Vresen is a nationally designated game reserve.
The small remote island Vresen and the adjacent sea area are situated in the northeastern corner of Geopark the South Funen Archipelago, north of Langeland, in the central part of Storebælt (Great Belt).
Vresen constitutes the remains of a formerly larger moraine island that is now reduced to an islet with an area of 0.04 km2 consisting of sand and stones. The island was inhabited until 1922.
The whole area forms part of Storebælt, which is characterized by the fact that there is a convergence between salt water from the sea of Kattegat and water with lower salt content from Østersøen (the Baltic Sea).
Vresen is a breeding place for cormorants (Phalacrocorax carbo) and gulls. The mussel beds around Vresen are a very important feeding area for the Common Eider (Somateria molissima), and the area is also an important resting place for Graylag Geese (Anser anser). The rare shorebirds Ruddy Turnstone (Arenaria interpres) and Purple Sandpiper (Calidris maritima) are often seen in large numbers. The sea around Vresen is a very important habitat for the harbour porpoise (Phocoena phocoena). Seals often rest on the shores of Vresen and on stones around the island.
The area has a very high value due to its importance to sea mammals, eiders and resting shorebirds.
Protection and legislation
Vresen is protected, along with the central part of Storebælt, under the international Natura 2000 protection no. 116, habitat area no. H100 and Bird Directive no. F73.
The aim is to protect the large and shallow sea area, which has very important occurrences of reefs and is an important habitat for the harbour porpoise (Phocoena phocoena) and eiders (Somateria mollissima).
The area is also protected under a national law that protects various types of nature.
The Vresen Wildlife Reserve comprises 1.23 km2 and consists of a sea area and the island of Vresen, which is 0.04 km2 and has a length of just over a kilometre.
In order to protect the birdlife, access is prohibited on the island of Vresen and at a distance of 300 metres from the island from 1 October to the 30 June.