Wet season freshwater flows deliver catchment nutrients (terrestrial and freshwater) to tropical estuaries that stimulate productivity and support consumers. However, the impact of flows on species in the adjacent nearshore is unclear. We investigated how freshwater flows affected the biochemical fingerprint, and by extension the resource use patterns, of the commercially important penaeid prawn, Penaeus merguiensis, in estuarine and nearshore habitats in the tropical Gulf of Carpentaria, Australia by comparing trace element and δ