Over 27 species of mammals have been observed on the refuge. Visibility of mammals varies greatly due to the nocturnal habits of some and to seasonal hibernation. Watch for coyotes, blacktail jackrabbits, desert cottontails, and white-tailed antelope squirrel. Desert bighorn sheep are occasionally observed at Point of Rocks and Devil's Hole.

In the spring, baby desert cottontails hop along the edges of the open areas. These rabbits have adapted to handle the hot summers. Their light-colored fur keeps them cool, while their large ears help release heat like a car's radiator.

In summer, antelope ground squirrels are often seen with their white tails up over their backs, acting like a sunshade to keep them cool. This unique desert animal's body temperature can go up to 110 F. To cool off, they lay down and stretch out their bodies on their burrow floor.

As weather begins to cool, bobcats may become more active during daylight hours. These carnivores (meat-eaters) can run up to 30 miles per hour, making them difficult to see.

Winter brings a welcome surprise as desert bighorn sheep come to the Point of Rocks Springs to drink. They are able to survive in the desert for as long as 8 days without water; then drinking nearly 5 gallons at one time.