The three most common amphibians in the Grand Canyon are the canyon treefrog, red-spotted toad, and Woodhouse's rocky mountain toad. These amphibians need the Colorado River or perennial tributaries in order to breed, since their egg masses and tadpoles are water bound. However, they are more tolerant of desiccation than most amphibians, and red-spotted toads have been found as far as one-half mile from a known water source. Leopard frogs are very rare in the Colorado River corridor, and are known to exist at only a few sites.
Amphibians are generally absent from dry desert upland areas that are more than one mile from water.
The Utah tiger salamander and the Great Basin spadefoot toad are two amphibians that are common in the rim forests. They live in the North Rim's moist grasslands near ponds or stock tanks and in more mesic habitats on the South Rim. The Arizona tiger salamander and the Great Plains toad are more rare and are seldom seen.