Dams Pose Threat to Central Asia's Rare Fish and River Ecosystems

A recent study by the international environmental coalition Rivers Without Boundaries has highlighted key river basins in Central Asia that are crucial for biodiversity. However, many of these ecosystems are under significant threat due to the construction of dams and small hydroelectric power plants, which disrupt natural habitats and pose a danger to migratory fish species.

Using geographic information system (GIS) technology based on the ArcGIS platform, researchers found that only 12% of Central Asia’s rivers remain in their natural state, supporting rare and endemic fish species, The Caspian Post reports citing foreign media.

Another 7% of heavily altered freshwater areas are classified as critical habitats for endangered species, including the Amu Darya Shovelnose and Ili Marinka.

Endangered Fish and Disrupted Ecosystems

“We analyzed more than 50 endemic fish species across five major river basins in Central Asia,” said Eugene Simonov, lead researcher and international coordinator of Rivers Without Boundaries.

“Of these, 21 species are now classified as threatened on the International Union for Conservation of Nature (IUCN) Red List. Our study also examined the condition of tugai forests, rare floodplain plants, and key water-dependent species such as the Asian otter.”

The river network in Central Asia is increasingly fragmented due to dam construction, with the study documenting data on 650 existing and planned dams. As a result, migratory fish species are losing access to their spawning grounds. Some species, such as the Syr Darya false killer whale and Aral salmon, may have already disappeared.

Conservation Efforts and Solutions

To prevent further environmental damage, experts have developed a GIS-based tool to assess the impact of hydraulic structures on river ecosystems.

“This technology can help plan conservation strategies and protect valuable river systems,” said Eugene Egidarev, a GIS specialist at Rivers Without Boundaries.

Environmental scientists emphasize the urgent need to protect the remaining intact river sections, where rare fish species still survive. They also call for the preservation of floodplains and riparian ecosystems, which are essential for maintaining biodiversity.

As hydropower projects expand across Central Asia, balancing energy needs with environmental conservation remains a critical challenge. Experts warn that without stronger protection measures, the region risks losing more of its unique freshwater biodiversity, including species that have existed for millennia.