Amphibians

Bobcats

Great Basin spadefoot toad and Utah tiger salamander are common in the rim forests. The desert canyons don't seem to be the kind of place you'd expect amphibians, but the permanent tributaries and the Colorado River support red-spotted toads, Woodhouse's Rocky Mountain toad, and canyon treefrogs.

Fish

Non-native fish such as carp and trout dominate the Colorado River because of the artificial cold temperature of the water released from Glen Canyon Dam upstream of the Grand Canyon. These introduced exotics have driven the native squawfish, bonytail chub, and roundtail chub to extinction. Other native fish survive in the warm tributaries such as the Little Colorado River. These include flannelmouth sucker, speckled dace, and bluehead sucker. Surviving but endangered species include razorback sucker and humpback chub.

Insects and Spiders

Common insects of the coniferous forests and desert scrub include wasps, tarantula hawks, honey bees, stink bugs, black flies, beetles, black ants, and butterflies. Scorpions thrive in the lower deserts, while garden spiders, solpugids, wood spiders, black widow spiders, and tarantulas prefer the forests. Insects are common along the permanent streams and the Colorado River, including butterflies, black flies, mayflies, stone flies, beetles, moths, and fire ants. Giant hairy desert scorpions and bark scorpions are also common.