The midget faded rattlesnake, Crotalus oreganus concolor, is a subspecies of the western rattlesnake that is found in western Colorado, eastern Utah, and southern Wyoming. Midget faded rattlesnakes are primarily found on the ground, but will occasionally climb into trees and shrubs. When inactive during cold weather, individuals occupy mammal burrows, crevices, or caves, where they sometimes congregate in large numbers.
The midget faded rattlesnake is live-bearing; females give birth to approximately four to twelve young in the late summer or fall. The diet of this species consists of small mammals, birds, lizards, and occasionally amphibians. Prey are subdued by injecting venom through large hollow fangs at the front of the upper jaw. This rattlesnake is typically tan, cream, or yellowish in color, with faint oval blotches on the back. The midget faded rattlesnake is usually less than 24 inches in length.