Cynanthus latirostrisbroad-billed hummingbird

Geographic Range

Broad-billed Hummingbirds Cynanthus latirostris are found primarily in northwestern Mexico. They do occasionally range into southern Arizona, southwest New Mexico and west Texas in the spring and summer. They are also occasionally reported in Southern California. (Terres 1980;US Distribution and Abundance 2000).

Habitat

The Broad-billed Hummingbird is common in Mexico as well as in south-western United States. They tend to live and nest in areas such as canyons, foothills and streambeds. Their distribution in any particular area is closely tied to the availability and abundance of appropriate food plants. (Sayre,1999; Terres, 1980).

Physical Description

Broad-billed Hummingbirds are considered a small hummingbird. Their average length is 8.25 - 10.2 cm (31/4 - 4 inches) long, with a wingspread of approximately 12.7 cm (5 inches). The males weigh about 3.7 grams (0.125 oz), while the females are a little lighter at 3.4 grams (0.1 oz). Broad-billed Hummingbirds have a bright red bill with a black tip. The adult males have metallic green bodies, vibrant blue throats, white undertail coverts and black forked tails. The adult females have metallic green upper parts and grayish throats and undersides. Their tails have pale outer tips. Most distinguishing about the female is the thin white spot behind her eye.

The method in which hummingbird wings are attached to the shoulder allows the wings to move in various angles, enabling the hummingbird to hover, fly straight up, sideways, and even backwards. This unique method of flight requires large flight and pectoral muscles, which weigh about 30 percent of their body weight. The hummingbird's wing beat is approximately 70-75 beats per second (Page and Morton 1989; Sayer 1997; Terres 1980).

  • Range mass
    3.4 to 3.7 g
    0.12 to 0.13 oz

Reproduction

Broad-billed Hummingbirds breed from January to May in Mexico and in the United States from April to August. Breeding season is closely tied to the flowering season of some plants. Broad-billed Hummingbirds are polygynous, meaning that males have more than one mate at the same time. Males who defend a territory are more successful than "floaters" (those without a territory) at attracting females. The males attract females with songs, and their songs tend to be very simple in design. When the female respond to the advertising male, it usually results in copulation. The female then builds the nest. The nests are mainly built in trees or large scrubs approximately 1.22 - 2.13m (4-7 feet) above the ground, and are usually found near streambeds or a dry wash. Material used to make the nests may include grasses, leaves, bark and other plant material. Once the nest is complete, the female will lay one to two elongated, white eggs. She incubates the eggs from 14-23 days, and rears the young without the assistance of the male. (Campbell 1985; Martin 1987; Perrins 1985; Sayre 1999; Terres 1980).

Lifespan/Longevity

Behavior

In general, aggressive behavior of hummingbirds includes threat vocalizations, dives, and chasing of intruders. Most aggressive behavior is associated with territorial defense. Male hummingbirds typically defend feeding territories as well as breeding sites, and females defend nesting sites. A large percentage of the male's time and energy is used to defend his territory . Such defense usually begins in the air. It can include clawing, pushing, even using their bill as a weapon.

It was believed at one time that hummingbirds sucked the nectar through their bills. It is now proven that they use their forked-tongue to lap nectar from flowers.

Many kinds of hummingbirds sometimes enter into short states of torpor, which is used to conserve their energy and lower their metabolism. This usually happens when the night temperature is low or if the hummingbird has low food reserves. The average body temperature of the hummingbird is 41 degrees Celsius (105 degrees Fahrenheit). During torpor, a hummingbird's body temperature will lower to about the same temperature as the air. In a state of torpor, their approximate metabalic rate is 1/50 of that of an alert hummingbird. Hummingbirds in this state can appear dead. Their metabolism rate is so reduced that they may actually stop breathing for a short period of time (Perrins 1985; Sayre 1999).

Communication and Perception

Food Habits

The diet of the Broad-billed Hummingbird is primarily nectar from flowers such as the red blossoms of Ocotillo and Paintbrushes. They eat sugar-water from hummingbird feeders as well. Because of their metabolic rate, it is not uncommon for them to eat five to ten times an hour. As a result of their high-energy output, hummingbirds need to consume 1 ½ - 3 times their body weight in nectar each day. Broad-billed Hummingbirds also need protein; therefore they are known to eat many insects such as aphids, leafhoppers, bugs, and root gnats. Hummingbirds will consume more water in a day than solid foods (Sayre 1999; Terre 1980).

Economic Importance for Humans: Positive

Broad-billed Hummingbirds pollinate many flowers. As a result, this helps to support the ecomonic growth of the ornamental horticulture industry.(Page and Morton 1989)

Conservation Status

In the nineteenth century, hundreds of thousands of hummingbirds were killed in South America and sent to England to be used as decorations. Some individuals would have the colorful birds stuffed and placed on display in their homes. Many were used in the design and decoration of women's hats. It has been reported that up to 400,000 skins were imported in a single year by one London dealer.

(Martin 1987)

Currently, there are numerous non-profit groups who are dedicated to the study and protection of hummingbirds, for example the Hummer/Bird Study Group http://www.hbsg.org and the Hummingbird Society http://www.hummingbird.org.

Contributors

Christy Platt (author), Fresno City College, Carl Johansson (editor), Fresno City College.

Glossary

Nearctic

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.

World Map

acoustic

uses sound to communicate

bilateral symmetry

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.

chaparral

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.

chemical

uses smells or other chemicals to communicate

desert or dunes

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.

endothermic

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.

iteroparous

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).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

visual

uses sight to communicate

References

2000. "US Distribution and Abundance" (On-line). Accessed September 18, 2000 at http://www.i-bird.com/Species/BroadbilledHumgbrd.htm.

Campbell, B., E. Lack. 1985. A Dictionary of Birds. South Carolina, USA: Buteo Books.

Jones, J. 1990. Where The Birds Are- A Guide to All 50 States and Canada. New York, New York: William Morrow and Company, Inc..

Martin, B. 1987. World Birds. Great Britain: Guinness Superlatives Ltd..

Page, J., E. Morton. 1989. The Smithsonian Book of Birds Lords of the Air. New York: The Smithsonian Institute.

Perrins, C., A. Middleton. 1985. The Encyclopedia of Birds. New York, New York: Facts on File, Inc..

Sauer, J. 7/27/97. "USGS Patuxent- Bird Population Studies" (On-line). Accessed 10/9/00 at http://www.mbr.nbs.gov.

Sayre, J., A. Sayre. 1996. The Sun Catchers- Hummingbirds. Minnetonka, Minn: Creative Publishing International.

Terres, J. 1980. The Audubon Society Encyclopedia of North American Birds. New York, New York: Alfred A. Knopf.