North Frisian Barrier Island is the collective term for three

barrier islands Barrier islands are coastal landforms and a type of dune system that are exceptionally flat or lumpy areas of sand that form by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a f ...

(outer

shoal In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body of water to near the surface. It ...

s) due west of the German

Halligen The ''Halligen'' (German, singular ''Hallig'', ) or the ''halliger'' (Danish, singular ''hallig'') are small islands without protective dikes. They are variously pluralized in English as the Halligen, Halligs, Hallig islands, or Halligen islands. ...

in the

North Frisian Islands The North Frisian Islands (''Öömrang'' and '' Fering'' frr, Nuurdfresk Eilunen, ''Söl'ring'' frr, Nuurđfriisk Ailönen, link=no, da, Nordfrisiske Øer, german: Nordfriesische Inseln) are the Frisian Islands off the coast of North Frisia. T ...

archipelago. The shoals act as natural

breakwater Breakwater may refer to: * Breakwater (structure), a structure for protecting a beach or harbour Places * Breakwater, Victoria, a suburb of Geelong, Victoria, Australia * Breakwater Island, Antarctica * Breakwater Islands, Nunavut, Canada * Br ...

for the Halligen and other islands closer to land. Uninhabited, they remain one of the few areas in the

Wadden Sea The Wadden Sea ( nl, Waddenzee ; german: Wattenmeer; nds, Wattensee or ; da, Vadehavet; fy, Waadsee, longname=yes; frr, di Heef) is an intertidal zone in the southeastern part of the North Sea. It lies between the coast of northwestern conti ...

that are unaffected by direct human activity. The shoals from north to south are: The shoals are subject to constant change and are slowly moving towards the mainland coast to the east. This changes both their location and surface area. During the last 50 years, all three shoals benefitted from their increasing area but their individual development was very diverse. In total, 43.5 million m³ of sand were eroded by wind and water on the west coasts of the shoals, whereas 32.4 million m³ were deposited at the eastern shorelines. Especially Japsand, which is the youngest and smallest of the three shoals, could thereby gain volume and was the fastest moving shoal. Numerical simulations by the

University of Kiel Kiel University, officially the Christian-Albrecht University of Kiel, (german: Christian-Albrechts-Universität zu Kiel, abbreviated CAU, known informally as Christiana Albertina) is a university in the city of Kiel, Germany. It was founded in ...

have shown the likelihood of a merger between Japsand and Norderoogsand until 2050. This would cover Hallig Norderoog in sand, as well as large areas of

mudflat Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal f ...

s which are still east of the sands as of today. The peak heights of the shoals reach about one metre above the average high tide. In summer, the dry sand is sometimes piled to

dune A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, f ...

s of several metres height. These are occasionally settled by Elymus grasses. Since 1999 though, an increasingly stable and diverse vegetation has been observed at the northern edge of Norderoogsand. The plant carpet helps to accumulate ever more sand, and so the peak dune of Norderoogsand was recorded with 3.50 metres in 2013. Because of this development, Norderoogsand has been called a new island. All three shoals are

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, or features of geological o ...

s and constitute an important resting area for

migratory bird Bird migration is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. Many species of bird migrate. Migration carries high costs in predation and mortality, including from hunting b ...

harbour seal The harbor (or harbour) seal (''Phoca vitulina''), also known as the common seal, is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere. The most widely distributed species of pinniped (walruses, eared se ...

s, and

grey seal The grey seal (''Halichoerus grypus'') is found on both shores of the North Atlantic Ocean. In Latin Halichoerus grypus means "hook-nosed sea pig". It is a large seal of the family Phocidae, which are commonly referred to as "true seals" o ...

s. Together with the ''Hooger Loch'' and ''Rummelloch-West'' gats, as well the Halligen of Norderoog and Süderoog, the shoals are a popular resort for seals and form one of the main

moulting In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...

areas of the

common eider The common eider (pronounced ) (''Somateria mollissima''), also called St. Cuthbert's duck or Cuddy's duck, is a large ( in body length) sea-duck that is distributed over the northern coasts of Europe, North America and eastern Siberia. It breed ...

. The shoals are part of the core zone of the

Schleswig-Holstein Wadden Sea National Park The Schleswig-Holstein Wadden Sea National Park (german: Nationalpark Schleswig-Holsteinisches Wattenmeer) is a national park in the Schleswig-Holstein area of the German Wadden Sea. It was founded by the Parliament of Schleswig-Holstein on 1 O ...

and must not be entered except for the northern areas of Japsand. In 1985, a light beacon was erected on Süderoogsand on a wooden framework. The device is

solar power Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Photovoltaic cells convert light into an electric current using the photovolta ...

ed and has a shelter for shipwrecked sailors.

Gallery

Image:Süderoogsand.png, NASA Satellite Image of Süderoogsand, the largest and southernmost sand bank, with Hallig Süderoog upper right Image:Seroog001.jpg, Süderoogsand with navigational light beacon

References

{{coord, 54, 30, N, 8, 29, E, display=title, region:DE_type:isle_source:dewiki North Frisian Islands New islands Barrier islands