Rivers up and down the north coast of New South Wales have been hammered again, just three years after devastating floods hit the Northern Rivers and Hawkesbury-Nepean Valley.

The events of 2022 sparked our latest research into the estuaries of NSW. These special places, where the rivers meet the sea, are teeming with life. Now – for the first time – we can reveal what lives where, in maps based on tell-tale traces of DNA.

Together with Indigenous rangers from six language groups, we surveyed 34 estuaries to capture evidence of living species – everything from microbes to fish, plants and mammals.

We were surprised to find platypus in places they had not been seen for years. We also identified elusive native species such antechinus and rakali, and 68 invasive or pest species including cane toads – spreading further south than previously thought.

This catalogue of species in NSW estuaries can be used by authorities and scientists – but anyone, anywhere can explore the map online.

First Nations Peoples have long recognised the vital importance of the areas where land meets sea. Estuaries are have provided

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