Storm petrels trade movement speed for information gain

Animals travelling through air or water can benefit from surrounding flows. This is evident in procellariforms, oceanic birds capable of undertaking some of the longest journeys in the animal kingdom despite the need to periodically return to the nest. While airflow negotiation is well understood for larger species relying on dynamic soaring, less is known for the smallest species, which use flapping flight. Using GPS-tracking, we investigated wind use of the 28 g Mediterranean storm petrel (Hydrobates pelagicus melitensis). Birds actively searched for crosswind support at meso- (tens of kilometres) and macroscales (hundreds of kilometres). However, this reliance on crosswinds was associated with lower groundspeeds and a full compensation mechanism for drift during homing, implying an increased energy expenditure. Yet, crosswind support may facilitate navigation via a cognitive odour map and improve prey detection through olfaction, increasing the likelihood of intersecting odour plumes. These results indicate that storm petrels could face a trade-off between movement efficiency and information gain. Overall, our study offers new perspectives on the adaptations required to sustain aerial life in the marine realm and highlights the adaptability of seabirds in exploiting the windscape through strategic flow negotiation.