The buff-bellied hermit hummingbird (Phaethornis subochraceus) is a small hummingbird species found in Central and South America. With an average body length of 11-12 cm and weight of 5-8 grams, it is a relatively large hermit hummingbird. This species gets its name from the buff or cinnamon colored underside of the males. Females and juveniles are less colorful, with more white undersides.
Range and Habitat
The buff-bellied hermit has a wide range across Central and South America. Its northern limits reach southern Mexico, with its range extending south through Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, and down into northern Columbia. Its southern range stretches through Venezuela, the Guianas, Ecuador, Peru, Bolivia, and Brazil.
This species inhabits tropical and subtropical humid lowland forests, forest edges, second growth forests, plantations, and gardens. It has adapted well to disturbed habitat and can thrive in areas with human settlement. It mainly resides in foothill areas up to 1200 m in elevation but may be found up to 1600 m.
The buff-bellied hermit hummingbird exhibits sexual dimorphism. Adult males have a vibrant green back and crown, with glittering emerald green throat feathers. The underside is a buff or cinnamon color. The tail is rusty cinnamon with a bold black subterminal band. Females are less vibrant, with a golden olive green back. The throat is buff colored with small dark spots. The cinnamon colored tail has weaker barring. Juveniles resemble adult females.
These hummingbirds have long, needle-like bills adapted for accessing nectar from flowers. Their tapered wings allow great maneuverability and hover capability. Short legs provide little mobility on the ground. They have unique tubular tongues for sucking up nectar.
Diet and Feeding
The buff-bellied hermit hummingbird primarily feeds on nectar from flowers using its specialized tongue. It favors flowers with long corollas where it can access the nectar with its elongated bill while hovering. Some favorite nectar sources include heliconias, gingers, and bromeliads.
This species also consumes small insects and spiders, which provide an important source of protein. Aerial insects are captured during flight. The hermit will also glean insects from foliage in a methodical manner, searching leaves and branches.
The breeding season of the buff-bellied hermit aligns with the rainy season, which varies across its wide range. In Central America this occurs between May to August while in South America breeding takes place September through December.
Males establish and defend small breeding territories with plentiful nectar sources. Their iridescent throats are used in courtship displays to visiting females. Once paired, the female builds a small cup nest out of plant fibers, lichen, and spider webs on a low tree branch. She incubates the two tiny white eggs for 15-19 days. Nestlings fledge in roughly 20-26 days. Females provide all parental care.
Roosting and Torpor
To conserve energy overnight, the buff-bellied hermit uses torpor – a state of decreased physiological activity. It will find a protected roosting spot on a branch and lower its metabolic rate and body temperature. Periodic shallow torpor may also be used during the daytime if food is scarce.
With a wide range and substantial global population, the buff-bellied hermit hummingbird is evaluated as Least Concern on the IUCN Red List. Deforestation and habitat loss in parts of its range are potential ongoing threats. The adaptability of this species allows it to thrive in disturbed areas, provided there are adequate flowers, perches, and nest sites. This resilience helps offset population declines in sensitive forest areas.
– The buff-bellied hermit exhibits traplining behavior – visiting a regular circuit of productive flowers. An individual may defend this trapline territory.
– To reduce heat loss overnight, these hermits fluff out their plumage to trap a layer of air against their body.
– Dominant males will chase rivals out of their breeding territory in fast pursuit flights.
– The long bill of this species helps it steal nectar from flowers with longer corollas. This is called “robbing” and often damages the flower.
In summary, the buff-bellied hermit hummingbird is a fascinating tropical species adapted to hovering and feeding on nectar. With vibrant colors and specialized behaviors, it is an integral pollinator in its Central and South American range. While some threats exist, robust populations ensure this hermit continues to thrive.