Where forests break, bats connect: bat–flower networks in a fragmented tropical dry forest

Abstract Tropical dry forests host essential mutualistic interactions between bats and plants, yet the intense fragmentation of these ecosystems threatens the persistence and structure of floral visitation networks. In Neotropical landscapes, these interactions exhibit high spatial and temporal variability driven by resource availability, plant turnover, and the mobility of bat pollinators. Despite substantial advances, community-level assessments that integrate β-diversity, modularity, and functional traits remain scarce, limiting our understanding of how bat–flower networks respond to habitat fragmentation. Here we show, using interaction-network and β-diversity analyses across eight fragments of Tropical Dry Forest in southwestern Colombia, that the bat–flower network is strongly modular and specialized, with modules primarily shaped by local plant composition. We found that species turnover, especially among plants, is the dominant component of β-diversity in interactions, whereas rewiring among co-occurring species is low and unrelated to geographic distance between fragments. We also demonstrate that four bat species form the cohesive core of the network and that morphological attributes such as body condition and face-skull ratio negatively predict their capacity to connect modules. These findings reveal how plant heterogeneity and bat mobility jointly determine network cohesion and functional redundancy in fragmented landscapes. Understanding these mechanisms is crucial for forecasting the resilience of bat–plant mutualisms under increasing anthropogenic pressures in tropical dry forests.