Laguna La Amarga is a large hypersaline lake located in the semiarid central region of La Pampa province, Argentina. This lake holds a distinctive place in the regional landscape as part of a fluvial system that has become largely inactive due to human intervention over the past several decades. Historically, the river that once fed La Amarga carried sufficient freshwater to maintain low enough salinity levels to support fish populations. However, as that river system ceased to flow regularly, the lake gradually transformed into a hypersaline environment. Today, the water body is characterized by high salt concentrations, low phytoplankton productivity, and an ecosystem dominated by brine organisms rather than sport fish.