ANALYSIS OF THE RELEASE READINESS OF BORNEAN ORANGUTAN (PONGO PYGMAEUS LINNAEUS 1760) AT BORA REHABILITATION CENTER IN BERAU, EAST KALIMANTAN

• Main Author: Nabila Aini, Dinda
• Format: Final Project
• Language: Indonesia
• Subjects: Ilmu hayati ; Biologi
• Online Access: https://digilib.itb.ac.id/gdl/view/74669
• Institution: Institut Teknologi Bandung

The population of Bornean orangutan (Pongo pygmaeus) is currently experiencing a drastic decline due to habitat fragmentation, hunting and illegal wildlife trade. Rehabilitation program is considered very important as one of the efforts to maintain the population of these animals in their natural habitat. However, the success rate of the rehabilitation programs is still hampered by the lack of an evaluation process carried out to determine the readiness of rehabilitant orangutans to be released. Therefore, this study aims to analyze individual orangutan release readiness based on several assessment indicators, including daily activity, natural food consumption, home range, arboreal activity, response to potential predators, and abnormal behavior tendencies. Behavioral observations were carried out using the focal animal sampling method - instantaneous sampling at 5 minutes intervals during Forest School (09.00 - 15.00 WITA). Observation of home range is carried out through spatial data recorded by a GPS receiver and then calculated using Minimum Bounding Geometry in QGIS Desktop 3.28.1. Observations were made of four individual orangutan release candidates named Bonti, Jojo, Mary and Popi at the BORA Rehabilitation Center. Bonti and Mary have the highest proportion of eating activity. The four individuals are mostly arboreal, but the proportion of Popi’s activity on the ground is still high. Bonti, Mary and Jojo commonly did their activities at a height above 6 meters. These four individuals traveled at a very high distance, but they have a relatively low home range compared to wild and ex-rehabilitant orangutans. Popi was still finding it difficult to identify predators and find natural foods on her own. Abnormal behavior was found in the four individuals with different severity. Based on the final scores of the four individuals, the orangutans whose status was ready to be released were Bonti, Jojo and Mary, while Popi was considered not ready and still had to undergo a further rehabilitation process.