Animal life at Petrified Forest includes amphibians, birds, insects, spiders, mammals, and reptiles. Birds, lizards and some rodents are seen most frequently, though seasons and weather play a large role in determining what animals are active. One way to categorize animal life is by what part of the day the animals are most active. Most desert animals are "nocturnal," or active at night. This is an adaptation not only to avoid high summer daytime temperatures, but also to avoid certain predators. Nocturnal animals include kangaroo rats, woodrats (also called packrats) and most other small desert rodents, skunks, foxes, bobcats, bats and owls. Animals that are most active at dawn and dusk are "crepuscular." These times of day are cooler than mid-day and the half-darkness makes prey animals less visible, yet visibility is good enough to locate food. Some animals are crepuscular mostly because their prey is crepuscular and they include pronghorn, mule deer, coyotes, porcupines, desert cottontails, black-tailed jackrabbits, and many songbirds. A few desert animals are primarily "diurnal," most active during the day.
These include pronghorn, squirrels, lizards, snakes, hawks, and Golden Eagles. For many animals, activity occurs during a particular temperature range so they alter their active times of day depending on the season. Snakes and lizards go into an inactive state of torpor during the winter; they are active during the day in late spring and early fall,but they become crepuscular during the heat of summer. Many insects also alter their times of activity. Mosquitoes, for example, may be out at dawn, day, dusk or night depending on the temperatures and moisture. You are much more likely to see animal life at Petrified Forest National Park if you come as early as park hours allow and stay as late as allowed. These are also the times when the angle of the sun makes the views and colors of the Painted Desert most spectacular. 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.