01830nas a2200205   4500008004100000022001400041245010700055210006900162260001600231300001600247490000700263520117500270100002201445700002001467700002101487700002201508700002101530700001801551856005501569       2013                        eng d  a0340-544300aMultimodal signaling in the Small Torrent Frog (Micrixalus saxicola) in a complex acoustic environment0 aMultimodal signaling in the Small Torrent Frog Micrixalus saxico  cJan-09-2013  a1449 - 14560 v673 a<p>Many animals use multimodal (both visual and acoustic) components in courtship signals. The acoustic communication of anuran amphibians can be masked by the presence of environmental background noise, and multimodal displays may enhance receiver detection in complex acoustic environments. In the present study, we measured sound pressure levels of concurrently calling males of the Small Torrent Frog (Micrixalus saxicola) and used acoustic playbacks and an inflatable balloon mimicking a vocal sac to investigate male responses to controlled unimodal (acoustic) and multimodal (acoustic and visual) dynamic stimuli in the frogs&#39; natural habitat. Our results suggest that abiotic noise of the stream does not constrain signal detection, but males are faced with acoustic interference and masking from conspecific chorus noise. Multimodal stimuli elicited greater response from males and triggered significantly more visual signal responses than unimodal stimuli. We suggest that the vocal sac acts as a visual cue and improves detection and discrimination of acoustic signals by making them more salient to receivers amidst complex biotic background noise.</p>
1 aPreininger, Doris1 aBoeckle, Markus1 aFreudmann, Anita1 aStarnberger, Iris1 aSztatecsny, Marc1 aHödl, Walter  uhttp://link.springer.com/10.1007/s00265-013-1489-6