Cacay ( Caryodendron orinocense ) plantations filter bird functional traits and decrease diversity in the Colombian Orinoquía

Cacay (Caryodendron orinocense) is a native tree species increasingly cultivated in commercial plantations in the Colombian Orinoquía for its high-value nuts and oil, but the effects of this emerging tree crop on biodiversity remain poorly understood. We evaluated how cacay plantations influence bird taxonomic and functional diversity by comparing them with adjacent natural forests in the Colombian Orinoquía. Natural forests supported higher taxonomic and functional bird diversity than cacay plantations, where generalist bird species dominated and functional divergence and evenness were higher. Across both vegetation types, we recorded 117 bird species, including 3 Nearctic–Neotropical migrants detected primarily in natural forests. cacay plantations filtered out frugivores and nectarivores, contributing to ecological homogenization. Functional richness was higher in forests than in plantations, reflecting a broader functional space and the presence of species with extreme trait values, reinforcing the importance of natural forest for biodiversity conservation. RLQ ordination and fourth-corner analyses revealed that plantations were negatively associated with several sensitive guilds, including perch-foraging species, while favoring terrestrial and generalist bird species adapted to simplified landscapes. Landscape simplification reduced avian richness but maintained partially redundant functional assemblages in plantations. Although cacay plantations were dominated by generalist species occupying the remaining functional space, their functional resilience was constrained by the loss of key species and associated ecological functions. These findings underscore the importance of conserving remnant forests and promoting structural heterogeneity within and around plantations to enhance landscape connectivity and maintain avian functional diversity. This study provides the first empirical assessment of how cacay cultivation affects bird communities and offers guidance for balancing agricultural production with biodiversity conservation in the Orinoquía region.