Landscape disturbance and change lead to impoverishment and homogenization of butterfly assemblages in Southern Mexico

Abstract

Abstract Mosaics on different land use types characterize current landscapes. This structural complexity is generally made up of areas of native vegetation, vegetation patches in different successional stages, agricultural areas and cattle ranching. In this paper we evaluated the influence of the structure and heterogeneity of fragmented landscapes on butterfly assemblages in a heavily fragmented area in Veracruz State, Mexico. From June to November 2021, ten landscapes were studied and characterized to estimate compositional and configurational heterogeneity, and the type and extent of the landscape elements present. 160 fixed transects were performed to gather measures of butterfly richness, abundance, diversity, dominance and habitat specificity. We recorded 91 species of three families, of which generalist species comprised more than 85% of the total number of species. Compositional heterogeneity and agro-pastoral systems negatively influenced species richness. Likewise, pastures and crops cover had a significant effect on species abundance. Our results showed that butterfly community in present tropical landscapes might be undergoing a process of biotic homogenization, since a vast majority of common and widespread species were dominant and despite an important amount of native vegetation still persisted in some of the study landscapes. Management of the agro-pastoral landscape should include the provision of environments (wooded pastures, remnant treefall areas) that promote the presence of functional habitat for a variety of butterflies, including those with specific habitat requirements.