CSIRO Publishing, Emu - Austral Ornithology, 3(111), p. 252
DOI: 10.1071/mu10032
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Limited food availability disrupts the energy balance of animals, and nectarivorous birds with high metabolic requirements that necessitate frequent feeding may be particularly affected. We kept White-bellied Sunbirds (Cinnyris talatala) and Brown Honeyeaters (Lichmera indistincta) at 10°C, fed them a 0.63-M sucrose solution, and exposed them to a 2-h fasting period at midday. Food intake increased following the fast, relative to uninterrupted feeding. A comparison with the maximal intake predicted by a digestive capacity model showed that both species fed at maximal levels in the hour following the fast. Although the short-term feeding pattern of the Honeyeaters was not investigated, the Sunbirds increased the duration of meals immediately after the fast, followed by a non-significant increase in meal frequency. In contrast to published data for hummingbirds, these two passerines accumulated energy at higher rates after the fast than on the control. However, food intake over the whole day was lower on the fasting day and birds weighed less in the evening compared with the control, indicating that the compensation of energy accumulation was incomplete. The two species from phylogenetically distinct nectarivorous avian taxa show similarities in their response to fasting periods, possibly owing to similar feeding behaviour and physiological constraints. ; Angela Köhler, Luke Verburgt, Patricia A. Fleming, Todd J. McWhorter and Susan W. Nicolson