|Distribution map of the cactus wren.|
The cactus wren primarily eats insects, including ants, beetles, grasshoppers, termites and wasps. Occasionally, it will take seeds, fruits, small reptiles and frogs. Foraging begins late in the morning and is versatile; the cactus wren will search under leaves and ground litter and overturn objects in search of insects, as well as feeding in the foliage and branches of larger vegetation. Increasing temperatures cause a shift in foraging behavior to shady and cooler microclimates, and activity slows during hot afternoon temperatures. Almost all water is obtained from food, and free-standing water is rarely used even when found.
It is a bird of arid regions, and is often found around yucca, mesquite or saguaro; it nests in cactus plants, sometimes in a hole in a saguaro, sometimes where its nest will be protected by the prickly cactus spines of a cholla or leaves of a yucca.
In residential areas, cactus wrens are notorious for getting into mischief. Being curious birds, it is not uncommon for them to be found flying about out-of-place in automobiles or homes where a window has been left open.