• Steam rises off of the colorful Mammoth Hot Springs Terraces


    National Park ID,MT,WY

Mountain Goats

Mountain goats
A group of mountain goats atop the Thunderer.
NPS/Nathan Varley

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 Information Continued...

Quick Facts about Mountain Goats in Yellowstone
  • Non-native species
  • 200 to 300 in and adjacent to Yellowstone
  • Mature male (billy) weighs 300 or more pounds; female (nanny) weighs 150 pounds.
  • Young (kids) born in late May–June.
  • Both sexes have horns; female's curve less and are thinner and sometimes longer than male's.
Additional Resources


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