Redistribution of Sumatran orangutan in the Leuser ecosystem due to dispersal constraints and climate change

Abstract Sumatran orangutan (Pongo abelii) is one of the great apes that lives in Asia. The species’ population suffered a significant reduction due to altered habitat and climate shifting; thus, this species is critically endangered (CR) based on The International Union for Conservation of Nature (IUCN) red list. Nowadays, the vast majority of the species only occur in the Leuser ecosystem (LE). The population estimation of Sumatran orangutan towards ground-truthing methods still became a challenge to carry out conservation planning; therefore, the ecological niche modeling (ENM) will be a gan excellent alternative to evaluate this species’ population dynamics. Here we present the potential distribution changes of the Sumatran orangutan in the LE under mitigation and business as usual (BAU) scenarios of climate change. This study also conducted the effects of environmental constraint (i.e., deforestation and rivers) on the Sumatran orangutan’s future dispersal in LE. We collected the Sumatran orangutan occurrences data from the Global Biodiversity Information Facility (GBIF) and literature reviews of orangutan inventory in the Leuser ecosystem. The ENM and dispersal constraints have been conducted using ENMTML and MigClim R package script-codes, respectively. This study provides novel information regarding future orangutan distribution.