Teil C - Annex 
71 
Laptop/external hard drive: 
• Sufficient storage capacity 
• It must be taken into consideration that the various detection systems work with different 
operating systems (e. g. Avisoft with Windows, Batcorder with Macintosh). 
Analysis equipment for bat call identification: 
• Sound analysis software (e. g. Avisoft SAS-Lab Pro, Pettersson BatSound) 
The following system provides an example for recording of bat calls in the offshore area: 
Sample configuration: 
• Detector: Avisoft UltraSoundGate 416h 
• 3 x P 48 Electret Ultrasound Microphone (Avisoft Bioacoustics/Knowles FG) with micro 
phone heating in anti-exposure casing 
• Shielded microphone cable with shielded 5-pin XLR connector 
• Avisoft Bioacoustics piezo-electric signal generator (a piezo-electric signal generator allows 
for automatic control signals of pre-defined frequency and volume to be emitted at any time 
in order to check the microphone’s efficiency) 
• Laptop and external solid state hard drives 
• Avisoft SAS-Lab Pro. 
Bat call survey 
General procedure: 
Call activity recording takes place in fixed anchor position parallel to night-time migratory bird 
call recording in the periods mid-April to May and mid-August to October in windless nights 
(up to 3 Bft). Principally, bat call recording takes place from sunset to 2 hours after sunrise 
(civil twilight). Continuous call activity recording must be ensured! 
Basically, three external ultrasound microphones are installed, following the standards as 
given below. The installed detector system automatically records bat calls. The data is stored, 
read after each trip and brought to the office for analysis. 
Bats that are sighted or land on the ship during the bird migration survey (see table 3.2.2) are 
recorded accordingly (if possible, down to species level). Anchor position and weather infor 
mation are copied from the bird migration survey data. 
Installation of survey equipment: 
The survey equipment (computer, detector system) is set up protected from the weather. The 
microphones that are installed externally on the ship are connected to the detector system by 
microphone cables and fastened in a manner protecting them from the weather (wind/waves/ 
rain) (Suggestion: the microphone may be inserted in, for example, a PUR tube, which ex 
tends beyond the microphone by about 2 cm. The tube ends should be sealed with water 
proof tape/silicon sealant to protect also the plug connections). 
Depending on conditions on the ship, three microphones should be installed at a maximum 
height of 5 m above the water surface (e. g. on the survey ship’s rail). Ideally, the microphones 
should not be installed near the ship’s generator and radar. One microphone each should be 
installed on the port and starboard side of the ship. A third microphone points to the stern, 
angled downwards at 45° and, where necessary, should be equipped with a reflector panel.