The habitat suitability of Timor friarbird (Philemon inornatus) in Western Timor Island, Indonesia

Abstract

Abstract. Paga B, Pudyatmoko S, Wijayanti LR, Yuda P, Sulaksono N. 2021. The habitat suitability of Timor friarbird (Philemon inornatus) in Western Timor Island, Indonesia. Biodiversitas 23: 703-713. Timor friarbird is an endemic bird to Timor Island. The population of this bird has been declining due to land cover changes as a result of massive anthropogenic pressures. This study aimed to assess the suitability of Timor friarbird's habitat by using 12 ecogeographical variables. The sources of data included Sentinel 2A satellite imagery and remote sensing-based algorithms. The bird's presence was analyzed by using a combination of line transect with point count methods. Ecological Niche Factor Analysis (ENFA) model was applied to obtain habitat suitability value as well as coefficient of marginality (M) and specialization (S). These results showed that the Timor friarbird needs a habitat with a different value from the average of the entire habitat. High specialization value indicated that the species has a narrow ecological niche. Factors influencing habitat suitability included the distance from roads, the presence of mangroves, primary and secondary dryland forests, rivers, and low-density settlements. About 75% of the study area is classified as unsuitable habitat, and only 22% is suitable with range classes of suitability from marginal to optimal habitat. Areas with less anthropogenic pressure on the land cover will be preferred more by the bird. Improvement of unsuitable habitat and protection of suitable habitat, therefore, will be the most important strategy for Timor friarbird conservation.

Sustainable Management for Healthy and Productive Watersheds in Indonesia

“…RS technology allows for the scope of analysis to be wider spatially and temporally [200], while GIS has allowed for better spatial analyses with a combination of various watershed models. Several studies in Indonesia have used the integration of RS, GIS, and modeling for drought-prone area detection [201], habitat studies [202,203], landslide mapping [204], flood modeling [205], land use change [206], and land suitability change for specific species [207]. Modification models by integrating existing models or methods with various climate change scenarios will minimize the impacts of climate change.…”

Recent population size of Timor Friarbird and resources utilization at three landscapes in West Timor Island, Indonesia

“…This species plays an important role in forest ecosystems, agriculture, and other natural environments in the semi-arid region. Its population has decreased rapidly over the last decade, particularly in the western part of Timor Island [4,6,7]; the bird is not included in the list of protected bird species in the recent Indonesian Law (P.106 / MENLHK / SETJEN / KUM.1 / 12/2018). Previously Timor Friarbird was protected in PP No.…”

“…The studies reported that the density of the bird was very low (1 individu per two ha) [4,9]). Encounter rates in nature decreased by 82% from 2008-2011 [4] 2 continues to decline due to high anthropogenic pressure, such as habitat changes, hunting activities and wild trade of exotic and high-economic value birds [6,7]. In addition, climate fluctuations in tropical environments have intense dry seasons throughout the year, causing extreme productivity contrast in the dry and rainy seasons [11].…”

“…In the Western region of Timor Island, the largest area of suitable habitat for Timor Friarbird is located in Bipolo Landscape [7]. Studies of populations of this bird species in natural habitats on the island of Timor are minimally conducted by ornithologists, especially in the west Timor Island region.…”

“…Kupang bay from Kupang to Sulamau. The mountainous areas are in the Bipolo plateau, Fatuleu mountains, Fatumetan, and Fatubraun mountains in the Aramasi region[7].…”