The Site is an extensive system of river, seasonal creek, tidal mudflat and floodplain wetlands, and is the best example in the Tanami-Timor Sea Coast bioregion of wetlands associated with a tropical river system’s floodplain and estuary. The area known as the False Mouths of the Ord is the most extensive mudflat and tidal waterway complex in Western Australia, while the wetland grass/herblands at Parry Lagoons are the most extensive vegetation community of this type in the State. 15 of the 19 species of mangrove found in Western Australia have been recorded within the Site. It is a nursery, feeding and breeding ground for a variety of migratory birds and local waterbirds, fish, crabs, prawns and crocodiles. The Site regularly supports 1% of the population of plumed whistling duck (Dendrocygna eytoni) and little curlew (Numenius minutus); and it supports threatened species including the critically endangered freshwater sawfish (Pristis microdon) and green sawfish (Pristis zijsron), and the endangered Australian painted snipe (Rostratula australis); it is also one of only two known habitats in Western Australia of the critically endangered Northern river shark (Glyphis garricki). A flatback turtle (Natator depressus) rookery is located at Cape Domett, immediately north of the Ramsar Site.