Mammals are a diverse group of animals which share several characteristics: warm blood, fur or hair, and production of milk for their offspring. Forty-five species of mammals are known to live in Petrified Forest National Park. Some animals, like desert cottontails, kangaroo rats and pronghorn, are very common and frequently seen by visitors. In the high plateau of northeast Arizona, mammals have a variety of survival strategies. Physiologically, some mammals have developed hollow hairs which serve as insulation. Behaviorally, some hide in their burrows, migrate, or are nocturnal, using the night to survive the heat of summer or to escape notice of predators. Rodents are numerous at Petrified Forest National Park. Because of their size, these animals are less able to migrate, but have an easier time finding shelter and require less food and water to live. One rodent uniquely adapted to life in an arid climate is the kangaroo rat. It never drinks water.
The dry seeds it eats metabolize to provide the moisture needed within its body. Specialized kidneys allow the disposal of waste with very little loss of water. However, even the kangaroo rat chooses to spend the hottest daylight hours sleeping in a cool underground burrow and may even plug the opening with dirt or debris for insulation. Kangaroo rats are often seen crossing roads at night, balancing with their furry tails as they hop on elongated hind legs. Another rodent, the prairie dog, lives in large colonies or "towns." Each town is divided into areas called wards, which are further divided into social groups called coteries. In each coterie there will be an adult male, several females, and their offspring. As prairie dogs browse for forbs or grass, designated guards watch for danger. The guards' high-pitched cries announce the approach of predators, sending the town's inhabitants running for their burrows. Prairie dogs are a favorite food source for coyotes, hawks, golden eagles, foxes, badgers, and bobcats. Another popular prey for predators is the black-tailed jackrabbit. Jackrabbits are actually hares, not rabbits. Unlike rabbits, jackrabbits don't build nests and their young are born with eyes wide open, ready to go. To escape their predators, jackrabbits dash away in an explosion of speed, their zigzagging route broken by long leaps.
They can sometimes be seen resting in the shade of a sage or saltbush. In the heat of summer their ears act as air-conditioners; blood vessels in the long, thin ears exchanging heat with the surrounding air. A flying mammal, the pallid bat is one of the many bat species found in the Southwest. They are best recognized by their pale coloring, blond fur and pink faces. Insectivores, they are an important part of the environment, eating hundreds of arthropods during the night including beetles, centipedes, moths, cicadas, praying mantises, grasshoppers, crickets, and even scorpions. Their acrobatic flight is a pleasure to watch. Larger mammals, like pronghorn and coyote, must cover much territory in order to find food and water. Though pronghorn are frequently called antelope, they are actually the sole living survivor of an ancient family of animals, Antilocapradae. The fastest mammal in North America, elegant pronghorn can sprint up to 60 miles per hour. They are frequently seen in the park's grasslands, traveling alone or in small herds. Opportunistic foragers, pronghorn feed on forbs, shrubs, grasses, juniper, and sometimes even cacti.
During late spring and into summer, look for the gangly offspring of the pronghorn shadowing their mothers. Coyotes are the ubiquitous symbol of the west. This gray and tawny predator is a member of the canine family. Coyotes help control rodents, which make up a large percentage of their diet. They are true omnivores, eating whatever they can find including fruits, reptiles, insects, small mammals, birds, and carrion. Coyotes are often seen crossing the park roads early in the morning and if you acquire a permit to hike and overnight in the wilderness, you will likely hear their lonely howls in the night. Early morning is the best time to view most of the mammals while in the park. Whenever you are in a national park, do not approach, feed, or harass any wildlife. Help your parks reduce the impact of human visitors to the homeland of many wild species.