[3][4] It has pale yellow eyes highlighted by thin white "eyebrows" and a gray bill with a horn-colored tip.

The elf owl frequently inhabits woodpecker holes in saguaro cacti; it also nests in natural tree cavities.

[6] The elf owl was formally described in 1861 by the American naturalist James Graham Cooper from a specimen collected near Fort Mohave in Arizona.

He coined the binomial name Athene whitneyi, choosing the specific epithet to honour the geologist Josiah Whitney.

[16] The distinctive vocalizations of elf owls vary according to sex, with males exhibiting a wider repertoire of complex notes as opposed to females of the same species.

Most avian observers refer to "Class A" songs to describe those that vary in length (generally 5–15 notes), and are used as both territorial proclamation and to herald the arrival of males to females in the area.

Class B functions as the primary mating call, stimulating females and encouraging them to accept male sexual advances.

There are also a handful of locational, so-called "scolding", and territorial songs belonging to both male and female birds of the elf owl species.

Some broods of elf owl migrate to the southwest United States (California, Arizona, New Mexico, and Texas) in the spring and summer for breeding.

Elf owls usually choose abandoned, north-facing woodpecker cavities in saguaro cacti, sycamores, cottonwoods, and other hardwood trees, to raise their young.

During this time, females engage in the singing of locational calls (see Description for more information on elf owl vocalizations), and males respond with mating rituals of their own.

The destruction of habitat leaves many elf owls unable to nest, hunt, and reproduce in areas like California, Arizona, and elsewhere.

California has implemented a captive breeding program in an attempt to increase this number, while numerous environmental and government agencies work to preserve their riparian and desert homes.

[23] An elf owl named Gylfie is a major character in the Guardians of Ga'Hoole book series by Kathryn Lasky, and the 2010 film adaptation.