Guidance Zeeland delta, Waddenzee and dammed inlets

Index section Zeeland delta, Waddenzee and dammed inlets

• Oosterschelde tidal flats
• Eelgrass in the Waddenzee and Zeeland delta
• Breeding seabirds in the Zeeland delta
• The lobster and the damming of the Oosterschelde

Introduction

The damming of inlets, particularly the Zuiderzee, Haringvliet and Grevelingen, has had huge repercussions for the Waddenzee and Zeeland delta. It has removed tidal influence and has resulted in the water behind the dams becoming less saline. The Grevelingen is still classified as a tidal area because of its salinity, but in other areas, particularly the Oosterschelde, tidal influence has diminished. The damming of inlets has reduced the area of saltmarsh in the Zeeland delta and also the area of shallow flats that are important for birds. Ranker vegetation is encroaching in the saltmarsh, as a result of vegetation succession.

Various human interventions have caused much of the natural dynamics of the Zeeland delta to disappear, with the result that pioneer situations are less common. As a result, pioneer species like the Kentish plover and little tern are endangered.

The beds of eelgrass have all but disappeared from the Zeeland delta and Waddenzee, and with them an entire ecosystem has been lost.

Some species have profited from the changes in the Oosterschelde that occurred after the storm surge barriers were constructed. They include the lobster, which likes the increased salinity, reduced currents and clearer water, and the sea squirt. And in the Oosterschelde certain exotics have greatly increased in number.