Both male and female mountain goats have beards, short tails, and long black horns, 15–28 cm in length, which contain yearly growth rings.
Male goats also have longer horns and a longer beard than nannies.
The mountain goat’s feet have inner pads that provide traction and cloven hooves that can be spread apart as needed. Also, the tip of their feet have Dewclaws that are sharp to keep them from slipping.
Mountain goats are herbivores and spend most of their time grazing. Their diet includes grasses, herbs, sedges, ferns, moss, lichen, twigs and leaves from the low-growing shrubs
In the wild, mountain goats usually live twelve to fifteen years, with their lifespan limited by the wearing down of their teeth.
Kids are born in the spring (late May or early June) after a six month gestation period.
Although they are mostly weaned within one month, kids follow their mothers closely for the first year of life
Mountain goats reach sexual maturity at about thirty months. Nannies in a herd undergo synchronized estrus in late October through early December. Mature billies will stare at nannies for long periods, dig rutting pits, and fight each other in showy scuffles. After the breeding season is over, males and females move away from each other, with the adult billies breaking up into small bands of two or three individuals. Nannies form loose-knit nursery groups of up to 50 animals.
Nannies can be very competitive and protective of their space and food sources. They will fight with one another for dominance in conflicts that can ultimately include all the nannies in the herd. In these battles, nannies will circle each other with their heads lowered, showing off their horns. To avoid fighting, an animal may show a posture of non-aggression by stretching low to the ground.