First Record of the Ichthyofauna in the Seasonally Flooded Baraila Wetland, India: In Relation to the Ecological Health of the Wetland

The Baraila wetland, located in the middle Gangetic plains of India, is among the globally recognized habitats for migratory birds. Despite its ecological importance, the wetland is predominantly impacted by land encroachment, habitat degradation, agricultural expansion, an infestation of weeds, and frequent droughts leading to poor wetland health and associated biodiversity loss. Therefore, the present study aimed to address unexplored research on the fish diversity and its relation with the ecological health of the Baraila wetland. The wetland water was alkaline, with low to highly turbid (0.26 to 341 NTU) water conditions. Moreover, the mean level of Dissolved Oxygen was beyond the threshold of 5 mg/L for aquatic fauna. The study was conducted from April 2022 to October 2023 at the major landing sites of the wetland. The result revealed the presence of 33 fish species across 14 families and 8 orders, with Cypriniformes being the most dominant order. Among these species, 2 were classified under the Vulnerable (VU) category, namely Wallago attu and Channa orientalis, and marked Cyprinus carpio as the only exotic fish species. It also recorded the dominance of moderately tolerant to tolerant species of small Indigenous fish. The majority of the fish with omnivorous feeding behavior highlights the poor health of the wetland. In addition, the highly submerged vegetation, nearly dry to shallow water depth, and turbid environment have favored the fauna of small size that can thrive in such conditions. The pioneer information on fish diversity status will help the stakeholders to design and implement suitable conservation measures for the Ichthyofauna of the critically endangered Baraila wetland.