NLDelta consists of a joined-up system of flourishing nature reserves. The water-rich ‘jungle’ of the Biesbosch is a unique freshwater-tidal zone, with a network of creeks, islands and morasses. Connected to this area is the Haringvliet which forms a natural transition from river to sea, and has a natural history which is quintessentially Dutch. This includes include shellfish beds, migratory fish, bird-rich mudflats and its centre-piece, the almost uninhabited island nature reserve of Tiengemeten.
Ebb and flood, saltwater and freshwater, high and low water: the dynamics of the water determine the ecosystem here. Tidal ranges of between 30 to 80 cm are not uncommon throughout the delta and up to 50 kilometres upstream.
The Rhine-Meuse estuary is a rich and unique ecosystem. The delta is an indispensable link in the migratory routes of birds, providing places for foraging and stopovers, as well as for wintering or breeding. Wading birds and spoonbills, avocets and godwits and birds of prey, such as the white-tailed eagle and osprey, can commonly be seen in the delta.