The monument's sagebrush steppe landscape appears ideal habitat for rattlesnakes, but they are not found here. Why? We don't know. Prairie rattlesnakes inhabit other parts of Wyoming at elevations over 8500 feet, but usually are restricted to elevations less than 7,000 feet.
Did You Know?
The Green River Formation includes the best paleontological record of Tertiary aquatic communities in North America and possibly the world.