The relevance of temporal cues in a fish sound: a first experimental investigation using modified signals in cichlids

International audiencePlayback experiments have been a useful tool for studying the function of sounds and the relevance of different sound characteristics in signal recognition in many different species of vertebrates. However, successful playback experiments in sound-producing fish remain rare, and few studies have investigated the role of particular sound features in the encoding of information. In this study, we set-up an apparatus in order to test the relevance of acoustic signals in males of the cichlid Metriaclima zebra. We found that territorial males responded more to playbacks by increasing their territorial activity and approaching the loudspeaker during and after playbacks. If sounds are used to indicate the presence of a competitor, we modified two sound characteristics, that is, the pulse period and the number of pulses, in order to investigate whether the observed behavioural response was modulated by the temporal structure of sounds recorded during aggressive interactions. Modified sounds yielded little or no effect on the behavioural response they elicited in territorial males, suggesting a high tolerance for variations in pulse period and number of pulses. The biological function of sounds in M. zebra and the lack of responsiveness to our temporal modifications are discussed

Signals from the deep: Spatial and temporal acoustic occurrence of beaked whales off western Ireland - Fig 4

<p><b>Mean Cuvier’s beaked whale detections per recording day bubble plot (right) and with standard error bars (left) for stations 1 (SE = ±0.70), 2 (SE = ±0.59), 3 (SE = ±2.61), 4 (SE = ±4.48), 5 (SE = ±1.08), 6 (SE = ±1.38), 7 (SE = ±1.35), and 8 (SE = ±1.26) off western Ireland from May to Dec 2015 (stations 1–4) and Mar to Nov 2016 (stations 3 and 5–8).</b> Results of Kruskall-Wallis tests are given and results from Tukey-Kramer multiple comparisons tests are represented by coloured means (left) with different colours denoting a statistically significant difference. *Station 8 differs from 7, but not from 3, 5, and 6.</p