Rocky Mountain bighorn sheep, one of four wild sheep species in western North America, inhabit the Central and Southern Rockies, from Alberta to New Mexico. Grazers, they feed on grasses and forbs, favoring steep, sunny slopes; ewes and their young tend to remain at lower elevations of the foothills and mountains while bachelor herds may be found above timberline during the summer months.
Their annual rut, featuring head-on collisions of the 400-pound rams, peaks in December and is best witnessed in foothill canyons, below 9000 feet. These duels determine breeding rights and, after this seasonal frenzy, all spend the winter in peaceful coexistence. Impregnated females give birth to a single lamb (twins are rare) in late May or June, by which time the rambunctious males have moved to higher ground. The lifespan of the Rocky Mountain bighorn averages 10-12 years but their gregarious lifestyle makes them susceptible to outbreaks of parasitic disease, especially lungworm pneumonia; others die from falls or from predation by humans, mountain lions or coyotes.
There are many places to observe the bighorn rut throughout Colorado; some of the more reliable locations along the Front Range include Waterton Canyon (southwest of Denver), Mueller State Park (west of Colorado Springs), along I-70 (across from Georgetown) and Big Thompson Canyon (U.S.34, west of Loveland). Regardless of where you go, bring warm, layered clothing and binoculars; be aware that dogs are not permitted in Waterton Canyon.
