Relationship of Adult Butterfly (Lepidoptera: Rhopalocera) Diversity with Plant Species Diversity in Selected Areas of Mt. Magdiwata, San Francisco, Agusan Del Sur, Philippines

Abstract

Studies on butterfly diversity and their relationship to plant diversity are scarce and their importance are sometimes overlooked. Thus, a study in order to determine their relationship was conducted across three selected habitats (Agro-forest, Grassland and Secondary growth forest) of Mt. Magdiwata, San Francisco, Agusan del Sur using opportunistic sampling along 2-km transect lines. Fifty-two species of butterflies were collected (46 species in agro-forest, 37 species in the grassland, and 39 species in secondary dipterocarp) with Nymphalidae as the most species-rich family (58%). Ypthima sempera chaboras had the most number of individuals (N=81) accounting to 10.60% of the recorded butterflies. The overall diversity of butterflies was high (H’= 3.476). Local status showed that 64.74% of the species were very rare. In terms of plant species composition, a total of 1460 individuals from 33 species were recorded. Notes on plant diversity was also high in flowering plants (H’= 3.235) and adult nectar plants (H’= 3.099) possibly contributing to the high butterfly diversity in the area. Results of the correlation analysis showed that there was a strong, significant relationship between the butterfly diversity to nectar plant diversity (rs= .997 p = .047). Furthermore, linear regression analysis showed that the abundance of nectar plants explained 72.34% of the variation in the butterflies recorded in the area. Nectar plants is a highly important factor governing and supporting butterfly species population. Thus, the protection and conservation of herbaceous plants will equate to the conservation of not only butterfly species but of all the plant-dependent species in the area.