The sheep usually roam in small social units, either maternal ewe, lamb and yearling groups, or groups of rams. Sheep forage is limited by the cool temperatures and nutrient poor soils of the northern alpine environment. Under these conditions, the sheep mature slowly and have low reproductive rates. Females reach breeding age at three to four years and produce only one lamb per year. Males breed when their horns are large enough for them to establish a dominant position in the ram hierarchy, usually at seven to nine years.
Winter weather is the main factor that affects Dall sheep numbers.
In sheep habitat, temperatures normally stay below freezing, snowfall is light, and winds sweep many ridges and slopes, keeping snow cover light. These conditions allow the sheep good access to winter forage. However heavy snows, temporary thaws, and freezing rains can create a frozen barrier preventing the sheep from digging for the plants. Dall sheep walk a survival tightrope, although they do it rather effectively. They have lived since the Pleistocene in places such as the Arctic Refuge.