PRAYAGRAJ, April 19 -- The aquatic ecosystem at the Sangam in Prayagraj is undergoing a notable transformation with a new research indicating significant changes in fish species composition in the Ganga. A decade-long study by the Central Inland Fisheries Research Institute (CIFRI), Prayagraj, of Indian Council of Agricultural Research (ICAR) has found that the population of Indian Major Carp (IMC) species has doubled over the past 10 years. These include key indigenous species such as rohu, catla, mrigal and kalbasu. At the same time, the population of exotic carp species, including common carp and tilapia, has declined sharply. Scientists say the trend reflects improving water quality in the Ganga. According to CIFRI director Balasaheb Chavan, IMC species thrive in clean water, while exotic carp are more tolerant of pollution. The rising share of native carp is therefore seen as an indicator of better river health, likely supported by ongoing conservation efforts. Research conducted under the National Mission for Clean Ganga since 2017 across various ghats of the Sangam shows a clear shift in species distribution. Data reveals that until 2016, IMC species constituted only 12% of the total fish catch, while exotic carp made up around 40%, and other species accounted for 48%. Recent figures show IMC species rising to over 24%, while exotic carp have dropped to around 20%, with the remaining 56% comprising other fish varieties. The Ganga supports nearly 230 fish species, forming a crucial ecological and economic lifeline. Experts note that Indian Major Carps play an important role in maintaining river cleanliness as they feed on organic debris such as plant matter. Each fish can produce between 2.5 to 3 lakh offspring, potentially boosting populations of species that depend on them, including the endangered Ganges river dolphin. The shift also has economic implications. IMC species such as rohu, catla, mrigal, and kalbasu are in high demand in local markets like Daraganj and Sadiyapur, owing to their nutritional value and taste. Their increasing availability is expected to improve the livelihoods of local fishing communities, shared CIFRI scientist Dharmanath Jha. However, many scientists caution that the trend is not without risks. The dominance of IMC species could disturb the ecological balance by increasing competition for resources and threatening smaller, native fish species that contribute to aquatic biodiversity, they warn. Scientists warn if IMC populations grow unchecked, they may begin to prey on or outcompete other species, potentially reducing biodiversity in the long run. This emerging imbalance poses a new challenge for conservation efforts. As part of ongoing restoration initiatives, around 9 lakh IMC fingerlings have been released into the Ganga between 2024 and 2026. While these efforts have contributed to the revival of native species, some experts stress the need for continuous monitoring to ensure that ecological gains do not lead to unintended consequences....