The diminutive hummingbirds display remarkable manoeuvrability in flight, capable of hovering whilst feeding, with up to 200 wing beats per second. Owing to this energy-demanding behaviour, hummingbirds feed almost exclusively on nectar, the carbohydrate-rich sugar secretions of plants, feeding from as many as 1,000 to 2,000 flowers each day. Hummingbirds also have the highest oxygen requirement of any vertebrate and, as a result, have uniquely structured lungs that enable them to breathe at a rate of up to 500 breaths per minute. These physiological adaptations have allowed hummingbirds to occupy a vast array of habitats and altitudes throughout the Americas (6).
A little studied species, the biology of the chestnut-bellied hummingbird remains largely unknown. However, this tiny bird is thought to feed from the flowers of several plant species, including Salvia and Trichanthera, using its long, specialised tongue to collect nectar from the bottom of the nectaries (2). Breeding pairs form between August and December and, in common with other hummingbirds, males will attract partners with elaborate courtship displays (2) (6). It is also likely that males are territorial and will vigorously defend their home range from intruders (6). Males may mate with several females, but females are responsible for incubating the clutch of two eggs and raising the offspring (2) (6). Once fledged, the young birds may remain fairly sedentary, or undertake nomadic movements in response to seasonal fluctuations in water availability and flowering in key plant species (4).