Mountain Goats

Four mountain goats on top of a mountain

Mountain goats are not native to the Greater Yellowstone Ecosystem.



Descendants of mountain goats (Oreamnos americanus) introduced in Montana during the 1940s and 1950s, established a population in the park in the 1990s and have reached a relatively high abundance in the northeastern and northwestern portions via the Absaroka and Gallatin mountain ranges. Investigations of paleontological, archeological, and historical records have not found evidence that the mountain goat is native to Greater Yellowstone.

Many people consider the goats a charismatic component of the ecosystem, including those who value the challenge of hunting them outside the park. But the colonization has raised concerns about the goats’ effects on alpine habitats. Competition with high densities of mountain goats could also negatively affect bighorn sheep, whose range overlaps that of mountain goats. Learn More: Mountain Goat Habitat...


Quick Facts
Nonnative species

Number in Yellowstone

208 in and adjacent to Yellowstone

Where to See

  • Infrequently seen; northeastern and northwestern portions of the park in alpine habitat.
  • Winter: steep, south-facing slopes, windblown ridgetops;
  • Spring: south- and west-facing cliffs;
  • Summer: meadows, cliffs, ravines, and forests.

Behavior and Size

  • Mature male (billy) weighs 300 or more pounds;female (nanny) weighs 150 pounds.
  • Young (kids) born in late May–June.
  • Females usually begin to breed at 2½ years.
  • Live in precipitous terrain.
  • Both sexes have horns; females curve less and are thinner and sometimes longer than males.

More Information

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