This study documents the development of a benthic reef community on the foundations of the first Dutch offshore wind farm in the first years after construction. The wind farm was built in 2006 and has been in operation since January 2007. The turbine monopile foundations and the rocks around the foundations that serve as scour protection, form a new hard substrate habitat in an environment previously dominated by soft sandy substrates. Five years after commissioning of the wind farm a total of 55 different taxa (including several non-indigenous species) were identified using video footage and samples collected by divers. The intertidal zone was characterised by a band of green algae, different species of barnacles, oysters and small blue mussels. In the subtidal zone, a patchy but generally thick layer of blue mussels was present to circa 10-12 m depth with associated species such as starfish, crabs and various polychaetes. At greater depth, benthic communities were dominated by small crustaceans, anemones and ringed tubularia. The most dominant species on the scour protection were plumose anemones, small crustaceans and the encrusting sea mat. Total densities of hard substrate species increased over the study period to circa 28,000 individuals per m2 on the monopiles and circa 2,500 individuals per m2 on the scour protection layers. Total biomasses varied between circa 450 and 1,400 g AFDW per m2. The new hard substrate communities can form a valuable food source for fish and bird species.
The Development of Benthic Communities on Hard Substrates within OWEZ, the First Dutch Offshore Wind Farm
Title: The Development of Benthic Communities on Hard Substrates within OWEZ, the First Dutch Offshore Wind Farm
September 21, 2012
Conference Name: International Council for the Exploration of the Sea
Conference Location: Bergen, Norway
Notice: This material may be protected by Copyright Law.
Noordzee Wind (2012). The Development of Benthic Communities on Hard Substrates within OWEZ, the First Dutch Offshore Wind Farm. Paper Presented at the International Council for the Exploration of the Sea, Bergen, Norway.