Acoustic communication in the painted goby Pomatoschistus pictus: temperature dependence of male courtship sounds and their role in female mate choice

• Autor(a) principal: Vicente, Joana Rodrigues
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/7231
• topic: Biologia marinha; Teleósteos; Reprodução; Temperatura; Comunicação

Pomatoschistus pictus is a small vocal marine goby with paternal care inhabiting sandy or gravel substrates. Territorial breeding males court females with vocalizations (drums) and visual displays, from January to May, at various water temperatures. Males in better condition (larger lipid reserves) exhibit higher acoustic activity. However, it is unknown if females’ mate choice is based on males’ acoustic activity and how the latter is affected by temperature. Fish are ectotherms and therefore muscle contraction kinetics is temperature dependent which might influence sound production. We tested mate choice based on acoustic and visual signals with two playback experiments. Females were presented with high and a low drum rates broadcast from the lateral compartments of the aquarium. Acoustic playbacks were combined with the sight of two size-matched males confined in small glass aquaria. In the first experiment females did not have access to lateral compartments whereas in the second they could visit the confined males. Females did not show preference for sound rate in both experiments, suggesting that acoustic signals are part of a more complex multimodal communication and that females will only show active choice when they have access to males that can interact freely and exhibit their full repertoire possibly including chemical communication. We also evaluated the effect of temperature (14 – 22 ºC) on courtship drums of P.pictus. Our results show that drum duration and sound pulse period decreased with increasing temperature and that spectral peak frequency was negatively correlated with male size. Drum emission rate, sound amplitude and number of pulses in a drum were not affected by temperature. We discuss the implications of temperature-driven changes in acoustic parameters in fish acoustic communication, incorporating it in a climate change context.