Producer-scrounger roles and joining based on dominance in a free-living group of Mexican jays (Aphelocoma ultramarina)

摘要: Summary While foraging, animals often exploit group members to obtain food. One way describe this behaviour is with the producer-scrounger (PS) model, where scroungers use social interaction food discovered by producers. Mexican jays (Aphelocoma ultramarina) are a groupforaging species linear dominance hierarchy. We studied interactions in free-living foraging determine (1) if can be explained PS (2) these roles consistent and (3) or relatedness affects joining frequency. recorded board-flipping, eating, events during sets of feeding trials. show that were through many trials, but might have changed between trial sets. Relatedness frequency not correlated. Dominance influenced was more likely occur birds larger difference their rank. In contrast other studies, our results suggest effect mediated joiner preference. Scroungers preferentially joined lower rank high search activity. Producers qualities had fewer eating full access seeds, suggesting scrounging exacts cost on