Duinen Vlieland is a small island in the Wadden Sea, characterized by an extensive area of sand dunes, conifer crops and embanked brackish lagoons important for maintaining the biodiversity in the Atlantic biogeographic region. The Site was formerly part of Ramsar Site 1252 (Waddeneilanden, Noordzeekustzone, Breebaart) which was divided into six Sites following Natura 2000 borders in 2014. The Site is of particular importance for breeding and non-breeding bird species. Some of these, such as the common redshank (Tringa totanus robusta) and Eurasian spoonbill (Palatea leucorodia), gather in particularly high numbers. The Site plays also an important role in freshwater supply and shoreline stabilization. Land use is dedicated to tourism, conservation and research. The main threats to the Site are bird disturbance by air force military training and over-exploitation of groundwater.

The "Wadden Sea" Transboundary Ramsar Site was declared in 2015 and it includes 13 Ramsar Sites in Denmark, Germany and the Netherlands: Site No. 356 in Denmark; Sites No. 501, 537, 80, 81, 82 in Germany; Sites No. 1252, 289, 2212, 2213, 2214, 2215, 2216 in the Netherlands.