Diurnal butterfly diversity in a human-modified landscape of the subtropical montane forest of NW Argentina

Abstract

The change and intensification in land-use are currently among the main causes of species declines and local extinctions around the world. Therefore, forecasting changes in species diversity concerning habitat conditions may be crucial for conservation strategies. We explored diurnal lepidopteran diversity in a modified landscape of subtropical montane forests of Jujuy, NW Argentina. We considered that degradation of the natural forest habitat would likely impact resources crucial for butterflies, consequently altering both species richness and composition within these forests. We assessed and compared alpha diversity through Hill numbers diversity profiles and beta diversity through the beta-diversity partitioning. Additionally, we employed a permutational multivariate analysis of variance, and rank-abundance curves of butterfly species across different habitat types. Our results suggest that land-use changes diminish the number of forest-dependent species and increase species more tolerant to modified habitats and open areas. While alpha diversity did not decrease as land use changed, beta diversity showed significant changes in butterfly species composition, with a worrying reduction of forest-related species in altered habitats. Species composition became increasingly dominated by open area butterfly species resulting in biota homogenization, with potential consequences for ecosystem functioning and services in these forests. Further research on the mechanisms underlying the effects of human-induced habitat changes on forest butterfly diversity could help clarify which mitigation strategies are most likely to be successful for the conservation of butterflies of the subtropical montane forests.