Learning ability of the Ruby-throated Hummingbird (Archilochus colubris) in response to variable placement and sucrose content of feeders

Abstract

Compared to other species of birds, the Ruby-throated Hummingbird (Archilochus colubris) must forage more frequently to maintain their high metabolic rates. They must be able to quickly determine profitable food sources and adapt to changing conditions. We studied the memory and learning of A. colubris by observing their behavior in a natural setting when confronted with new nutrient-rich food sources with varied placement and sucrose content. Our data suggest that A. colubris commit a food source's position and viability to memory between 20 minutes and one hour of it being introduced. Additionally, A. colubris are significantly more likely to revisit a feeder where a sucrose colution had previously been present, suggesting a learned response. As there was some evidence A. colubris may be able to differentiate between feeders due to olfactory cues, further investigation is needed to determine if this is the case in a natural setting.