Population and conservation status reassessment of Etlingera balikpapanensis A.D. Poulsen, an endemic ginger in East Kalimantan

Abstract

Abstract The Balikpapan ginger (Etlingera balikpapanensis A.D. Poulsen) is a ginger species endemic to East Kalimantan Province, Indonesia. Known only from two locations near Balikpapan City, the species is threatened by forest encroachment and forest fires. To provide the most current distribution and population size as well as to reassess its extinction risk based on IUCN Red List Category and Criteria of the species, we therefore carried out a population survey in the intact forest of Balikpapan Botanical Garden and the adjacent areas of Sungai Wain Protected Forest. Using focused or intuitive-controlled survey method, we located 14 clumps of E. balikpapanensis with a total of 171 individuals. Based on the occurrence points collected during the survey and additional records from peer-reviewed papers, the calculated extent of occurrence (EOO) and area of occupancy (AOO) of the species were 1,292.265 km2 and 20 km2, respectively. Therefore, we considered E. balikpapanensis as Endangered (EN) under criteria B1+2ab(iii), C2a(i). Under this category, E. balikpapanensis was considered to be facing a very high risk of extinction in the wild.