Evidence for olfactory learning in procellariiform seabird chicks

Burrow nesting procellariiform seabirds use olfactory cues for both foraging and nest recognition. As chicks, burrow nesters develop in the dark, but are exposed to both prey‐related and individual‐specific scents through contact with their parents. This exposure suggests that chicks may have the opportunity to learn odours while still in the nest. In this study, we examined whether exposure to odourants during development might influence olfactory search behaviour expressed later in life. To test this idea, we exposed eggs of thin‐billed prions Pachyptila belcheri to a rosy‐scented novel odour (phenyl ethyl alcohol, PEA) or a control (water) just before hatching; chicks were then tested with these odours in a simple wind tunnel. Prior to fledging, subjects who had received pre‐exposure to PEA displayed head sweeps nearly twice as frequently as control birds did when presented with PEA. This study demonstrates that under natural rearing conditions, procellariiforms learn odour characteristics of their rearing environment in the nest.