Archilochus alexandri
black-chinned hummingbird

The Black-Chinned Hummingbird, Archilochus alexandri, has the most extensive breeding range of all northwestern hummingbirds. It regularly occurs throughout western North America, from as far north as British Columbia south to northern Mexico, and from coastal California to central Texas, where its population is highest in density. During the winters, the Black-chin migrates to southern California, southern Arizona, southern Texas and Mexico (Peterson 1961; Gough et al. 1998).

Although Black-Chinned Hummingbirds are territorial, they are willing to share a desirable territory, as long as the food supply is abundant. The Black-chinned Hummingbird usually nests between 1-2.5m, (4-8 feet) high and often over water. In early summer Black-chins can be found at the bottom of foothill canyons. They will remain in the area until late summer when the food supply of flowers ends. Then, Black-chins will migrate to higher elevations, sometimes 1829-2591m to follow the late flower season. Black-chins also live in semi-wooded canyons, chaparral, and foothill suburbs (Terres 1980; Peterson 1961; Dawson 1923).

Black-chins are sexually dimorphic, meaning that the male and female look different from one another. As with other species of hummingbirds the male is the more brightly colored and distinctive than the female. The male can be identified by its black face. Its chin and upper throat area are also black, but the lower throat area is an iridescent blue-violet. This is bordered by a white collar below. The back and crown of the male is a metallic green color. The tail feathers of the male are black. The females have the same bright green back and crown, but differ by its green face, white breast and throat area with a few black spots. The female Black-chin also has white tips on the outer feathers of her tail. Both sexes have a white spot behind their eyes and a straight long thin bill. The Black-chinned Hummingbird is considered a small hummingbird, its length measuring 9.0 to 9.5cm. Females are usually larger than the males, they weigh on average about 3.5 g., the male average weight is 3.0 g. (Dawson 1923; Terres 1980).

The nest is built in about 3 days by the female Black-chin. She selects a drooping branch of a bush or a fork in a tree limb for the nest. The female collects the down of young sycamore trees or other plants and binds them together with spider webs to give the nest an elastic, feltlike quality. The small, deep cuplike nest measures about 3.5cm (1.5 inches) in diameter. The nest is able to stretch to double its size as the young grow and need more room. Two to three tiny eggs are laid sometime between early April to the end of September. They measure on average, 12 x 8mm. Newly laid eggs are white with a pinkish tint, changing later to a dull white or gray color right before they hatch. The incubation period usually lasts 13-16 days. The offspring usually fledge after about 20 days (Cassidy 1990; Dawson 1923).

Hummingbirds are typically loners, they associate with the opposite sex only for the few seconds it takes to mate. During courtship, the male Black-chin swoops and dives in a shallow arc to impress his mate, he also sings a soft, high-pitched warble. Black-chins, like most hummingbirds, are very territorial, and will defend both food sources and breeding or nesting areas. Male Black-chins usually arrive one to two weeks prior to the females to establish feeding areas. They guard their territories by perching themselves on a high branch to keep watch for intruders, they also give a vocal warning to competitors. For those who ignore the warnings, an excited chippering sound can be heard when Black-chins are chasing other birds during these defensive "intimidation" flights.

During the winter months, Black-chins migrate to southern California, Arizona, Texas and Mexico. In order to survive the migration, between 800-1600km, the Black-chin must store up extra fuel. Before migrating they must increase their body weight by 25-50% (del Hoyo et al. 1999; Terres 1980; Baker 2001).

The diet of the Black-chinned Hummingbird consists of nectar, pollen, insects and sugar water from feeders. The black-chin prefers nectar from flowers of Tree Tobacco Nicotiana glauca, Scarlet Larkspur Delphinium cardinale, and Desert Ocotillo Fouquieria splendens. Black-chins dart out into the open to catch flying insects or gleans them from foliage to provide the protein necessary for proper development of their young (Terres 1980; DeGraaf et al. 1998).

The Black-chinned hummingbird may play a role in the pollination of various species of plants.

Unknown

The Black-chinned Hummingbird was given its species name in 1846, after a medical doctor, M. M. Alexandre, who collected birds in Mexico. This species was named in his honor by Bourcier and Musant in France. (Terres 1980).