Last Updated on Monday, 14 December 2009 13:58
Common Name: Mountain Goat
Also referred to as: Rocky Mountain Goat, Snow Goat, White Goat
Genus species: Oreamnos americanus
Recognized subspecies: Mountain Goats were previously classified into four subspecies; however, no subspecies are currently recognized
- Weight: Mid-summer, males weigh 95-115 kg; females weigh 60-75 kg.
- Length: Males are 155-180 cm in total length; females are 140-170 cm.
- Sexual dimorphism in body mass; males are often 40-60% heavier than females.
- They have stout bodies, short tails and a thick dermal shield protecting the rump.
- Their legs are short as well, and very muscular.
- Their hooves are two-toed, with a stiff outer edge and flexible central pad; they have well developed dewclaws that provide grip when descending along a steep rock face.
- The horns are short, black and recurved, with basal annulations and smooth tips; horn length is nearly equal for both sexes.
- Their pelage is long, coarse and cream-white in colour, sometimes with a yellowish tinge.
- Winter coats include a 3-5 cm thick layer of wool beneath the long guard hairs; the winter coat is shed between May and August, with the next winter coat already underway. The summer moult can be used to sex mountain goats in July. Males shed their coat earlier and have a smooth coat, whereas females shed later and still look shaggy during July.
- The hair is mane-like along the dorsal ridge, and their beard grows with increased age.
- Dental formula: I(0/3), C(0/3), P(3/3), M(3/3).
North American Distribution:
- In Canada, O. americanus is found throughout the Rocky Mountains, between Alberta and British Columbia, as well as the coastal mountain range of British Columbia and the Yukon.
- In the USA, O. americanus has maintained native populations within Alaska, Washington, Montana and Idaho; Mountain Goats have been introduced to Colorado, Oregon, Nevada, South Dakota, Utah and Wyoming.
- Within Alberta, O. americanus is found within the Rocky Mountain and Foothill Natural Regions.
- Preferred habitat includes areas that provide escape terrain, including steep cliffs (45-60o), bluffs, rocky outcrops, talus slopes at the base of cliffs within Alpine tundra and subalpine sub-regions.
- Snow generally covers the ground 8-9 months of the year.
- They rely on alpine meadows for foraging; however, they rarely venture far from the escape terrain of rocky cliffs.
- Adult males commonly forage below the tree line within coniferous forests; adult females with juveniles rarely travel below the tree line.
- During winter, Mountain Goats prefer to use lower elevation habitats to avoid deep snow, often foraging at or below the tree line.
- Bedding sites are often located near or on cliffs where individuals have a clear view of their surroundings; they use their front hooves to dig bedding site into 3-10 cm of soft ground.
- Competition for bedding sites is common and neighbours are often only 1-4 m away.
- Annual home range size is approximately 21 km2 and 24 km2 for males and females, respectively.
Movements and Migratory Habits:
- Mountain Goats are somewhat gregarious; however, less so than Mountain Sheep, Ovis canadensis.
- Daily activities alternate between foraging and resting-ruminating with 6-7 feeding-resting cycles every day.
- Mountain Goats are most active at dawn and dusk; however they are also active throughout the day and night.
- Adult males travel less than 1 km/day; adult females travel 2-5 km/day, potentially more when in nursery groups.
- Winter movements are often of shorter distances than summer movements due to deep snow.
- Seasonal migrations do occur in some populations; however, others utilize the same area throughout the year.
- In some populations, males do travel extensively during the rut; this depends on the distance between neighbouring groups, for Mountain Goats do not have particular rutting ranges.
Diet and Foraging Strategy:
- Mountain Goats are considered intermediate feeders, consuming a variety of both grass/forbs (grazer) and woody plant (browser) forage types. Their diet consists of fescue, bluegrass, wheatgrass, hairgrass, sedges, rushes, bluebells, willows, birch and sagebrush. The same generalized diet is consumed year round, with a slight shift in the types of plants consumed from 55% grasses, 30% forbs and 15% browse in the summer to 60% grasses, 10% forbs and 30% browse in the winter.
- Aggressiveness between individuals does occur when forage is scarce.
- Salt licks are an important component of their diet; traditional salt licks are returned to throughout the summer.
- Mountain Goats will travel long distances to reach these salt licks and aggressive interactions are common once they are there.
- The rut occurs between late October and early December.
- Males are polygamous, defending females and rutting territories from other males with attempts to stab their horns into the other’s flanks and rump.
- The gestation period is approximately 190 days.
- Parturition is highly synchronized and occurs between mid May and early June; each female has 1-2 kids (twins occur 25% of the time, triplets are rare) within a two week period.
- Females isolate themselves within a rocky outcrop or cliff prior to giving birth.
- Kids weigh approximately 2.5-3.5 kg at birth; growth rate averages 195 g/day.
- Within a few days, the kids are able to follow their mother wherever she goes.
- Kids are weaned at four months of age.
- The female will remain with her kid for up to a year.
- Females reach sexual maturity at four years of age, on average (3-7 years).
- Males reach sexual maturity after one year.
- Federal Status: Not listed.
- Provincial Status: Secure.
- Predation is not a major factor influencing Mountain Goat survival; the most significant causes of death are avalanches, falls and starvation during adverse weather conditions.
- The largest threat to their population is road development and the associated disturbances.
Mountain Goat photo © 2007 Paul Tessier. Retrieved from www.istockphoto.com/stock-photo-3635404-mountain-goat.php on 22/09/09. Used with permission.
Alberta Sustainable Resource Development (ASRD). 2008. Search Species and Status Category. <http://www.srd.alberta.ca/BioDiversityStewardship/SpeciesAtRisk/GeneralStatus/StatusOfAlbertaWildSpecies2005/Search.aspx>. Accessed 21 October 2009.
Cote, S. D., and M. Festa-Bianchet. 2003. Mountain Goat. Pages 1061-1094 in G.A. Feldhamer, B.Thompson, and J. A. Chapman, editors. Wild mammals of North America: biology, management and conservation. Second edition. Johns Hopkins University Press, Baltimore, Maryland, USANowak, R.M., and J. L. Paradiso.1983. Walker’s Mammals of the World. Forth edition. Volume 2. John Hopkins University, Baltimore, Maryland, USA.
Forsyth, A. 1999. Mammals of North America: Temperate and Arctic Regions. Firefly Books, Buffalo, New York, USA.
Government of Canada. 2008. Species at Risk Public Registry. <http://www.sararegistry.gc.ca/sar/index/default_e.cfm>. Accessed 21 October 2009.
Jasper Environmental Association. 2009. Mountain Goats: living on the edge. <http://www.jasperenvironmental.org/mountain-goats.htm>. Accessed 24 October 2009.
Yaki, G. J. 2009. Mountain Goat, Oreamnos americanus. Talk About Wildlife. <http://talkaboutwildlife.ca/profile/index.php?s=501>. Accessed 24 October 2009.