Their song is a loud raspy chirrup; akin in the description of some ornithologists to the sound of a car engine that will not start.

It is well-adapted to its native desert environment, and the birds can meet their water needs from their diet which consists chiefly of insects, but also of some plant matter.

Its common name derives from their frequenting desert cactus plants such as the saguaro and cholla, building nests, roosting, and seeking protection from predators among them.

Pairing among cactus wrens is monogamous; in each breeding season, the males chiefly build nests, the females incubate eggs, and both parents feed the young.

Feral cats hunt many birds in urban settings, and invasive grasses take up valuable foraging space, reducing habitat size.

The population still numbers in the millions, leading the International Union for Conservation of Nature to consider the cactus wren a species of least concern.

Study of the evolution of the cactus wren suggests that it evolved in central Mexico about one million years ago and quickly spread to its modern range.

[9] However, Lafresnaye did not know that, and thought the specimen – which he called Picolaptes brunneicapillus – might have come from Peru (far outside the range of the wren), as the officer had stopped there on his journey.

Matters were not helped by ornithologist John Gould, who described the cactus wren – as Thryothorus guttatus – independently in 1836 and also failed to say precisely where his specimen had come from.

[3] The cactus wren's ten primary and nine secondary flight feathers are barred, alternating between black and off-white.

[5] Other distinctive features of juveniles include the lack of a white nape streak, and less noticeable black chest markings.

[3] Summer often takes a harsh toll on plumage; the intense desert sun and prickly vegetation fade and damage feathers.

The main call of the cactus wren is a harsh and raspy series of jar-jar-jar,[3] or char, notes, which increase in volume and pitch as the song goes on.

[21] Males begin singing before dawn and prefer to vocalize from high vantage points, such as trees, telephone poles, tall cacti, or roofs.

The main call is made while the beak is held just slightly above horizontal, and makes the feathers on the bird's throat noticeably extend from their normal position and vibrate.

[5][10]: 32 The cactus wren is a bird of arid and semi-desert regions, and generally requires spiny cacti to nest in.

Its range in Arizona is widespread in the southern part of the state and along the Colorado River,[5] where it is found from sea-level up to 1,400 m (4,600 ft).

[5] Cactus wrens generally feed and live in pairs,[23] or in family groups from late spring through winter.

[14] There is a distinctive greeting ceremony between pair members, where they spread their wings and tails and give a harsh call.

[14] Since males and females are identical, birds recognize members of the opposite sex not by size or color but by behavioral differences.

[24] Nests are built in cacti (commonly cholla, prickly pear, and saguaro), thorny desert trees, or yucca.

[20][23] Nests built in urban settings use a much wider variety of materials, including many human made items such as paper, string, and lint.

[5] Cactus wrens usually lay three or four eggs (although as many as seven have been recorded) which are smooth and ovate, colored white to pale pink[3] and covered in brown speckles.

[5] Cactus wrens also sip nectar from saguaro blossoms and eat insects trapped within, serving as pollinators in the process.

The same study found that Neoschoengastia americana, the turkey chigger, affects birds during late summer and early fall.

[27] Cactus wrens share a similar range to the curve-billed thrasher, as well as the jumping cholla, a favored plant for both species to nest in.

[1] Current population estimates put the species at about seven million individuals, with slightly more than half in Mexico, and the balance in the United States.

[5] Coastal populations in southern California face threats due to habitat loss as a result of suburban development.

Study has shown that fire has a large impact on cactus wrens due to their territoriality, with populations persisting only in unburned pockets.

These issues are compounded by the apparently poor ability of the cactus wren to disperse: each subsequent generation will usually not travel far to establish a territory.