Natural Histories

Rocky Mountain Goat, Mountain Goat
Oreamnos americanus
Description
Mountain goats have a stout body with a thick white coat (with some brown hairs). Both male and females have thin, black horns (about 200-300 mm long) that have annual growth rings and grow wider in size with age. The horns of a male mountain goat curve back further than those of a female mountain goat. Male mountain goats tend to grow 7.5-15 cm taller than female goats and weigh 61.4- 81.8 kg while females weigh 56.8-70.5 kg.
Habitat
This species can be found from southeast Alaska to Washington, western Montana, and central Idaho. Mountain goats are native to the northern Rocky Mountains but have been introduced to South Dakota, Colorado, and Washington. Mountain goats prefer steep, rocky areas with cliffs or bluffs in alpine or sub-alpine habitats. Steep rocky areas such as moderate slopes, mid-elevations and southern exposures act as escape terrain from predators.
Feeding Behavior and Diet
Mountain goats are herbivores, consuming only plant matter; their main diet consists of grasses, woody plants, mosses, lichens, herbaceous plants, and other vegetation. Water is ingested through the vegetation within the diet or from snow banks.
Reproduction
Males fight with other males for breeding access to females by standing side by side and stabbing the thick skin of their opponent’s flanks with their horns. Males join bands of females to begin courting in September. By October the females have accepted the male into their nursery band. Breeding begins in late November and ends in early January. Females produce 1-3 kids in May-June, about 150-180 days after mating. Females give birth on steep cliffs to deter predators from reaching the kids. Kids are weaned after 3-4 months but remain with their mother until the following year when she gives birth again and chases away the previous young. Males and female mountain goats reach sexual maturity after 30 months.
Months and Times of Activity
This species is active from dawn until mid-day and then again at dusk. During the summer months, this species migrates to high elevations while spending winter months in lowlands. Social banding changes throughout the year. During winter months large bands are formed while summer months are spent solitary or in smaller groups.
Special Features, Stories, Relationships
• Mountain goats dig bedding depressions in the dirt that are about 25-50 mm deep. These depressions are used for dust baths and also to rest during the day and night.
• The age of a mountain goat can be determined by counting the number of growth rings on their horns.
• To read legends featuring this animal go to; http://www.native-languages.org/mountain-goat.htm
• Children’s book featuring this animal: MOUNTAIN GOATS are KIDS like YOU! By Rena Jones
References
Fitch, Juli, Brandi Guilliams, Whitney Mowbray, Allen Patton, Sean Gloss, and Eric J. Ellis.
Ellis, E.; B. Guilliams; W. Mowbray; A. Patton and S. Gloss 2007. "Oreamnos americanus" (On-line), Animal Diversity Web. Accessed November 04, 2014 at http://animaldiversity.ummz.umich.edu/accounts/Oreamnos_americanus/