Diversity, Composition and Conservation Status of Ichthyofauna in Dibru River: an Important Habitat for Gangetic Dolphin in Assam

The Dibru River, a significant tributary of the Brahmaputra, traverses the Tinsukia and Dibrugarh districts of Assam. It serves as a vital resource for local communities, many of whom rely heavily on fishing for their livelihoods. However, intensive fishing pressure is believed to be a major driver of declining ichthyofaunal diversity in the region. This study aims to assess the diversity, composition, population trends, and economic significance of fish species inhabiting the Dibru River. Data were collected through experimental fishing at three designated sites and supplemented by surveys of fish sold nearby landing stations, including species not captured during field sampling. A total of 76 fish species were documented, representing 51 genera, 25 families, and 9 orders. The family Cyprinidae was the most represented (16 species), followed by Danionidae (12), Bagridae (7) and Channidae (6). According to the IUCN Red List assessment, 87% of the recorded species are classified as Least Concern (LC), 6% as Near Threatened (NT) and 3% each as Vulnerable (VU) and Endangered (EN), with 1% listed as Data Deficient. Of the identified species, 28 are primarily consumed as food, 7 possess exclusive ornamental value, and 41 serve both culinary and decorative purposes. During the study, dolphins were sighted across the years at different sites along the river. This comprehensive documentation of ichthyofaunal diversity is pivotal for guiding future research and conservation efforts, particularly in safeguarding the endangered Gangetic dolphin, which inhabits the same riverine ecosystem.

@article{priyanka2026,
  author  = {Priyanka Sarkara, Nazimur Rahman Talukdara, Parthankar Choudhurya* and S.P. Biswasb},
  title   = {{Diversity, Composition and Conservation Status of Ichthyofauna in Dibru River: an Important Habitat for Gangetic Dolphin in Assam}},
  journal = {Journal of Bioresearch},
  year    = {2026},
  volume  = {5},
  number  = {2},
  pages   = {17-28},
  doi     = {https://doi.org/10.5281/zenodo.18278720},
}