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.
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).
Anita Trussler (author), Fresno City College, Carl Johansson (editor), Fresno City College.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
uses sound to communicate
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.
uses smells or other chemicals to communicate
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
uses sight to communicate
Baker, C. 2001. "Costa Rica, Birds" (On-line). Accessed October 18,2000 at http://photo.net/cr/moon/birds.html.
Cassidy, J. 1990. Book of North American Birds. Pleasantville, NY: Reader's Digest Association, Inc..
Dawson, W. 1923. The Birds of California. San Diego: Southern Moulton Company.
DeGraaf, R., V. Scott, R. Hamre, L. Ernst, S. Anderson. November 3, 1998. "Forest and Rangeland Birds of the United States" (On-line). Accessed October 13,2000 at http://www.npwrc.usgs.gov/resource/1998/forest/forest.htm.
Gough, G., J. Sauer, M. Iliff. 1998. "Patuxent Bird Identification Infocenter Version 97.1.: Black-chinned Hummingbird" (On-line). Accessed September 18, 2000 at http://www.mbr-pwrc.usgs.gov/Infocenter/infocenter.html.
Peterson, R. 1961. A Field Quide to Western Birds. Cambridge: The Riberside Press.
Terres, J. 1980. The Audubon Society Encyclopedia of North American Birds. New York: Alfred A. Knopf Inc..
del Hoyo, J., A. Elliott, J. Sargalal, eds.. 1999. Handbook of the Birds of the World, Vol. 5. Barn-Owls to Hummingbirds. Barcelona: Lynx Edicions.