The Owenboy River flows through County Cork in southwest Ireland, draining into Cork Harbour as a tidal estuary near Crosshaven and the broader harbour area. The lower reaches of the river transition into estuarine habitat where freshwater mixes with tidal saltwater, creating a dynamic and ecologically rich environment. The estuary and its surrounding mudflats, sandflats, and wet grasslands are recognized as a National Heritage Area (NHA), reflecting the significant ecological value of this waterway and its riparian corridor. The variable salinity throughout the lower river and estuary, driven by both riverine inputs and tidal currents, shapes the habitat and the species that can be targeted here.