SARI BUMI KUSUMA

Report of Preliminary Survey of Bornean White-bearded Gibbon Hylobates albibarbis in Natural Forest Logging Conession of

PT Sari Bumi Kusuma-Nuak, Central Kalimantan.

by Achmad Yanuar and Chairul Saleh

Acknowledgments

This study was conducted as part of WWF Indonesia Programs in Arabela-Schwanner landscape with special target natural forest logging concessions within the landscape, especially in PTSari Bumi Kusuma Nuak, Central Kalimantan, one of member Alas Kusuma Group in order to protect endangered species of White-bearded Gibbon Hylobates albibarbis outside protected areas.

The study supported by Alas Kusuma Group which representative by Pak Ida Bagus Wiradnyana Putra as Head of Environment and Certification, who has given us the confidence to undertake survey of gibbon within logging concession areas of PT Sari Bumi Kusuma Nuak, Central Kalimantan. We would like also to thank you to management of PT Sari Bumi Kusuma Nuak for welcome us and provided several employers to participated in the survey, four-wheel vehicles for the survey activities as well as company guest house for the survey team to stay, especially Pak Adlin as PT Sari Bumi Kusuma Nuak Camp Managers and his staffs included Pak Yudhi Hendro (Assistant Manager of Planning ), Pak usilo Purnomo (Coordinator of TPTJ, Production and Certification),. Pak Jatmoko (Assistant of Research and Development and Environment), Pak Edi Sasangka (Assistant of Planning and Evaluation) and Pak Sasmoko (Assistant of Maintain and Forest Protection).

Summary

A prelimary survey of Bornean white-bearded gibbons Hylobates albibarbis population abundance outside protected area with special focus in natural forest logging concession have been conducted in IUPHHK-HA/Ijin Usaha Pemanfaatan Hasil Hutan Kayu-Hutan Alam PT. Sari Bumi Kusama-Nuak (PT Sari Bumi Kusuma Nuak). This survey was conducted from 20 to 29 March 2018 within three different locations of PT Sari Bumi Kusuma Nuak areas, namely at Camp 54, Camp 93 and Camp 53. Fixed-point count method employed to detected and plotted morning song bouts of gibbon groups for each listening post. Eighten listening posts established with six listening posts for each location and two observers noted and plotted of gibbon morning great calls at each listening post, so twelve field staffs from PT Sari Bumi Kusuma Nuak involved in this surveyed. Of listening posts location, gibbon groups density higher at Camp 53 (1.57 groups km^-2) than two other locations and lowest observed at Camp 54 (1.28 groups km^-2). We estimated density of this gibbon was 1.38 groups km^-2 in PT Sari Bumi Kusuma Nuak (2,028 groups, but need verification when there are not covered by forests in overall areas of PT Sari Bumi Kusuma Nuak, need calculation how many unforested areas, i.e ladang, local gardens in enclave area of PT Sari Bumi Kusuma concession areas). The forest in Camp 53 contiguous to the protection forest in the northern area, whilst the surrounding forests at Camp 54 is intacted to Bukit Baka Bukit Raya National Park in the eastern part of PT Sari Bumi Kusuma-Nuak concession areas. Meanwhile, the forests at Camp 93 are boundaried by another natural forest logging concession of PT Meranti Mustika in the southern part who has join operation with PT Sari Bumi Kusuma-Nuak. Due to the species of Bornean white-bearded gibbon has strictly protected by Indonesia law and listed as Endangered species by International Union for Conservation and Nature (IUCN), as a result need of the better management pratices to protect the population of this species within natural forests logging concession (outside protected areas).