Scientific Name: Oreamnos americanus
In 1993 the Colorado Wildlife Commission proclaimed the mountain goat a native species. However, most professional biologists doubt that the animals ever occurred in Colorado naturally. Some early travelers reported goats in Colorado, but none of those reports is absolutely reliable. Side-by-side, mountain goats and bighorn sheep look very different, but from a distance a person might mistake a bighorn female for a goat, because bighorn ewes have prominent, gently curved horns. Even today, visitors to Colorado’s high country often identify bighorn sheep as “mountain goats.” A bone from an extinct species of mountain goat was found in fossil deposits about 800,000 years old in Porcupine Cave, South Park.
With their shaggy white wool coats and black horns, these are beautiful and distinctive animals. Billies range to five feet long and weigh up to 250 pounds; nannies are somewhat smaller. Both sexes have sharp, black horns, six to 12 inches long.
They mostly stay in their high mountain range year around, seldom going below treeline, except in severe winter weather.
Mountain goats eat grasses, mosses, lichens, and some shrubbery. They tend to eat more broad-leafed plants than do bighorn sheep.
Kids are born in May or June after a gestation period of about six months. Twins occur in about a quarter of all births. Typically half of a local population is made up of yearlings. Because of the mountain goat’s inaccessible habitat, mountain lions are one of their few predators. Rockslides or avalanches probably cause most deaths. Mountain goats provide hunters with a challenging hunt, after drawing a license in one of several goat hunting units.
By David M. Armstrong Department of Ecology & Evolutionary Biology Environmental Studies Program, University Museum of Natural History University of Colorado-Boulder