Assessing potential habitat suitability of vulnerable endemic species: a case study of Diospyros celebica Bakh and Rhyticeros cassidix

Abstract

Diospyros celebica Bakh and Rhyticeros cassidix are known to be associated in several locations in Sulawesi. Both of these species are endemic to Indonesia that live throughout the island of Sulawesi. Species Distribution Modeling using Maximum Entropy (MaxEnt) is considered an alternative way to understand the potential area suitable for a species. Model predictions from MaxEnt for all species have an AUC value of 0.887 and 0.837. Suitable habitat for D. celebica Bakh in Central Sulawesi (Morowali Utara, and The southern coast of Banggai) and South Sulawesi (Luwu Timur, Luwu Utara, Toraja Utara, Barru, Pangkep, Maros, Sidrap, Wajo, Sidenreng Rappang, and Gowa). However, the suitable habitat for D. celebica Bakh and R. cassidix in the association is much smaller. Environmental variables that are considered important that influence the occurrence of D. celebica Bakh are Soil Types, especially soil types Dystric Fluvisols, Eutric Fluvisols, Or-thic Luvisols, Orthic Acrisols, Eutric Cambisols, rainfall, and bio13. While R. cassidix is affected by distance from roads, distance from settlements, and distance from rivers, based on actual data points and habitat predictions. Most of the suitable habitat for D. celebica Bakh and R. cassidix is estimated to be outside the conservation area, but the suitable habitat is estimated in 8 functional status conservation areas. These results can be used by the Government of the Republic of Indonesia, and the Ministry of Environment and Forestry for determination.

Assessing Potential Distributions of Bird Endemic Species: Case Studies of Macrocephalon maleo and Rhyticeros cassidix and Their Threats

“…The potential distribution was modeled using the MaxEnt software (Version 3.4.4) for both the endemic bird species and the threats using a machinelearning technique called maximum entropy (MaxEnt) [22]. Maximum entropy is one of the SDMs that is widely used for species-distribution analysis; for example, it is used to assess distributions or associations among species [36]. In addition, MaxEnt was used to analyze the effects of the land-use change [37], assess the species distributions due to the effects of climate change [38][39][40], assess the disaster risk [41][42][43], and assess the invasive species [44].…”