Name: | Description: | Size: | Format: | |
---|---|---|---|---|
1.79 MB | Adobe PDF |
Advisor(s)
Abstract(s)
Animals often vocalize during territorial challenges as acoustic signals may
indicate motivation and fighting ability and contribute to reduce aggressive
escalation. Here, we tested the function of agonistic sounds in territorial
defence in the painted goby. Pomatoschistus pictus, a small vocal marine
fish that defends nests during the breeding season. We first measured the
number of times a male approached, avoided, explored, entered and
exited two unattended nests associated with either conspecific agonistic
sounds or a control: silence or white noise. Acoustic stimuli were played
back when the male approached a nest. In a second experimental set, we
added visual stimuli, consisting of a conspecific male in a small confinement
aquarium near each nest. Even though we found no effect of the
visual stimuli, the sound playbacks induced similar effects in both experimental
conditions. In the sound vs. silence treatment, we found that
when males approached a nest, the playback of conspecific sounds usually
triggered avoidance. However, this behaviour did not last as in longer periods
males visited nests associated with agonistic sounds more often than
silent ones. When the control was white noise, we found no significant
effect of the playback treatment in male behaviour. Although we cannot
exclude the possibility that other sounds may dissuade nest occupation,
our results suggest that agonistic sounds act as territorial intrusion deterrents
but are insufficient to prevent nest intrusion on their own. Further
studies are needed to test the significance of sound production rate,
spectral content and temporal patterns to deter territorial intrusion in fish.
Description
Keywords
Citation
Ethology. 120, 53–63.