Cyprinus carpio was introduced into India during 1939 and 1957 for aquaculture purpose and it contributes more than 7.17% in total inland fish production. C. carpio was contributed maximum in the Yamuna river compared to Ganga river in landing scenario. Present investigation indicated that the growth rate was higher in the Yamuna river as compared to the Ganga river at Allahabad. The first two years growths were recorded 20.69 cm and 8.36 cm in the Yamuna river and 19.03 cm and 7.46 cm in the Ganga river, respectively. 0+ to 13+ age group fishes were recorded in the Yamuna while 0+ to 11+ age group fishes found in the Ganga. 0+ to 2+ age group fishes were highly exploited in the Yamuna (50.51%) in compared to the Ganga river (45.52%). The sex ratio of C. carpio var. communis was very close to expected sex ratio (1:1) in the Ganga and Yamuna rivers. At last it may be concluded that the C. carpio is a powerful invader in the Ganga and Yamuna rivers at Allahabad, India.

Dr. Ravindra Kumar Pathak mainly worked in the field of fish age, growth, population, reproduction, biodiversity, and studies on ecology changes and their impact on fisheries. He has published 16 research paper/articles in scientific journal of repute. He is also involved in fresh water parameter and soil analysis.