UTTAR PRADESH JOURNAL OF ZOOLOGY

The Vamsadhara estuary (Kalingapatnam coast, Srikakulam district, Andhra Pradesh) is a biologically productive estuarine system supporting diverse ichthyofauna and important artisanal fisheries. This study synthesises hydrographic conditions (salinity gradients, temperature regimes, dissolved oxygen, turbidity, and freshwater discharge) and their influence on fish community composition, seasonal recruitment patterns, and fishery yields. We compiled field surveys, recent species checklists, fisheries landing data, and hydrological records up to January 2026 and combined them with satellite-based observations and local socio-economic assessments. Our synthesis shows that estuarine hydrography — driven by seasonal monsoon river discharge (Vamsadhara and upstream catchment dynamics), tidal mixing, and episodic weather extremes — structures ichthyofaunal zonation, nursery use by marine migrants, and seasonal shifts in species assemblages. More than 90 taxa are recorded from the Kalingapatnam freshwater–tidal stretch, with Perciformes, Siluriformes and Clupeiformes prominent in catches and estuarine samples. Salinity stratification and turbidity peaks during monsoon months correspond to higher juvenile abundance of estuarine-dependent species and influxes of shrimp post-larvae, while low-flow dry months favour marine migrant exit and adult feeding aggregations. Fisheries landings and socio-economic records reveal that artisanal gears (gillnets, stake nets, ring seines) are tailored to these seasonal dynamics; however, shifts in seasonal hydrography (e.g., altered monsoon timing and river discharge variability) have produced interannual variability in landings and livelihood risk. We conclude that maintaining estuarine connectivity, managing upstream flow regimes, and integrating hydrographic monitoring into fishery management are essential to sustain biodiversity and local fisheries. Key research priorities include long-term hydrographic time-series, fine-scale nursery habitat mapping, and adaptive fisheries governance that accounts for hydrological variability.