A small green-backed hummingbird of the West that has no brilliant colors on its throat except a thin strip of iridescent purple bordering the black chin, which is only visible when light hits it just right. Black-chinned Hummingbirds are exceptionally widespread, found from deserts to mountain forests. Their breeding range is broad with the highest concentration of birds being in central Texas.
Most often seen at feeders or perched on dead branches in tall trees. This hummingbird is a habitat generalist, found in lowland deserts and mountainous forests, and from natural habitats into very urbanized areas as long as there are tall trees and flowering shrubs and vines and nectar feeders.
Male Black-chins usually arrive on breeding grounds one to two weeks prior to the females to establish territories which they will defend by perching themselves on a high branch to keep watch for intruders. If food supply in their area is abundant, they will share a territory with several other males.
Being small, hummingbirds have a large surface area to volume ratio, thus lose heat quickly, like a car running constantly, but with a very small gas tank. To replace the lost heat energy, hummingbirds must eat great quantities of high energy foods about 15 times an hour. Hummingbirds may consume nectar weighing over 8 times their body weight per day! Because nectar is mostly water, this actually is equivalent to close to their body weight in solid food each day. Hummingbirds will starve to death in just two hours when their engines are running, so at night and other times they cannot feed, they must enter a state of torpor in which they slow down their heart rate and let their body temperature drop close to the outside temperature. During torpor, hummingbirds reduce their energy and water expenditures dramatically, allowing them to survive.
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