Part B - Technical instructions 
15 
Part B - Technical instructions for surveys of features of conser 
vation interest 
Features of conservation interest 
Technical details of the investigation and monitoring to be carried out in order to protect the 
features of conservation interest, i.e. benthos, fish, birds and marine mammals, will be pro 
vided in the following. The scope and targets of the investigations, methods to be used, and 
the evaluation basis are described for each of the features of conservation interest. 
1 Benthos 
The benthos investigations and monitoring comprise: 
• Investigation of the sediment and habitat structure and their dynamics using side scan 
sonar (Table 1.1). 
• Video survey of epifauna, macrophytes and habitat structure (Table 1.2). 
• Grab sampling survey of infauna (Table 1.3). 
• Beam trawl survey of epifauna (Table 1.4). 
• Installation-based grab sampling survey of infauna (Table 1.5). 
• Investigation of growth and demersal megafauna on the underwater construction structure 
(Table 1.6). 
• Investigation of benthos and habitat structures in the context of installation of cable routes 
for connecting offshore wind farms (Table 1.7). 
Additionally, the sediment properties per grab sampler (short core sampler 4.5 cm inner 
diameter, 6 cm penetration depth) have to be determined: 
• Grain size distribution (silt/clay, fine sand, medium-grained sand, coarse sand, gravel/ 
rubble) (according to DIN EN ISO 14688-1-2003). 
• Loss on ignition (according to DIN EN-12879:2001-02). 
During the above investigations, measurements of salinity, temperature and oxygen levels 
(according to UNESCO 1988) have to be carried out at the sea surface (- 0.5 m) and near the 
seabed in order to obtain a representative picture of the hydrographic situation in the area. 
The results of the sedimentological and benthological investigations should be combined in a 
single study. 
If possible, the benthos investigations should be carried out at the same time as the fish 
investigations, but mutual disturbance should be avoided. 
The application documents for the wind farm project must include area demarcation of the 
habitats protected by § 30 Section 2 p. 1 No. 6 BNatSchG on the basis of the respectively 
valid German Federal Agency for Nature Conservation (BfN) mapping guidelines for the Ger 
man EEZ (where available). 
In the third year after the end of the baseline study, the area studies of benthos (see Table 1.3 
and 1.4) shall be resumed in this section for those areas, where installation of foundations and 
infield cabling has been completed. The studies follow the methodology of operation-phase 
monitoring.