Until the age of about three, males and females look exactly the same... and then the horns begin to grow. Males grows horns made of keratin, and they may be as old as eight years before a full horn spiral is completed. Females also grow horns, but they are shorter and much more slender.
Ewes are pregnant for about 175 days (roughly 5.7 months) and give birth to one lamb. These lambs grow quickly and are weaned after 3-5 months. Ewes typically breed every year.
Dall Sheep are listed as being of Least Concern.