The Biosphere was named Giam Siak Kecil – Bukit Batu since it is an area combined from around 72,255 ha of production forest managed by Sinar Mas Forestry, 84,967 ha of Giam Siak Wildlife Reserve and 21,500 ha of Bukit Batu Wildlife Reserve.
It is located in two Regencies, namely Bengkalis and Siak in the Province of Riau, Sumatera, Indonesia with altitudes ranging from 0 to 50 meters above sea level and is predominantly peat swamp forest. There are 80 villages located in and around the Giam Siak Kecil – Bukit Batu Biosphere Reserve with a total population of 237, 763 (2006 population cencus). Twelve of the villages are located in the buffer zone and the others are in the transition zone. The main community income comes from agriculture wit rubber, palm oil and rice paddy as the commodities. The reserve covers a gross area of 705,271 hectares spanning a wide range of land use types.
Regarding the biodiversity resources, Giam Siak Kecil –Bukit Batu, as part of the forests of Sumatera, hold one of the worlds’ greatest traesures of biodiversity, with 189 species, 113 genera, and 59 families of flora. From those 59 families, 29 species are listed under IUCN as follows: 8 endangered species, 2 vulnerable species, 1 near threatened species, 7 protected species, and 11 less concerned species. Furthermore, 3 orchid species are in CITES Appendix 1; these are Acryopsis cf.javanica, Cymbium sp., and Gramatophyllum speciosum. Ramin (Gonystylus bancanus) is also listed in CITES Appendix 2.
In term of fauna, 10 species are listed in CITES Appendix 1; Sun bear (Helarctos malayanus), Tapir (Tapirus indicus), Sumatran elephant (Elephas maximus), Sumatran tiger (Panthera tigris sumatrae), Sinyulong (Tomistoma schegelii), Hornbill (Buceros bicornis), etc.; and 26 species are listed in CITES Appendix 2.
The reserve also has a diversity of habitats having various elevation gradients and different soil types which include wetlands, peat swamp forests, and alluvial bench forests. The area is remote with limited human development and expansion. Thus access is difficult which kept it unspoiled and truly unique.