Diversity and Community Pattern of Butterflies on Degraded Heath Forest in East Kalimantan

Abstract

Heath forest is one unique ecosystem in tropical regions. Many biodiversities and their ecological characteristic in this ecosystem are still unknown by science, including butterflies. Therefore, the study was conducted to determine butterfly richness and diversity indices in every site on natural secondary and degraded heath forests. A field study was conducted in two localities in East Kalimantan, i.e. Muara Badak and Sebulu areas. In every locality was located three sites for data gathering. The butterfly data were collected by capturing specimens using aerial insect nets and baited traps in August–September 2017. In general, the species richness in all sites lacked compared to the lowland forest habitat. During the study, only 200 individuals in 34 species were recorded in total. Calculation of Fisher’s alpha showed the diversity of butterflies in study sites in the range 2.28–16.35. Twenty-four main species spread in the study sites. Eight species showed strong fidelity for degraded heath forest habitats, moreover, Neptis hylas prefer fewer trees, and Mycalesis fuscum prefers denser trees. Meanwhile, there was no apparent taxonomical composition pattern, except family Nymphalidae with subfamilies Satyrinae and Limenitidinae, which showed superior in all sites. Other finding showed that the density of trees was affected to the geographic distribution of butterfly species; the denser trees appeared narrow distribution species, more prefer to Sundaland, and the sites with fewer trees appeared more comprehensive distribution species, more prefer to Oriental Region.