Local management intensity and landscape forest cover affect bird community structure in shaded cocoa agroforests

Although agroforests are considered biodiversity-friendly systems, their capacity to support species diversity depends on local characteristics and the landscape context in which they are embedded. Therefore, we evaluated how management intensification and landscape forest cover affect bird community structure in 10 cocoa agroforests distributed across southern Bahia, Brazil. In each agroforest, we quantified management intensity based on four agricultural practices (weed control, fertilization, cocoa tree pruning, and number of cocoa trees) typically adopted by farmers. In addition, we estimated the amount of Atlantic Forest surrounding each agroforest within a 113-ha landscape. Using point counts, we sampled richness, abundance, and species composition for all birds, and separately for forest and non-forest species. In our study, we recorded 8,945 birds representing 139 species across 10 agroforests, including 73 forest species and 66 non-forest species. Our GLM models revealed that only management intensification negatively affected the richness and abundance of forest birds, while having the opposite effect on the abundance of non-forest birds. We also found that similarity in forest species composition decreased between agroforests with differing levels of management intensity. Moreover, differences in forest cover between agroforests reduced species composition similarity across all bird groups. Our findings revealed that less intensified agroforests may be more effective in maintaining bird diversity, mainly of forest species, possibly due to more favorable conditions and greater resource availability. Additionally, we detected that landscape forest cover influences species composition within agroforests. Thus, forest restoration may serve as a valuable strategy for bird conservation in these agricultural landscapes.