ANT Oosterschelde: Long-term trends of waders and their dependence on intertidal foraging grounds

The ANT study (“Autonomous Negative Trend” of the Oosterschelde estuary) aims to deliver the scientific support needed to assess the feasibility and affordability of the different conservation goals of Natura 2000. The main aim is to advise in which locations in the Oosterschelde estuary what kind of measures can be taken in order to meet (part of) the Natura2000 conservation goals for quality and quantity of the habitat of protected shorebird species. To meet this aim we first need to get insight in how the birds use the intertidal areas, and what factors determine their presence. That we do not fully understand the autonomous trends in bird numbers is clear from a discrepancy between expected and observed trends in wader numbers. Although we would expect to see declining wader numbers because of the ongoing erosion of the intertidal, we in fact see steady and even increasing numbers of several species. The present study aims to describe and explain observed trends in bird numbers by exploring relationships between bird numbers and biotic and morphological changes in the intertidal area of the Oosterschelde estuary.