Short description of the reef Nienhagen

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The reef is located in the Southwestern part of the fishery protected zone (FSG) of the LFA at a water depth of 11 to 12m. The investigation area is located about 8 km to the west of Warnemuende and to the north of the Baltic seaside resort Nienhagen, in about 1.5 km distance from the shore. The licence of the river and shipping police to install a big reef in the fishery protected zone Nienhagen and the utilisation contract were granted by the Water and Shipping Authority (WSA) Stralsund at the beginning of the project. In addition, a positive expert's report issued by the State Office for Fishery, water law permission and environmental law permission of the StAUN Rostock are available.

The "Artificial reef - Nienhagen" comprises of about 1,400 concrete elements and about 2500 t of natural stone and covers a surface of about 50,000 m². Thus, about 18,000 m² additional area for vegetation and multiple hiding places were created. 130 concrete rings were assembled on two fields, arranged in two layers, as well as 720 tetrapodes of 2t weight, also on two fields and piled up in three layers. 220 reef cones were installed in seven groups of about 25 to 30 items each on the Eastern flank of the investigation area, one additional to the west of the piling fields. In addition, 109 tetrapodes of 6t weight were placed in 10 to 12.5 m distance from each other, 40 of them on the Southern, 60 of them on the Western flank of the investigation area, 9 more items at the North-eastern part of the investigation area. The installation of flexible structures into the detached 6-ton-tetrapodes aims to create the maximum possible set of structures with a large volume to provide protected areas for fishes.

Nettings with 100 mm long mesh sides and 5 mm thick threads that are embedded horizontally (dimensions: 9 m x 9 m) with a 60l lifting body placed in central position but also vertically (dimensions 2 m x 8 m) between the 6-ton-tetrapodes. In addition, linen collectors were installed on the piled-up concrete rings and the 2-ton-tetrapodes as well as on the reef cones. These collectors, serving as compensation structures for larger algae, consist of 10 to 20 mm thick linen which is 2.5 to 3 metres long, a 3 to 10 l lifting body and hose stoppers in 50 cm distance to avoid a sliding off from the mussel vegetation. In the course of the investigations it turned out that the anchoring of the horizontal nets was not able to cope with the natural forces. Consequently, the lifting bodies (60 litre barrels) were removed from the horizontal nets in the investigation area in 2005. The nets remain fixed to the sea bed with 100 reef cones, 100 tetrapodes and 500 t natural stone as settlement substrate between the 6-ton tetrapodes.

A telemetry pylon that is needed as the technical basis for underwater observation and data remote transfer was placed in central position. Vegetation racks and special lifting bodies in and on the structures enable investigations of vegetation and algae problems.


Letzter Fischereieinsatz im Rahmen des Riffprojektes

Wir können nicht sagen, dass die Ostsee tot ist! Riffe sind wie Oasen in der Ostsee! Hier blüht das Leben! mehr

26.08.2022 I Thomas Mohr



02.12.2021 I T. Mohr

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The Reef

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Deutschland Land der Ideen – Ausgewählter Ort 2011

Third-party fund projects supported by the European Fishery Fund (EFF) of the European Union and the Ministry of Agriculture, Environment and Consumer Protection Mecklenburg-Vorpommern