Box 1: Biodiversity in the forests where orangutans occur
Sumatran orangutans live in tropical rainforests, which are among the most biodiversity rich ecosystems on earth, boasting an unmatched richness in flora and fauna when compared to other terrestrial ecosystems (Gaston 2009).
Sumatra ranks particularly high and the entire geograph- ic range of the Sumatran orangutan sits within one of the world’s top three so-called biodiversity hotspots. These are the richest and most threatened reservoirs of plant and animal life on Earth. This particular hotspot is called
Sundaland and includes the islands of Sumatra, Borneo and Java, and Peninsular Malaysia (Myers et al. 2000).
Forests that support Sumatran orangutans also harbour high numbers of other animal and plant species, including some of the most emblematic megafauna species in the world, the Suma- tran tiger (Panthera tigris sumatrae), Sumatran elephant (Elephas maximus sumatranus) and Sumatran rhinoceros (Dicerorhinus su- matrensis) (Map 7).
All are now on the brink of extinction (IUCN 2010).