Hummingbirds
Calypte costae
The Costa's Hummingbird is a diminutive and compact species found in arid regions of southwestern North America. Males are easily identified by their striking iridescent purple crown and gorget, which flares dramatically. Females are more subtly colored, with green upperparts and whitish underparts. This species is well-adapted to desert environments, often timing its breeding with the availability of desert blooms.
Typical adult measurements.
Individuals and populations vary.
01 / The telltale details
Start with shape and behavior. Then look for the smaller details.
Iridescent violet-purple crown and a gorget that flares out along the sides of the neck. Back and flanks are metallic green.
Greenish upperparts, whitish underparts, and a pale eyebrow stripe. Lacks the male's extensive purple iridescence.
Resembles the adult female, with greenish upperparts and whitish underparts. May have gray-buff edging on upperpart feathers.
Small and compact with a hunched posture and a relatively short tail.
02 / A place in the world
Costa's Hummingbirds prefer arid and semi-arid environments, including Sonoran and Mojave Desert scrub, coastal California chaparral, and sage scrub. They are often found in desert washes with flowering plants like chuparosa and ocotillo, and can also be seen in gardens and open meadows.
This species breeds in the southwestern United States, primarily in Southern California, southern Nevada, southwestern Utah, and western Arizona, and extends into northwestern Mexico, including the Baja California Peninsula and Sonora. Some populations winter along the Pacific coast of Mexico.
Costa's Hummingbirds are considered residents or short-distance migrants, with movements often driven by the availability of nectar. Birds breeding in the Sonoran and Mojave Deserts typically move towards coastal areas in summer and fall to find abundant flowers.
03 / Listen a little closer
The male's song is a high-pitched, shrill whistle, often given during courtship dives and from perches. Females vocalize more frequently, with high-pitched calls indicating food, predators, or during mating rituals.
04 / The life behind the feathers
Their primary diet consists of nectar from a variety of desert plants, such as chuparosa, ocotillo, and various sages. They supplement their diet with small flying insects, which they catch in mid-air or glean from vegetation, to meet protein requirements.
These hummingbirds typically feed while hovering at flowers, extending their bill to access nectar. They also catch small insects in mid-air or pluck them from foliage. Males defend territories around prominent perches and nectar sources during the breeding season.
The female alone constructs a small, cup-shaped nest from plant fibers, bark strips, small leaves, and lichen, bound with spider silk. Nests are usually placed 1-2 meters (3-7 feet) above the ground in shrubs or small trees. She lays two white eggs and incubates them for 15-18 days.
Costa's Hummingbirds are generally solitary, though males perform elaborate aerial courtship displays to attract females, involving high-speed dives and loops. They can enter a state of torpor to conserve energy during cold nights, significantly slowing their heart rate.
One more reason to pay attention
A Costa's Hummingbird may need to visit approximately 1,840 flowers daily to meet its energy demands.
This species was a foundational subject in early research on hummingbird torpor, a state similar to hibernation.
The species was named in honor of Louis Marie Pantaléon Costa de Beauregard, a French nobleman and ornithologist.
05 / An eye for the difference
Anna's Hummingbirds are larger and chunkier, with a rose-pink (rather than purple) crown and gorget. Their tail extends further past the wings when perched.
Black-chinned Hummingbirds appear plainer and more slender. Males have a black throat with a narrow iridescent purple band below it, lacking the extensive purple crown and flaring gorget of the Costa's.
Calliope Hummingbirds are smaller than Costa's. Male Calliopes have a streaky magenta gorget that does not extend to the crown or flare as dramatically as the Costa's.
AI-assisted species research. Prepared September 2026. Details can vary across regions and populations.