Spectrogram of an ultrasonic recording made with the microphone Dodotronic Ultramic 384. Besides echolocation and social calls of Leisler’s Bat Nyctalus leisleri there is a frequency band around 8 kHz, representing stridulation sounds of Great Green Bush-cricket Tettigonia viridissima. BRITZ03, 16 July 2021, 21:50 h; spectrogram settings – downsampling to 192 kHz, FFT size 1024, Frame size 50 %, Window Hann, overlap 87.5 %.