Lepidoptera as a tool for the assessment of human disturbance impacting ecological and taxonomic diversity in the Choke Mountains, Ethiopia

Abstract

In tropical countries, frequent anthropogenic disturbances are primary drivers of the reduction in community diversity and local extinction of many insect taxa, including Lepidoptera. We assessed the impact of anthropogenic disturbances on lepidopteran assemblages across five different land use types (Fragmented Forest, Crop Fields, Pasture Land, Rural Settlements and undisturbed Natural Forest) in the Choke Mountains, Ethiopia. Lepidoptera were sampled using 20 W UV LED lights in 19 sites for 12 consecutive months. A total of 4 559 specimens representing 14 families and 339 species were sampled. The highest diversity was obtained from the Natural Forest, followed by the Fragmented Forest, Rural Settlements, Pasture Land and Crop Fields. The monthly trends of the diversity estimates showed strong differences among the five land use types, with months when the highest Hill–Shannon and Hill–Simpson values were observed not in the Natural Forest, but in the Rural Settlements and Fragmented Forest. The highest dominance values were observed in the Crop Fields and Pasture Land, with dominant species percentages of about 10%. The multivariate results clearly highlight the separation of the Natural Forest sites from all other sites and, in general, great consistency within each land use. A high positive linear relationship between the number of vascular plants and sampled Lepidoptera species was observed. The results of this study will be useful for guiding conservation management priorities to prevent irreversible biodiversity loss and maintain ecosystem provisioning services that are essential for the sustainable development of rural communities.