Multi-seasonal eDNA metabarcoding highlights a resurgence in fish diversity across a severely impacted estuarine ecosystem

This dataset represents a 12-month environmental DNA (eDNA) survey conducted in the Mersey Estuary, United Kingdom, capturing seasonal patterns of fish diversity across the system. Sampling was performed at 10 strategically selected sites spanning approximately 60 km of the estuary, providing comprehensive spatial coverage of the waterway. Fish communities were characterised via metabarcoding using Tele02 primers, which target a conserved region of the mitochondrial 12S rRNA gene, enabling sensitive detection of multiple species from water samples.The dataset provides insights into temporal and spatial variation in fish assemblages across a historically degraded and now recovering ecosystem.