Network analysis highlights the complementary roles of active and passive restoration for birds in a restored landscape mosaic

Abstract

Birds are essential in connecting conserved and restored habitats in anthropogenic landscapes, acting as ‘mobile links’ that en hance habitat connectivity. They contribute to key ecological functions that support habitat recovery. Despite their sensitivity to habitat changes, bird assemblages in restored landscapes show varied responses due to factors like the restoration technique employed. This study uses the species–habitat network approach to assess how different restoration techniques and bird functional traits influence bird habitat use and connectivity in the Atlantic Forest. We adapted network metrics—among- module connectivity and within- module degree (c- and z- scores, respectively)—to quantify how habitat types contribute to landscape connectivity and to assess how bird functional traits explain patterns of occupancy across restored fragments. We show that actively restored habitats tend to have more exclusive bird species compared to conserved forests, whereas naturally regenerated forests support a broader range of shared bird species. While active restoration often promotes species with specific habitat needs, it may have a more limited role in landscape connectivity, compared to natural regeneration, which better integrates habitat types. These findings suggest that combining active and passive restoration strategies can maximise landscape connectivity, with active restoration providing habitat for species with particular requirements and passive restoration enhancing broader ecosystem recovery through bird occupation. Additionally, our findings indicate that bird functional traits have low explanatory power for patterns of bird habitat use in restored landscapes, emphasising the value of a more detailed network approach that includes species- specific interactions. Still, the species–habitat network approach revealed key species that help connect different habitat types, highlighting the role of bird species in landscape cohesion. Future research should explore finer network resolutions and larger spatial scales to better capture species movement and habitat dynamics within restoration gradients.