Violet-bellied hummingbird

Adult:

• The male violet-bellied hummingbird is more brightly colored than its female counterpart.[2] Its breast and belly is a violet blue while its back, crown, and throat is a metallic green.[2] While the rump is more of a bronze green.[2] The retrices are a blue black while the belly and undertail coverts are a dull black with a blue/green sheen.[2] Around the tibia are white tufts which are framed by partly white spots on its belly.[2] The feathers on its wings are dusky with a purple sheen.[2] On average males are 7.5 cm long and weigh 3.4 g.[7][2]
• The female violet-bellied hummingbird is more dull than its male counterpart.[2] Though its back, crown, and throat, is a similar metallic bronze green, its belly is a pale gray rather than a bright violet.[2] Its rump and uppertail coverts are more bronze than green while undertail coverts are a dull brown gray.[2] The retrices can also be a blue black or a blueish green, and the outer retrices are tipped with pale gray.[2] Similar to the males, the females' wings are dusky with a purple sheen.[2] Commonly in subspecies panamensis, the sides of the throat may be spotted with metallic green.[2] On average females are 7 cm long and weigh 3.0 g.[2][7]

Juvenile plumage has only been documented for immature males. They appear similar to an adult female although they may have some patches of violet on their belly or a sparkling green foreneck.[2][6]

The molt pattern of this species is also yet to be described.

Violet-bellied hummingbirds are very easily confused with woodnymphs.[2] The green crowned woodnymph, in particular, has a similar color and shape and their ranges overlap.[8] To tell them apart, you must check their size, color, and tail; violet-bellied hummingbirds are smaller, their backs are green instead of violet, and their tails are rounded, not notched.[2] Green crowned woodnymphs also have a violet forecrown.[2] Another similar species is the Sapphire-throated Hummingbird because of its colors.[2] However, it has a blue throat, a green belly, and a notched tail.[2]

As with many species of hummingbirds, violet-bellied hummingbirds seem to be polygynous.[2] Males mate with multiple females and attract them by singing on perches about 1–10 m high.[2] They may also fly in a 'u' shape in front of the females.[9] However, after mating, they leave the female to rear the young.[9] Individuals do not mate for life nor do they aggregate in flocks.[9]

The females are responsible for creating nests and rearing the young.[9] She creates a nest from plant fibers, animal hair and feathers in a shrub or a tree, approximately 1.2 to 4.2 m above ground.[9][2] She will then incubate the clutch of two white eggs, each 8 by 13 mm.[2] Incubation lasts 15 days followed by a 20-22 day nestling period.[2] The chicks are altricial when they hatch and thus rely on their mother to feed and defend them.[9] If successful, violet-bellied hummingbirds go on to live for approximately 4.2 years.[10]

Violet-bellied hummingbirds are primarily considered nectarivorous but may more accurately be called omnivorous.[2] They consume nectar from plants in the Rubiaceae, Ericaceae, Gesneriaceae (Besleria), and Fabaceae (Inga) families.[2] They also eat small arthropods, as do many other species of hummingbirds.[2] Males may defend their feeding territory from other males and large insects.[9] Although violet-bellied hummingbirds do not form flocks, they may congregate at fruit trees and feeders.[8] The violet-bellied hummingbird's predators are not known.

According to their IUCN Red List conservation status of least concern, the violet-bellied hummingbird does not seem to be threatened.[10] They are tolerant to disturbed areas such as forest edges.[2]