Hyderabad: Telangana's fish diversity, the highest among states in the Godavari River basin, is under significant threat due to sand mining, pollution, deforestation, and unscientific fishing practices, according to a survey by the Zoological Survey of India (ZSI).
The report highlights the challenges faced by several endemic and migratory fish species in the region and underscores the urgent need for conservation measures to protect aquatic biodiversity.
Decline of native fishes
The ZSI survey identified sand mining as a major threat to breeding grounds of game fish species such as Labeo fimbriatus, Tor khudree, Pangasius pangasius, and Silonia childreni. These species rely on small streams and tributaries for spawning, but mining activities destroyed these habitats, leading to a sharp population decline, particularly in the upper Godavari region. Similarly, pollution from untreated sewage in cities like Nasik, Nanded, and Kopargaon and waste from paper industries in Bhadrachalam severely affected aquatic environment.
Deforestation in the region exacerbated soil erosion and siltation, further degrading water quality. The construction of dams and barrages created additional barriers to the migratory routes of fish, preventing species such as Tor and Anguilla from accessing breeding and feeding grounds. The lack of fish ladders on these structures further compounded the problem. Overfishing, both of target and by-catch species, also contributed to decline of native fish populations.
The study on fishes particularly in Godavari river emphasised the need for immediate conservation efforts. Experts recommend the establishment of fish sanctuaries along critical stretches of Godavari, such as downstream of the Gangapur and Vishnupuri dams, Nanded, and its confluences.
Ban unscientific fishing
These sanctuaries would include afforestation of riverbanks to improve soil and habitat quality. They also stressed banning unscientific fishing practices like the use of dynamite, toxic plants, and electric currents.
The study also warned of the impact of climate change on fish habitats, including reduced water flow during dry seasons and habitat loss due to variability in rainfall patterns.