Covering as it does most of the major island groups within Southeast Asia, Indonesia is truly a "megadiverse" nation. In overall species richness the archipelago ranks as the third most biodiverse country in the world, behind only Brazil and Colombia. Indonesia can boast the most biodiverse coral reef communities on the planet, due both to its location within the extraordinarily species-rich Indian Ocean and its extensive area of coastline, the greatest of any country on Earth. As a nation of islands Indonesia's terrestrial wildlife contains an impressive variety of local endemics, as species confined to one part of the archipelago have diversified in isolation from other landmasses. The 19th Century British naturalist Alfred Russell Wallace identified the centre of what is now Indonesia as the point of contact between Asian and Australian faunas. The largest islands, New Guinea and Borneo (approximately half and two thirds of which, respectively, fall within the Republic of Indonesia), are individually among the richest in the world in terms of their biodiversity.
However, as with many of the world's most species-rich tropical regions, Indonesia's biodiversity is extremely heavily-threatened. The rainforests of Southeast Asia are subject to the highest rates of tropical deforestation in the world; it has been estimated that Borneo will lose most of its lowland rainforest with a few years. The growth of palm oil plantations to meet Kyoto targets and as a source for biofuels is accelerating rates of land clearance. The destruction of Borneo's peat swamp forests, combined with the practice of clearing land through burning, not only destroys critical wildlife habitat but has led to long-burning fires that now generate seasonal smogs over much of Southeast Asia and have made Indonesia the world's third largest emitter of greenhouse gases. Unsustainable fishing methods, including dynamiting, devastate coral reefs. The clearance of mangroves to farm shrimp increases runoff from soil erosion and agriculture into an already hard-hit marine ecosystem, while increasing the vulnerability of coastal communities to flooding and natural disasters. Almost entire island chain falls within two of the original biodiversity hotspots designated by Conservation International, a list of the world's most threatened high-diversity regions. Only Papua, the Indonesian portion of New Guinea, still has enough of its original forest cover to prevent its inclusion in a hotspot.
Indonesia's reptile fauna is characteristically large and diverse, but with such a great land area and relatively few herpetologists, much of this diversity is probably undescribed. The country's most celebrated reptile, the Komodo dragon (Varanus komodoensis), was only described in 1912. Indonesia's reptile fauna can boast a number of giants; the saltwater crocodile (Crocodylus porosus), the world's largest living reptile, ranges throughout the archipelago. The reticulated python (Python reticulatus) is almost equally widespread, and ranks as the world's longest snake.
|Tokay Gecko||Gekko gecko|
|Malaysian House Gecko||Hemidactylus frenatus|
|Water Monitor||Varanus salvator|
|Indonesian Spitting Cobra||Naja sputatrix|
Indonesia boasts a number of the world's most charismatic large mammals, many of them now critically endangered. The Sumatran orangutan (Pongo abelii), recently described as a separate species from populations on Borneo (the largest of which also occur in Indonesia), is an Indonesian endemic, as is the Sumatran subspecies of tiger. The Javan rhino may now be the rarest large mammal on Earth. Borneo is also home to populations of elephant and leopard. At the other end of the island chain, New Guinea sports several species of echidna, possum and tree kangaroo, remnants of a rainforest fauna lost from Australia as the continent dried. Indonesia is home to diverse primates, including tarsiers, gibbons and Old World monkeys, and to the colugo, a curious relative of the primates with well-developed gliding membranes that is sometimes referred to as the "flying lemur". Rodents are especially diverse; squirrels are numerous. In 2007, the world's largest rat was discovered during an expedition to the Foja Mountains in Papua.
|Spectral Tarsier||Tarsius spectrum|
|Buton Macaque||Macaca ochreata brunnescens|
With Papua New Guinea and Australia, Indonesia is one of only three countries in the world that can boast birds of paradise, famous for their extravagant plumage, often bright colours and bizarre courtship displays. The discovery of the 'lost' Berlesch's six-wired bird of paradise, a species only known from a century-old record, in the Foja Mountains made headlines in 2007. Hornbills are more widespread; nonetheless, Indonesia can boast endemic species of these animals as well. In total, over 1,500 species of birds are known from Indonesia.
|Brahminy Kite||Haliaster indus|
|Red-knobbed Hornbill||Rhyticeros cassidix|
|Sulawesi Hornbill||Penelopides exarhatus|