Modeling the predicted suitable habitat distribution of Javan hawk-eagle Nisaetus bartelsi in the Java Island, Indonesia

Abstract

Nursamsi I, Partasasmita R, Cundaningsih N, Ramadhani HS. 2018. Modeling the predicted suitable habitat distribution ofJavan hawk-eagle Nisaetus bartelsi in the Java Island, Indonesia. Biodiversitas 19: 1539-1551. Javan hawk-eagle (Nisaetus bartelsi) isan endemic raptor of Java Island. The conservation status of Javan hawk-eagle (JHE) according to IUCN is endangered (EN) andincluded in CITES Appendix II list, and this species is also protected by the Indonesian government law based on act no. 5, year 1990.The position of Javan hawk-eagle as a top predator is now very threatened by habitat fragmentation, wildlife trade, and the decliningquality of its habitat. The primary purpose of this study was to give preliminary information about the distribution of predicted suitablehabitat for JHE as a means of finding potential releasing sites, as an evaluation for habitat protection, and even as an option for thedevelopment of new JHE protected areas. However, mapping the spatial distribution of potential habitat for JHE using terrestrial surveyis problematic because it requires enormous time, fund, and human resources. The most possible approach is by using Ecological NicheModeling (ENM)/species distribution modeling (SDM). In this study, modeling exercise was conducted by using a maximum entropymethod as an adaptation from Maxent software ver. 3.4.1, with the utilization of JHE-nest coordinate data and 16 environmentalvariables datasets as the main input. The predicted suitable habitat distribution map has shown a good match with historical and presentrecords of JHE and has fairly succeeded in capturing a wide range of habitat patches from tiny spots to quite large suitable habitat.Modeling results also showed that altitude, annual mean temperature, and two types of land cover (closed shrub, and forest area) areconsidered to be most important variables affecting the distribution of potential habitat for JHE. Moreover, about 17.77% (23,209 km2)area of Java Island has been projected to be suitable for Havan Hawk-Eagle's habitat, which mostly spread in mountainous areas whilealso appear in several lowland areas. This study suggests the importance of topographic, climatic, and land cover as pivotal predictors indetermining the suitability of habitat for JHE. This study also shows that the modeling results have a good match with the historicalrecords of JHE across the island, which suggests the overall accuracy of the model.

Evaluation of Climate Change Impacts on the Potential Distribution of Styrax sumatrana in North Sumatra, Indonesia

“…Among all of the regions in Indonesia, North Sumatra is one of the regions with a massive forest area that has been threatened by climate and land-use change [5]. North Sumatra has experienced large-scale development in the last three decades, and industrialization Species distribution modelling has also been applied in Indonesia, for example, to estimate bird distribution [24] and to predict the endangered tree species distribution in Borneo [25]. Moreover, alien invasive species distribution has been modelled in a national park using the MaxEnt and GLM approaches [24,26].…”

Pemodelan Spasial Kesesuaian Habitat Elang Jawa (Nisaetus bartelsi) di Taman Nasional Bromo Tengger Semeru (Spatial Modeling of Javan Hawk-Eagle (Nisaetus bartelsi) Habitat Suitability in Bromo Tengger Semeru National Park)

“…Pada tahun 2002, populasi elang Jawa yang tersisa di seluruh Pulau Jawa diprediksi hanya sekitar 325 pasang (Nurfatimah et al 2016). Penyebab turunnya populasi elang Jawa adalah tingginya kerusakan hutan di Pulau Jawa sehingga dapat menganggu habitat satwa yang ada di dalamnya (Nursamsi et al 2018). Selain itu faktor biologis juga sangat berpengaruh terhadap populasi elang Jawa, karena mereka hanya kawin setiap dua tahun sekali untuk menghasilkan satu butir telur saja (Azmi et al 2016).…”

“…Standar ini menekankan pada jumlah relatif nilai atribut terhadap nilai lain, jika nilai atribut memiliki rentang 0 -300 maka diasumsikan terbentuk 3 kelas kategori kesesuaian habitat (Khan 2016 Hasil perhitungan akurasi yang sudah termasuk dalam program MaxEnt direpresentasikan dengan nilai AUC (Area Under the Receiver Operating Characteristics). Nilai AUC digunakan untuk menguji akurasi model yang dibuat oleh MaxEnt (Nursamsi et al 2018). Apabila nilau AUC lebih tinggi dari nilai standar devisiasi maka model tersebut memiliki akurasi yang sangat tinggi.…”

“…Kondisi kawasan dengan kemiringan yang curam pada TNBT merupakan kawasan gunung berapi, semak, savanna dan tanah kosong, sehinnga kawasan tersebut tidak mendukung habitat bagi elang Jawa. Hasil nilai variable penting kemudian diuji lanjut dengan Area Under the Receiver Operating Characteristic (ROC) Curve (AUC), uji ini dilakukan guna mengetahui variabel dan pengaruhnya bagi model kesesuaian habitat (Nursamsi et al 2018) elang Jawa di TNBTS (Gambar 4). Gambar 4.…”

Avian diversity in geothermal power plant areas: Case studies in Kamojang, Darajat, and Gunung Salak, West Java, Indonesia

“…Within Accipitridae family, there were 5 species in which one species has EN conservation status, which is Nisaetus bartelsi (Javan hawk-eagle). This N. bartelsi is an endemic raptor of Java Island which is currently severely threatened by both wildlife trade and habitat loss (Nursamsi et al 2018).…”