South Thames Estuary and Marshes are nationally scarce plants on dykes, and the diverse invertebra include nationally rare beetles, flies and true bugs. South Thames Estuary and Marshes South Thames Estuary and Marshes is a biological Site of Special Scientific Interest which stretches between Gravesend and the mouth of the River Medway in Kent. Part of it is a Nature Conservation Review site, Grade I, and part is a Royal Society for the Protection of Birds nature reserve. It is part of the Thames Estuary and Marshes Ramsar internationally important wetland site and Special Protection Area under the European Union Directive on the Conservation of
Oldfield Estuary Oldfield Estuary Oldfield Estuary is an estuary in the Goldfields-Esperance region of Western Australia. The estuary has a length of and is no wider than with a total area of approximately . The estuary has a main basin area of about and the rest is flood and tidal delta. The Oldfield River and the Munglinup River both discharge into the estuary. Uncleared bushland surrounds the estuary which has high dunes to the east and low sediments to the west. The lagoon is filled with river sediment to the north and beach sand to the south with a long high sandbar