Figure 5. Spectrogram (i.e., frequency kHz over time in seconds) of Houston Toad (A. houstonensis) vocalizations collected within Bastrop County, Texas, USA.
When multiple individuals are present advertisement calls vary in frequency (kHz; Y-axis) demonstrating behavioral modulation of this characteristic. Spectrogram generated in Kaleidoscope 4.3.1 (Wildlife Acoustics). Audio visualized in this figure was not used within our analysis of advertisement call comparison.