72 
Teil C - Annex 
Calibration of the bat detector: 
All available detector systems allow for a broad range of calibrations; it is therefore difficult to 
provide general calibration standards. Generally, it must be ensured that the entire species 
spectrum potentially occurring in the assessment area is captured. By way of example, the 
Avisoft system calibrations are presented in the following: 
in the offshore area, standardised specifications apply to calibration of bat detectors of the 
Avisoft system, which (slightly altered) shall provide a guideline for bat surveys in the offshore 
area (BMU project “Reduktion des Kollisionsrisikos von Fledermäusen an Onshore-Windener- 
gieanlagen (RENEBAT II)”, FKZ: 0327638C, Period: 01.09.2011-31.08.2013). If survey sys 
tems other than the Avisoft system are used in the context of offshore surveys, it must be 
ensured that they correspond to the requirements and calibrations as specified here 
(cf. Fig. 2).