Like all desert dwellers, amphibians have adapted to the hot, arid environment of the Colorado Plateau. Amphibians, which include frogs, toads, and salamanders, are cold-blooded, or poikilothermic, meaning they regulate their body temperature through external sources rather than by internal metabolism. They have moist, soft skin that aids in temperature, moisture, and gas regulation. Because of these characteristics, amphibians cannot tolerate extreme heat or drought, both common to the desert. In general, amphibians are most active during the warmer months of the year (May to October) and may become more active in the early morning, twilight, or night during hot summer months to conserve energy and moisture. During the day they rest in shady cracks in the rock, underground, or in other dark, damp places. Amphibians require high amounts of moisture for survival and reproduction, and most species in Glen Canyon National Recreation Area (NRA) are found in or near water sources. In 2003, an inventory of amphibians and reptiles documented five amphibian species present in Glen Canyon NRA. Future surveys may increase the number of observed species.
The canyon treefrog (Hyla arenicolor) is common around the shores and side canyons of Lake Powell and can be found clinging to sandstone walls near water during the day. Canyon treefrogs have a wide distribution throughout the Colorado Plateau and prefer intermittent or permanent streams with rocky bottoms. This species can be identified by its small size, grayish somewhat bumpy skin, and toe pads.