Energy regulation by traplining hummingbirds

1. A published model of constant diurnal energy accumulation by territorial hummingbirds does not accurately reflect the temporal distribution of feed ing behaviour of traplining hummingbirds, Phaethornis longirostris (Long-Ta iled Hermit Hummingbirds), 2, In an enclosure study, gross nectar intake by P. longirostris decreased through the day, mirroring nectar production rates in its natural food-flow ers and mimicking its natural foraging patterns. 3. Using a simulation model, the energetic consequences of constant and dec reasing net energy intake rates for traplining hummingbirds are compared, 4. Given natural patterns of nectar production, model birds with decreasing diurnal net intake rates met their energetic needs with fewer flowers than those with constant net intake, and spent less time foraging. 5, It is concluded that P. longirostris do not satisfy the physiological as sumptions of the published model, and that in this way they are different f rom the territorial species on which the model has previously been tested.