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Part B - Technical instructions 
Table 1.6: Investigation of growth and demersal megafauna on underwater structures. 
Operation phase 
Objectives 
Investigation of growth (macrophytes and macrobenthos) and demersal megafauna 
on piles, foundations and scour protection. 
Scope 
Once a year in autumn. 
Survey of piles, foundations and scour protection on at least two wind turbines per 
foundation type. 
Timing 
In the third and fifth year of the operation phase. 
Method 
Sampling strategy: 
• The sampling dates are to observe the same limited time frame each year. 
• The seasons are defined as follows: Autumn: 15.08.-15.11. 
• Up to 10 m water depth, pile survey to be made by research divers. Taking of 
3 quantitative scratch samples (20 cm x 20 cm) each at three depths (1 m, 5 m, 
10 m- mean tidal high water) for the quantitative assessment of growth community 
and quantification of species. 
• At greater depths, the foundations and scour protection survey and determination 
of species of mobile, demersal megafauna (> 2 cm) shall be effected by consulting 
the video footage of the technical construction monitoring (see Standard “Design of 
Offshore Wind Turbines”, Table 1, BSH 2007). 
• Biomass shall be determined as wet weight per species 
(according to ISO/DIS 16665, Annex C). 
Moreover, the following information must be determined and documented: 
• Hydrographic (T, Sal, 0 2 ) and meteorological data. 
Presenta 
tion of 
results 
Documentation of condition and modification by illustration of: 
• Total number of individuals per area/number of individuals per species and area 
(species table). 
• Total biomass per area/biomass per species and area. 
• Dominance structure (related to number of individuals and biomass). 
• Species specific and absolute coverage. 
• Comparison with natural hard-substrate communities (if available).