At Rifle Falls, visitors may observe a variety of bird species due to the diversity of habitats in the area. Northern goshawks and bald eagles are known to spend the winter near the park. Turkey vultures soar among the cottonwoods and boxelders. Other common birds include mountain bluebirds, flycatchers, great blue heron and hairy woodpeckers.
Mule deer, elk, cottontail rabbit, coyote, marmot, least chipmunk and golden-mantled ground squirrel are commonly seen. On rare occasions one may see a black bear or a mountain lion. However, it is more common to see their tracks. Three species of bats live in the cliff faces to the west of the falls. Bullsnake and tiger salamander occur in the park, and East Rifle Creek supports a cold-water rainbow and German brown trout fishery.