· The Crossroads of Fire and Water
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
· Looking Ahead

Global 200 Snapshot

This ecoregion contains a diversity of freshwater habitats, including hill streams, lowland floodplains, and peat swamps. The fish and decapod crustaceans of this ecoregion are remarkably rich and differentiated, with endemic species found in many individual river basins. Many species live only on specific islands.  

The Crossroads of Fire and Water

Far beneath our feet lie the huge, interlocking tectonic plates that make up the crust of the Earth. The Sundaland Rivers and Swamps flow in a part of the world where several of these plates meet and constantly jostle each other. All this movement often sparks earthquakes and volcanic eruptions.

Special Features

The different islands in the Sundaland region have high mountains, dense forests, and wide valleys. Among all these places flow many rivers and streams. Rivers such as the Kapuas, Pawan, and Pesaguan start in the hills of central Borneo and run southwest, creating swamps and deltas along the sea. The coastal peat swamps and swamp forests in Malaysia, Sumatra, and Borneo are home to many unusual species that are found nowhere else. These special habitats have still waters and lots of vegetation. And on northeastern Sumatra, the Asahan River carries fertile soil across wide plains before spilling into the Strait of Mallaca.

Not very many people have walked from Asia to Australia, at least not since about 40,000 years ago. At that time, much of the world's water was trapped in glaciers. A vast dry area known as Sundaland connected the continents and served as a footpath for humans migrating south. When the Earth's temperature later rose and the glaciers melted, large parts of the region were submerged under the ocean.

Wild Side

The floodplains, foothills, and peat swamps of this ecoregion are rich in fish species. These habitats support many endemic fish that have very small distributions (some possibly only a few square miles). For example, about 100 endemic fish live in peat-swamp forests in this region. There are more than 270 known species of fish on Sumatra alone, 30 of which are endemic. And of the nearly 400 known species of fish that call Borneo home, 149 are endemic. Endemic freshwater fish include several shark catfish of the Pangasius genus, several bettas, four species of hillstream loaches, tapah, and the endangered Asian arowana.

Cause for Concern

Deforestation, conversion of land to agriculture, overfishing, the introduction of exotics, the aquaculture industry, and mining pollution threaten these habitats and their native species. Proposed hydropower dams on high-gradient streams would jeopardize natural flows and the movements of resident species.

Looking Ahead

Check back soon for more about the conservation of this ecoregion.