River-linking project in India could spread invasive species to sensitive ecosystems

New Ecological Risks

India's massive National River-Linking Project could act as an ecological highway for unwanted alien species to enter sensitive aquatic habitats. Researchers from a Bengaluru-based institution evaluated the project and found that connecting isolated river basins allows invasive plants and animals to spread beyond their current boundaries.

Vulnerable Basins

The study shows that peninsular and northeastern river zones face a higher risk of biological invasions than central and northern regions. For instance, the Lower Ganga area currently holds between 13 and 15 invasive species and risks becoming a major supplier of these unwanted organisms to the Mahanadi basin, which houses 69 threatened species. Experts warn that native fish populations lack immunity to foreign pathogens that might travel through these new water channels, potentially pushing rare local species toward extinction.

Policy Concerns

Environmental experts point out that moving water from wet regions to dry zones ignores how natural ecosystems function. Besides biological threats, altering river flows can lower water levels downstream, disrupt fish migration, and damage sediment transport. Researchers urge authorities to create dedicated national policies to manage and control invasive species before infrastructure work advances further.

Context

Large-scale infrastructure projects often disrupt natural boundaries that have kept distinct regional species isolated for millennia. When water systems are artificially merged, the natural balance of local habitats is frequently upended in ways that are difficult to reverse.