The National Green Tribunal (NGT) has issued directions to the State governments of Uttarakhand, Himachal Pradesh, Delhi, Haryana and Uttar Pradesh, along with other authorities, to take a slew of measures to arrest the falling population of native fish in the Yamuna river and control the spread of exotic species.
The tribunal also directed authorities to take strict penal action against those responsible for the illegal introduction of exotic fish species into the river.
The order followed a suo motu case registered on the basis of a news report highlighting the decline of native fish and the rise of exotic species. The 2024 report cited a study by the Central Inland Fisheries Research Institute (CIFRI), Prayagraj, which stated that fish in the Yamuna were being affected by climate change with Indian species declining while foreign species increasing.
The Principal Bench of the NGT, comprising Chairperson Prakash Shrivastava and Expert Member A. Senthil Vel, also directed authorities to control pollution in the river, identified as the main cause for the reduction in fish populations.
“The Central Pollution Control Board, National Mission for Clean Ganga, and Delhi Jal Board are directed to ensure strict enforcement of effluent standards and compliance with norms by Urban Local Bodies discharging treated or untreated sewage and dumping solid waste into the Yamuna, as well as by industries releasing treated or untreated effluents,” stated the NGT order dated January 29.
The tribunal also directed the acceleration of installation and operationalisation of sewage treatment plants in areas along the Yamuna to ensure treated water meets standards fit for aquatic life.
The Ministry of Environment, Forest and Climate Change, Central Water Commission and State Irrigation Departments were asked to maintain minimum flow levels to support breeding and migration of native fish. Authorities were also directed to regulate or prohibit sand mining that disturbs spawning beds and to remove obstructions or construct fish ladders at barrages such as Wazirabad, Okhla and Hathnikund to aid the migration of species like Mahasheer.
The NGT called for a ban on farming highly invasive species such as Thai Mangur (Clarias gariepinus) and promotion of native aquaculture through incentives for species including Catla, Rohu, Mrigal, Chital, Mahasheer and Eel.
Published – February 02, 2026 01:30 am IST


