The mountain cottontail, Sylvilagus nuttalli, generally occupies areas above 6,000 feet in elevation.
Cottontails grow up to 16 inches in length with ears three to four inches long, and weigh less than three pounds. They are grayish or brownish on the back and sides with white below. The top of the tail is similar in color to the rump but it is prominently white underneath; thus the name cottontail.
Cottontails are widely distributed from desert areas up to the lower slopes of the mountains. Concentrations commonly occur in brushy areas along stream courses or dry washes.
Cottontails eat a wide variety of forbs, grasses, and shrubs.
Four to seven young are born after a 28 day gestation. Three or more litters can be weaned annually. Their nest is usually a chamber in an underground burrow.
Cottontails are distinguishable by their relatively small size, short ears, and white tail.