Mate preference in the painted goby: the influence of visual and acoustic courtship signals

Abstract

SUMMARYWe tested the hypothesis that females of a small vocal marine fish with exclusive paternal care, the painted goby, prefer high parental-quality mates such as large or high-condition males. We tested the effect of male body size and male visual and acoustic courtship behaviour (playback experiments) on female mating preferences by measuring time spent near one of a two-choice stimuli. Females did not show preference for male size but preferred males that showed higher levels of courtship, a trait known to advertise condition (fat reserves). Also, time spent near the preferred male depended on male courtship effort. Playback experiments showed that when sound was combined with visual stimuli (a male confined in a small aquarium placed near each speaker), females spent more time near the male associated with courtship sound than with the control male (associated with white noise or silence). Although male visual courtship effort also affected female preference in the pre-playback period, this effect decreased during playback and disappeared in the post-playback period. Courtship sound stimuli alone did not elicit female preference in relation to a control. Taken together, the results suggest that visual and mainly acoustic courtship displays are subject to mate preference and may advertise parental quality in this species. Our results indicate that visual and acoustic signals interplay in a complex fashion and highlight the need to examine how different sensory modalities affect mating preferences in fish and other vertebrates.

Fish Sounds and Mate Choice

“…More recently, Amorim et al (2013a) have found that fatigue (measured as the ratio between the average pulse period observed at the end and the beginning of the mating drum) was very stereotyped in the painted goby (P. pictus) and that it was a good predictor of male size, explaining 45 % of the variability found in this male feature. This increase in resistance to fatigue in larger animals was, however, not found in the congeneric sand goby (P. minutus) that make similar drums but with a higher pulse repetition rate than P. pictus (Amorim et al 2013b), suggesting interspecific differences in physiological constraints in sound production.…”

“…Painted gobies gravid females that were exposed to a dichotomous choice of courtship sounds versus a control (silence or white noise) did not show a preference for conspecific sounds (Amorim et al 2013b). However, when courtship sound playback was associated with visual access (but not chemical) to a conspecific male, females preferred to affiliate with the male associated with sound than with the control male.…”

“…However, when courtship sound playback was associated with visual access (but not chemical) to a conspecific male, females preferred to affiliate with the male associated with sound than with the control male. Notably, female preference was influenced by male visual courtship effort before the start of sound playback (preplayback period) but this effect decreased during playback and disappeared after sounds ceased (postplayback period; Amorim et al 2013b). These results indicate that courtship sound alone does not seem to affect mate preference in this goby species (as in Bathygobius spp.…”

“…As territorial males were removed prior to playbacks, females performed their choices based solely on acoustic information. In these experiments bicolor damselfish females had a choice between the sounds of two males that differed by 4 mm (8 % of standard length) and by 70 Hz (710 vs. 780 Hz) in Amorim et al (2013b) to assess the role of courtship sounds in mate choice in Pomatoschistus pictus (a). Female preference for confined males associated with sound playback versus control males (associated with silence or white noise) was measured by the percentage of time the female spent in the sound 'response zone' (RZ) in relation to the total time spent in the two RZs.…”

“…Difficulties include the inexistence of commercial underwater loudspeakers that can reproduce fish low-frequency pulsed sounds accurately (Fonseca and Maia Alves 2012), hindering the success of playback experiments in most fish species. Fish sounds are usually accompanied by signals of other sensory modalities, such as conspicuous visual displays, making the role of acoustic signals difficult to establish (Amorim et al 2013b). Also, the lack of adequate motivation by subject fish, which is difficult to evaluate, may limit the response to experimental protocols (Myrberg et al 1986).…”