46 
Teil C - Annex 
Equipment standard Baltic Sea: Otter trawl (wind farm trawl) 
The standard net for the Baltic Sea as prescribed by the StUK is an otter trawl. The net shown 
in the drawing below has been developed for ecological offshore wind farm surveys. The trawl 
consists of an upper belly and a lower belly. It has a total length of about 40 m (incl. cod end) 
and a circumference of 32.6 m. Details of the required net material, cut, and assembly are 
given in fig. 6. The codend is lined with an inside webbing (inner codend) with 38 mm mesh 
size (20 mm mesh bar). Details of the set of bridles are shown in fig. 7, of the head and foot 
ropes in Fig. 8. 
At the projected wind farm depths, the vertical opening of the net will be about 1.5 m on aver 
age and the horizontal opening between the wing tips about 10 m. 
Figure 6: Wind farm trawl: material, cut, and assembly of the net.