Fragmentación del paisaje como potencial impulsor de cambio morfológico y funcional en la comunidad de aves del bosque Subandino de los Andes Orientales

Abstract

Habitat fragmentation represents a critical threat to biodiversity, particularly in Neotropical ecosystems like the Sub-Andean forests of Colombia, where human activities have fragmented once-continuous habitats into isolated patches. This study analyzes how fragmentation potentially influences avian morphological and functional traits at both community and intraspecific levels across a gradient of fragmentation in a single landscape. Using transect surveys, mist-netting, and morphological measurements, we compared species richness, functional diversity indices (functional richness, evenness, dispersion and divergence), and intraspecific trait variation in the Yellow-bellied Seedeater (Sporophila nigricollis). We found two major patterns, both at the species and community levels. The first was a shift toward shorter legs and longer tails in fragmented landscapes in S. nigricollis. For the entire community, we found a shift toward birds with greater dispersal ability in fragmented landscapes. Functional diversity indices showed no differentiation. The second, was a slightly expanded variability in trait space in fragmented habitats, both at the intra-species and community level. These findings suggest that fragmentation can indeed be a vector for morphological and functional variation in this Andean community of birds, and within a single species. Likely these changes are happening in unison with a myriad of other factors interplaying the complex ecological relationships present. More extensive studies in other communities and landscapes could further shed light on the patterns, effects and specific drivers. Our study emphasizes the need to integrate both community-wide and species-specific trait analyses to guide conservation strategies, advocating for habitat connectivity to sustain ecological processes in human-modified landscapes.