Salween River ecosystem

• Category: Inland Aquatic Biomes.
• Geographic Location: Southeast Asia.

Summary: Flowing through rugged, mountainous terrain, the Salween is relatively unspoiled but in jeopardy from mining, logging, and dam construction.

The Salween River of Burma (Myanmar) runs through a rugged, mountainous, north-south series of narrow valleys and gorges; it is approximately 1,500 miles (2,400 kilometers) in length. Glaciers in the eastern highlands of the Tibetan Plateau form the sources of the Salween River. Its path takes it southward through Yunnan Province in China, then along parts of the Myanmar–Thailand border, and finally into the Andaman Sea.

The Salween begins approximately 13,100 feet (4,000 meters) above sea level. Only one southeast Asian river, the Mekong, is longer than the Salween River. Throughout its history, the Salween has been a free-flowing river, but recent pushes, especially in the twenty-first century, from various governments and commercial interests to add multiple dams along the Salween could change the river and its ecosystem quickly. Dams remain one of the greatest threats to the wetlands and the river.

This great river is known by many names as it courses through China, Thailand, and Myanmar; the Chinese call it the Nujiang, or angry river, perhaps reflecting its rapid flow as it streams through sheer canyons in its upstream segments. Fishing is a primary source of income and food for many human inhabitants of the 120,000-square-mile (320,000-square-kilometer) Salween watershed.

From its beginning in the Tanggula Mountains on the Tibetan Plateau through its terminus at the Andaman Sea in Myanmar, the river undergoes dramatic changes. Portions of it are known as the Grand Canyon of the East, while other segments water woodland- and agricultural-dominated plateaus and valleys. The Salween is recognized as being in relatively pristine condition, with much of its biome intact.

Recent plans to dam the river have met with fierce resistance in some quarters, especially among Indigenous peoples, as such measures would dramatically change both the nature of the river and its biota, endangering many species of flora and fauna that rely upon the Salween’s free-flowing waters, and jeopardizing the livelihood of many humans. Fish spawning grounds and migratory pathways are of particular concern.

Biodiversity

Among a diverse flora, montane evergreen forests are spread across many ridges upstream, while mangroves are found near the Salween Estuary.

The Salween River area has been known to support about 362 species of fish, 7,000 species of plants, and up to 80 different types of endangered species in all. Minnows are by far the most prevalent fish found here. Some endemic (found nowhere else) fish species are Hampala salweenensis and Hypsibarbus salweenensis; about a quarter of the species inhabiting the biome are endemic.

Larger fauna in the Salween River biome include Siamese crocodiles, Asian small-clawed otters, and the fishing cat. Turtles are an important component of the ecosystem and a food source for many. Among the dozen different turtle species found in the Salween River are the Asian leaf turtle (Cyclemys dentata), giant Asian pond turtle (Heosemys grandis), and big-headed turtle (Platysternon megacephalum).

Threats

Mining, logging, and other disruptive human activities can undermine the high-relief landforms along the Salween River, adding to erosion and exacerbating the damage done by frequent landslides during the rainy season. Flooding, increased siltation and turbidity in the river, and fragmentation of habitats are the typical outcomes. Climate change impacts along the Salween River range from altered glacial melt regimes at the source, to heavier monsoon precipitation and wind across the main segments, to sea-level rise at the mouth. Additionally, some research suggests that dam construction is a net additive to global warming—apart from the destruction of forested areas it necessitates—by creating stagnant reservoirs conducive to algal blooms and rotting plants that release quantities of greenhouse gases. Political instability in Myanmar, especially after the February 2021 coup, has severely complicated conservation and cross-border cooperation in the basin. After Myanmar’s military seized power, cross-border cooperation on the river was disrupted.

As the government largely failed to make concerted conservation efforts, the Salween Peace Park stands out as a major community-led conservation initiative. Established in 2018 in Karen State in Myanmar, it protects thousands of square kilometers of forests, rivers, and wildlife along the Salween River. Managed by Indigenous communities, the park uses traditional ecological knowledge to conserve ecosystems that support the river and downstream areas.

Bibliography

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Zhou, W., and X. Li. “Fish diversity and selection of taxa for conservation in the Salween and Irrawaddy Rivers, Southeast Asia.” Scientific Reports, vol. 14, 2024, www.nature.com/articles/s41598-024-51205-5.pdf. Accessed 12 Mar. 2026.