Reef Nienhagen
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The Nienhagen Reef (also known as the "Nienhagen Artificial Reef") is an artificial reef created for research purposes near the Baltic Sea resort of Nienhagen . It is located in the southwestern part of the fishery protection area (FSG) of the State Research Center for Agriculture and Fisheries (LFA) at a depth of 11 to 12 m. The study area is located around 8 km west of Warnemünde and north of the Baltic Sea resort of Nienhagen at a distance of around 1.5 km from the shore. The reef consists of around 1400 concrete elements and around 2,500 tons of natural stone and covers an area of around 50,000 m². This created around 18,000 m² of additional vegetation and numerous shelter options.
Reasons for an artificial reef in the Baltic Sea
The fishing resources have a decreasing trend not only in the western part of the Baltic Sea . Traditional management measures such as minimum landing lengths, minimum mesh sizes, temporary fishing bans and temporarily closed areas have not achieved sufficient success. The “Artificial Reef Nienhagen” project (2002–2008) looked for alternative ways of stabilizing the stocks of commercial fish. As a result, a large artificial underwater habitat was created in front of Nienhagen as a recruiting, growing and resting zone for the fish species that occur here.
The reef elements
| elements | description |
|---|---|
| 2-ton tetrapod |
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| 6 ton tetrapod |
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| Reef cone |
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| Concrete ring |
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| Algae table |
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| network |
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| Vegetation frame |
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construction
The reef is laid out on a rectangular area. The side lengths are each approx. 200 m. Almost all concrete and natural stone elements are housed within this rectangle.
- 130 concrete rings on two fields in two layers
- 720 2-tonne tetrapods on two fields in three layers
- 220 reef cones in 7 groups (25-30 per group)
- 1 group west
- 6 groups east
- 109 6t tetrapods individually (distance of 10–12.5 m)
- 40 pieces south
- 60 pieces to the west
- 9 pieces northeast
- 12 seaweed tables east
- 2500 t of natural stone in two fields
- 2000 t field north
- 500 t field to the southwest
- flexible structures (lines and nets) between the individual 6-tonne tetrapods (west)
- horizontally and vertically attached nets between the 6-tonne tetrapods
- Line collectors on stacked concrete rings, 2-tonne tetrapods and reef cones
- 5 vegetation racks
- 3 stacks of concrete pipes
A research platform is placed in a central location, which is required as a technical basis for fishing studies, underwater observation and remote data transmission.
Reef Chronology
| year | event |
|---|---|
| 1994-1995 : | Study “The biological and fishing situation in the coastal waters of MV; Limits and possibilities of influencing them by artificial reefs " |
| 1996-1999 : | Planning and preparatory studies for the construction of an artificial reef in the coastal waters of MV; Establishment of a test reef |
| 1996-1998 : | Design, project planning, implementation and initial use of a tilt mast as a telemetric long-term measuring and observation station on the Nienhagen test reef |
| 1999-2000 : | Long-term test of the telemetry mast; Improvements in the energy and camera concept |
| 2002-2008 : | Joint project “Increasing the fishing value of sea areas off the coast of Mecklenburg-Western Pomerania through the establishment of artificial underwater habitats. Construction of a large reef in the Nienhagen fisheries reserve " |
| 2009–2012 : | "Reefs in the Baltic Sea" and "Testing an aquaculture project for the production of the red alga Delesseria sanguinea on the Nienhagen reef and further studies for the economic utilization of the sulfated polysaccharides of this alga" |
During the study period between 2002 and 2008, biodiversity tended to increase. In 2003 a total of 20 different fish species were sighted in the reef area. In 2005 it was already 25 and in 2006 it was already 29. The main fish species on the reef are cod , flounder , turbot , dab , whiting , rock perch , sand eel , sea scorpion , sea hare , herring and gobies . Since 2007, seven new fish species were detected: Köhler , mullet , poor cod , pipefish , coalfish , red gurnard . Rare specimens such as B. Eel mother and hornfish were not included in the statistics, as they could only be assumed to be randomly distributed. The dominant species is the cod. With the help of cod markings, a recovery rate of 16.8% was determined. This result was unexpectedly high and speaks for the loyalty of the cod in the reef. On average, the biomass caught between 2003 and 2008 was 33 kg per day of catch . Here, too, there was a tendency to increase. In 2004 it was 29 kg and in 2006 it was 43 kg.
The observations of the vegetation in the area of the reef elements showed a rapid increase in biomass. Four weeks after the first elements were sunk, the first starfish settled . Hydroid polyps were found sporadically. Red algae appeared very early and after eight weeks the surfaces were almost completely covered with a brown detritus layer. This consisted of mud tubes of small polychaetes . After two months came the first mussels , barnacles and polyp stages of the ear jellyfish . The stock of starfish increased rapidly until 2007. The main food of the starfish is the mussel. This led to seasonal fluctuations in the starfish and mussel stocks (fewer starfish = more mussels). After seven months, the proportion of diatoms increased and an increase in the number of species of polychaetes and bryozoa was detected. The total biomass rose rapidly by December 2005 to 2500 g / m². By 2008 this had stabilized at 2100 g / m².
On July 31, 2010, the previously existing telemetry mast was replaced by a new research platform. The 40 m² work surface with an office container is located 7 m above sea level and is fixed in the sea floor with three foundation piles at a depth of 12 m. Autonomous energy sources supply the research station with electricity. Three underwater and one surface cameras record what is happening on the reef. The data transfer to the mainland takes place via WLAN .
Research on the Nienhagen reef
The title of the fourth project phase (2009–2012) was reefs in the Baltic Sea and testing an aquaculture project for the production of the red alga Delesseria sanguinea on the Nienhagen reef and further studies for the economic utilization of the sulfated polysaccharides of this alga . Based on the project "Artificial Reef - Nienhagen" (2002–2008), the research work was continued under the new project title. New research methods are used. The research project was funded by the European Fisheries Fund of the European Union and the Ministry of Agriculture, Environment and Consumer Protection of the State of Mecklenburg-Western Pomerania and ran from January 1, 2009 to December 31, 2012. The project was extended to October 31, 2015. The State Research Center for Agriculture and Fisheries Mecklenburg-Western Pomerania is responsible for coordination.
aims
2002 to 2008
- Proof of the increase in fishing value
- Recording and evaluating the effects on species communities through artificial underwater habitats
- Recording the effects on the behavior of local fish stocks
- Conservation of fishing resources
- Recording the effects on stock structures and sizes of important fish stocks through concentration and protection mechanisms
2009 to 2012
- Determination of the length of stay of cod in artificial habitats and the migratory behavior of possible local cod stocks
- Determination of a possible improvement in the natural resettlement rate and a fishery upgrading of pouring and dumping points through the installation of artificial habitats
- Testing of a small-scale experimental facility for the rearing of the red alga Delesseria sanguinea as a step between laboratory and large-scale production facility
- Development of a marketable product based on Delesseria sanguinea and an easy-to-use control and analysis method for industrial production
Individual evidence
literature
Specialist literature
- State Research Center for Agriculture and Fisheries Mecklenburg-Western Pomerania: Artificial reef Nienhagen . In: Communications from the State Research Center for Agriculture and Fisheries Mecklenburg-Western Pomerania, Issue 38, Gülzow August 2007, ISSN 1618-7938
- State Research Center for Agriculture and Fisheries Mecklenburg-Western Pomerania: Annual report 2009 . In: Communications from the State Research Center for Agriculture and Fisheries Mecklenburg-Western Pomerania, volume 42, Gülzow April 2009, ISSN 1618-7938
- State Office for Agriculture, Food Safety and Fisheries: Fischerei & Fischmarkt in Mecklenburg-Vorpommern .
Daily newspapers
- North German Latest News : EU Reef Project for Dorsch & Co. , No. 128/57, June 5, 2009
- North German Latest News: Full Life on the Artificial Reef , No. 128/57, June 5, 2009
- Ostsee-Zeitung : Second concrete reef planned , June 5, 2009, Rostock edition
- Ostsee-Zeitung: Artificial reef gets research platform , June 5, 2009, Rostock edition
Web links
- Literature about Riff Nienhagen in the state bibliography MV
- official website for the Riff-Nienhagen project
Coordinates: 54 ° 10 ′ 30 ″ N , 11 ° 56 ′ 36 ″ E