The role of sterile apices of Puya chilensis (Bromeliaceae) on the nectar-feeding behavior of passeriform birds in central Chile

The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis (Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.