night. They spend about 60% of the day foraging for food. They will travel a long ways to find food and protection. In the winter, males and females live in separated groups, but they sometimes sit in the sun together to stay warm. In the spring, the groups come back together to mate, and males compete for females. Older males often attract more mates. In the summer after most of the eggs hatch, the mothers and chicks look for food together. Even though their bodies are heavy, Gunnison sage grouse are pretty good at flying. They can fly as fast as 50 mph. This is especially important because they have short legs and aren't very good at flying. (McWilliams, 2002; "Sage Grouse Initiative", 2012)
Researchers in Utah tracked how far Guinnson sage grouse traveled between summer and winter from 2002 to 2004, and measured the size of their home range. The distance they traveled between summer and winter was 2.4 km to 5.9 km. The size of the area where they lived and looked for food was 2.4 to 2.8 sq km. The numbers were different for males and females. (Ward and Messmer, 2006)
Gunnison sage grouse communicate by calling, making noises during courtship, and signaling with their feathers. They use calls to defend territories, or alert others about a threat. Females decide their mates based on noises made during courtship, so males look for a spot in the arena that makes their sound seem the loudest. During this courtship process, males also communicate about their territories by chasing other males or fighting them. They also signal to each other by spreading their tail feathers or flapping their wings. (Patricelli, 2010; Young, et al., 2012)
Gunnison sage grouse eat different things depending on their age and the season. In early summer, chicks eat insects and flowering plants called forbs. Insects give the chicks lots of protein so they can grow and develop. In late summer, chicks start to eat forbs, and then sagebrush. In the colder months, sagebrush dries out and both chicks and their parents eat forbs and sagebrush that grows alongside water. In fall and winter, they eat mostly sagebrush. They don't have very strong digestive muscles in their stomachs, so they have trouble digesting seeds. ("Gunnison Sage Grouse", 2004; "Sage Grouse Initiative", 2012)
Gunnison sage grouse are easy for predators to eat because they are large and can't run very fast. Males are not very well camouflaged, and are not very difficult for predators to see. Females and chicks are smaller, have better camouflage, and are less likely to get eaten by a predator. Gunnison sage grouse are more likely to get eaten by predators when the number of black tailed jackrabbits is low. Other places, the number of regular prey has decreased and Gunnison sage grouse are now eaten more often. When there are lots of tall plants, nests are better protected from predators. Animals that often prey on their nests are coyotes, ground squirrels, and American badgers. Finally, Gunnison sage grouse are hunted and eaten by humans. This is now illegal in Colorado and Utah because their numbers have declined so much. ("Encyclopedia of Life", 2012; McWilliams, 2002; "Sage Grouse Initiative", 2012)
Gunnison sage grouse graze on plants. Light or moderate grazing can be good for the plants and insects that live on them, but too much is bad for them. They also get infected with some kinds of blood parasites. (Gibson, 1990; Prather, 2010)
Gunnison sage grouse and ranchers need the same kind of habitat, so they might compete with livestock for habitat. However, their relationship is mostly good for both of them. (Prather, 2010)
Gunnison sage grouse may be a keystone, or very important, species in their environment. They need the same kind of habitat that ranchers do. This means that when ranchers sell off their land, the kind of habitat good for Gunnison sage grouse gets split up, and it is more difficult for them to survive. ("Sage Grouse Initiative", 2012)
Gunnison sage grouse are Endangered according to the IUCN Red List of Threatened Species. They are endangered in Michigan as well. Their problems are break-up of their habitat, invasive plants, and the plants being all the same. Some organizations are working to protect Gunnison sage grouse. For example, the Colorado Parks and Wildlife is working with the Colorado Cattlemen's Association, Gunnison County, and the Bureau of Land Management to research what is important for the survival of Gunnison sage grouse. They are trying to conserve land where the sage grouse live. In 2010, the US Fish and Wildlife Service stated that the species is not a top priority endangered species, but are important because of their role in the ecosystem. This has helped protect some Gunnison sage grouse habitat. ("BLM Colorado Sage-grouse Conservation Effort", 2012; "Canadian Sage Grouse Recovery Strategy", 2001; "Sage Grouse Initiative", 2012)
Gunnison sage grouse were not considered their own species until the 1990s, because they behave in a very similar way to greater sage grouse. They are actually different because of the bodies, genes, and the way they mate. ("Encyclopedia of Life", 2012)
Priscilla Kuo (author), The College of New Jersey, Matthew Wund (editor), The College of New Jersey, Catherine Kent (editor), Special Projects.
2011. "An Animal of the High Desert - Greater Sage Grouse" (On-line). Idaho National Library. Accessed October 29, 2012 at http://www.gsseser.com/Newsletter/archive/Sagegrouse.htm.
2012. "BLM Colorado Sage-grouse Conservation Effort" (On-line). Bureau of Land Management. Accessed October 29, 2012 at http://www.blm.gov/co/st/en/BLM_Programs/wildlife/sage-grouse.html.
2001. "Canadian Sage Grouse Recovery Strategy" (On-line). Accessed October 04, 2012 at http://www.srd.alberta.ca/FishWildlife/SpeciesAtRisk/LegalDesignationOfSpeciesAtRisk/RecoveryProgram/documents/SageGrousePlan.pdf.
Fish and Wildlife Service. Determination for the Gunnison Sage-grouse as a Threatened or Endangered Species. FWS-R6-ES-2009-0080. MO: National Archives and Records Administration. 2010. Accessed November 14, 2012 at http://www.fws.gov/mountain-prairie/species/birds/gunnisonsagegrouse/75FR59804.pdf.
2012. "Encyclopedia of Life" (On-line). Centrocercus Minimus: Gunnison Sage Grouse. Accessed October 29, 2012 at http://eol.org/pages/900212/details.
2012. "Gunnison Reservoir" (On-line). Water Quality Utah. Accessed November 14, 2012 at http://www.waterquality.utah.gov/watersheds/lakes/GUNNISON.pdf.
2004. "Gunnison Sage Grouse" (On-line). All About Birds. Accessed October 29, 2012 at http://www.allaboutbirds.org/guide/Gunnison_Sage-Grouse/lifehistory.
Sage Grouse Initiative. 2012. "Sage Grouse Initiative" (On-line). Accessed October 29, 2012 at http://sagegrouseinitiative.com/content/behavior.
Connelly, J., M. Schroeder, A. Sands, C. Braun. 2000. Guidelines to manage sage grouse populations and their habitats. Wildlife Society Bulletin, 28/4: 967-985. Accessed November 14, 2012 at http://sagemap.wr.usgs.gov/Docs/Sage_Grouse_Guidelines.PDF.
Falsetto, R., J. Soceka, J. Sowell, A. Stork. 2011. "Western State Colorado University" (On-line). Digital Land-Cover Map of the Gunnison Basin. Accessed November 14, 2012 at http://www.western.edu/academics/geology/research/landcover/digital-land-cover-map-of-the-gunnison-basin.html.
Gibson, R. 1996. Female choice in sage grouse: the roles of attraction and active comparison. Behavioral Ecology and Sociobiology, 39/1: 55-59. Accessed November 04, 2012 at http://www.springerlink.com/content/68wyw9qflmy27duh/.
Gibson, R. 1990. Relationships between Blood Parasites, Mating Success and Phenotypic Cues in Male Sage Grouse Centrocercus urophasianus. Amer. Zool., 30/2: 271-278. Accessed November 04, 2012 at http://icb.oxfordjournals.org/content/30/2/271.short.
Grother, C. 2012. "Uncompahgre Plateau Project" (On-line). Gunnison Sage Grouse. Accessed October 23, 2012 at http://www.upproject.org/plateau/grouse.htm.
McWilliams, J. 2002. "Centrocercus minimus, C. urophasianus. In: Fire Effects Information System" (On-line). Accessed October 17, 2012 at http://www.fs.fed.us/database/feis/animals/bird/cent/all.html#BiologicalDataAndHabitatRequirements.
Patricelli, G. 2010. "Research Interests" (On-line). Accessed October 29, 2012 at http://www.eve.ucdavis.edu/gpatricelli/Patricelli_Research_Interests.html.
Prather, P. 2010. "Factors Effecting Gunnison Sage Grouse (Centrocercus Minimus) Conservation in San Juan County, Utah" (On-line). Accessed October 17, 2012 at http://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1823&context=etd&sei-redir=1&referer=http%3A%2F%2Fwww.google.com%2Furl%3Fsa%3Df%26rct%3Dj%26url%3Dhttp%3A%2F%2Fdigitalcommons.usu.edu%2Fcgi%2Fviewcontent.cgi%253Farticle%253D1823%2526context%253Detd%26q%3DCentrocercus%2Bminimus%2Blifespan%26ei%3Dt2B_UPDnFMjp0QG9nYH4Cw%26usg%3DAFQjCNG80TT1c9ilSFjTf067nOIaMGzPvw#search=%22Centrocercus%20minimus%20lifespan%22.
Schroeder, M., C. Aldridge, A. Apa, J. Bohne, C. Braun, J. Connelly, P. Deibert, S. Gardner, G. Kobriger, S. McAdam, C. MCCarthy, J. McCarthy, D. Mitchell, E. Rickerson, S. Stiver. 2004. Distribution of Sage-Grouse in North America. The Condor, 106.2: 363-376. Accessed October 04, 2012 at http://www.bioone.org/doi/abs/10.1650/7425.
Sohl, T. 2012. "Gunnison Sage-Grouse" (On-line). South Dakota Birds and Birding. Accessed October 29, 2012 at http://sdakotabirds.com/species/gunnison_sage_grouse_info.htm.
Ward, S., T. Messmer. 2006. "Gunnison Sage-grouse Winter and Summer Ecology in San Juan County, Utah" (On-line). Accessed November 04, 2012 at http://utahcbcp.org/files/uploads/sanjuan/SWOGREPORT2006.pdf.
Young, J., C. Braun, S. Oyler-McCance, J. Hupp, T. Quinn. 2012. A New Species of Sage Grouse from Southwestern Colorado. The Wilson Bulletin, 112 (4): 445-453. Accessed October 04, 2012 at http://newweb.western.edu/faculty/jyoung/files-documents/Young%20et%20al%202000.pdf.