Qualla: The Vanishing World of Lake Poso

The Vanishing World of Lake Poso: Introduction

Thu, 02 Apr 2026 00:00:00 GMT

Some of the rarest fish on Earth live in a lake most people have never heard of. Lake Poso sits in the highlands of Central Sulawesi, roughly 320 square kilometers of water filling a tectonic basin that formed roughly two million years ago. At 515 meters deep, it is Indonesia's third-deepest lake. That depth and that age have made it something remarkable: an evolutionary laboratory where species diverged in isolation for millennia, producing creatures that exist in this single body of water and nowhere else. Eleven fish species are endemic to Lake Poso. Several have not been seen alive since the 1980s.

The Vanishing World of Lake Poso: A Lake Between Two Towns

Thu, 02 Apr 2026 00:00:00 GMT

Pendolo sits at the southern end of Lake Poso, Tentena at the northern. Between them, the shoreline curves past smaller villages whose names rarely appear on international maps. At Tentena, the lake drains into the Poso River, which flows northeast through the lowlands to empty i...

The Vanishing World of Lake Poso: Eleven Species, One Address

Thu, 02 Apr 2026 00:00:00 GMT

The endemic fish of Lake Poso include the buntingi ricefish -- tiny, translucent creatures belonging to the genera Adrianichthys and Oryzias -- along with gobies of the genus Mugilogobius and the halfbeak Nomorhamphus celebensis. These are not charismatic megafauna. They are smal...

The Vanishing World of Lake Poso: The Invasion That Keeps Taking

Thu, 02 Apr 2026 00:00:00 GMT

The introduction of non-native fish species has devastated Lake Poso's endemic community. Mozambique tilapia and common carp were brought in to boost local fisheries, a pattern repeated across tropical lakes worldwide with predictably destructive results. The invasive species out...

The Vanishing World of Lake Poso: Creatures of the Shallows and the Forest

Thu, 02 Apr 2026 00:00:00 GMT

The lake's biological richness extends well beyond fish. A large assemblage of endemic Tylomelania freshwater snails inhabits the lake floor, their elongated spiral shells a hallmark of Sulawesi's ancient lakes. Eleven endemic Caridina shrimp species and several species of Parath...

The Vanishing World of Lake Poso: Deep Time, Running Out

Thu, 02 Apr 2026 00:00:00 GMT

Two million years is a long time for a lake to persist. Most lakes are geologically temporary, silting up or draining away within tens of thousands of years. Lake Poso's tectonic origin and great depth have given it staying power, and that persistence created the conditions for i...