Intra-patch foraging strategy of the Ruby-throated Hummingbird (Archilochus colubris).

Abstract

The feeding habits of the ruby-throated hummingbird (Archilochus colubris) provide us with a good example of optimal foraging behavior. Hummingbirds have a high metabolic rate which forces them to feed frequently. When presented with both high and low energy sources, these birds will forage optimally to maximize their energy use. In order to determine how hummingbirds do this most efficiently, we set up simulated flower patches and recorded the duration of time of each visit and the number of flowers visited. Given a flower patch of randomly distributed low and high concentrations of nectar, a hummingbird will spend a significantly longer time at the patch if it finds a high concentration source during its visit. Contrary to our predictions, nothing significantly affected the total number of flowers sampled per visit. Two factors that may affect feeding behavior are temperature and site of foraging. Environmental factors such as low shelter from wind and the territorial interactions between other birds may decrease the time a hummingbird spends foraging.