The chestnut-bellied hummingbird distribution appears to be restricted to the dryer parts of the Magdalena Valley, Colombia, with a core known range in the Chicamocha, Suárez and Chucurí river valleys. Even though there are now sites where it is known to be found, it is unpredictable in occurrence because of the unknown seasonal fluctuations. It spends the core of its range in dry valleys. Recent records have found it in more humid areas such as the Chucurí near San Vicente de Chucurí and La Paz. Otherwise it has been found in Tipacoque, and a sighting in 2006 at Soatá and has been recorded in five municipalities including a rediscovered population in the environs of Soatá. The sightings seem to be around the range of above sea level because they like to habituate in places which are usually dry, but due to its current relocating it can now also be found in humid environments as well. It seems to be a nomadic species as certain suitable habitats have gone unrecorded for periods whilst it seems to be resident in others. The increased sightings of the bird has been due to the increased efforts by observers and the link that might have been made between the flowering events and their reliance on this. The population is estimated at 3,780 individuals, by extrapolating its known territory size by the area of suitable habitats. However, since many suitable habitats aren't occupied by these and they are not evenly distributed, this may represent an overestimate.
Habitat and Ecology
Most of the places that this rare and endangered species likes to live is recorded to be around humid places; however, it was recently discovered that they prefer to live near rivers and streams that run through the forest. Although the habitat is slowly being damaged by humans, it handles the decrease in its living conditions, and gradually adapts to new areas. Since humans have been destroying its environment in the woods, the chestnut-bellied hummingbird it has been seen in places such as farms, fruit crops, and coffee plantations. These new ecosystems that it lives in allows it to expand its range from just typical Amazonian plants and flowers to plants such as cactuses, bananas, and coffee. However although it has expanded its common habitat to these new places, the most frequently visited tree by the hummingbird remains to be the Nacedero Tree. Since there has been so much human exploitation, the birds have not only adapted themselves to new environments, but surprisingly prefer the new adapted environments to the original; however, that does not mean that they completely close off the original ecosystems. Breeding season for these birds ranges between the months of December to February which is the same time as bee-keeping season. The fact that they are bred at the same time helps the hummingbird because it creates an environment in there is a lot of honey in the ecosystem which helps them breed more easily.
Identification
The chestnut-bellied hummingbird is small with reddish-brown underparts and tail. It has a grey rump and shining green throat and chest. Its legs are small and white while it has a black bill and pinkish base to lower mandible. Amazilia castaneiventris is very similar to amazilia tzacatlexcept for the tzacatl's underparts being dingy grey. The amazilia castaneiventris makes a distinguished “grr-grr” when defending its territory from conspecifics or other hummingbirds.
Threats
The chestnut-bellied hummingbird is located in the dense population region of Colombia. In the past twenty or so years, there has been expansive economic growth, due to a gold rush in 1996 and also the increasingly profitable business of deforestation. Not only are the forests being cut down, but also sugar and coffee plantations are replacing them. Decreased habitats and increased pollution and human migration accompanied these new industries. Although these businesses are benefitting the Colombian economy, they are by far the largest threats to the habitat of the endangered bird.
Miscellaneous
Birds are often associated with the sounds and calls that they make. Hummingbirds are no different. The different calls that they make allow people to understand what they are saying or doing.
