Terrestrial ecosystems of New Guinea | WWF
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Terrestrial ecosystems of New Guinea

River landscape, East Sepik, Papua New Guinea.

From cool forests to dusty savannas

Few places on Earth boast such a high concentration of different ecosystems and landscapes as New Guinea. But there you have it - savannas, swamps and mangroves, all have their place on the island and are associated to some degree with forests.

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New Guinea’s ecosystems have been molded by various factors including the island’s constantly growing mountains, and the impact of humans and invading species from the surrounding islands.

In addition to forests, savannas and rivers, smaller patches of littoral and swamp forests, as well as heathland, are also found in New Guinea.


Home to crocodiles, freshwater sharks, barramundi and hundreds of other fish species, the rivers of New Guinea rival terrestrial ecosystems in terms of complexity and diversity. They are also integral parts of forest ecology.
Some of the world’s great rivers flow through the island's forests, including the Asmat and Mamberano rivers in Indonesia's Papua Province, and the majestic Sepik River and lake country in Papua New Guinea (PNG).

Find out more about New Guinea's rivers


Stretching from the lowlands to altitudes beyond 3,000 m, New Guinea's forests show an enormous variety in species, aspect and dynamics depending on their location.

Find out about New Guinea's lowland and montane forests

Savannas and grasslands

Spread along the New Guinea’s southern coast, savannas are strangely reminiscent of the landscapes of northern Australia. Open savanna thrives in conditions that other ecosystems wouldn’t be able to withstand for very long. Here, there is no more than 2,600 mm of rainfall a year. In the dry season, it gets worse. Precipitation drops to less than 100 mm per month.

Find out about New Guinea's lowland and montane forests

Littoral forest

Distributed along the sandy beaches and adjacent plains of the southeast and southwest coasts, littoral forests include common canopy trees such as the Burmese rosewood (Pterocarpus indicus), also known as narra or angsana, and the paper bark tree or punk tree (Maleleuca species). In the southwest of the island, acacia palms (Acacia species) are common on the ground-layer and in lower tree layers.1

Swamp forests

The swamps are associated with some of the largest rivers, such as the Sepik, the Fly, the Strickland, the Mamberamo and the Purari. Sago trees, which are found close to the swamp forests, provide the staple starch for many people.2


Heath is found on poor soils in both highland and lowland New Guinea. In the lowlands, the vegetation grows on infertile soil of a sandy type. In the subalpine and alpine heaths, infertile soils support shrubs and meadows.3

1 Muller, K. 2004. The Biodiversity in New Guinea. Unpublished document.
2 Muller, K. 2004. The Biodiversity in New Guinea. Unpublished document.
3 Muller, K. 2004. The Biodiversity in New Guinea. Unpublished document.