Predicting the cuescape from the reef soundscape and its role in larval fish settlement

The combined acoustic behavior of soniferous organisms living on benthic habitats from coral to oyster reefs produces habitat-specific soundscapes. These soundscapes are predicted to have a role in the settlement behavior of fish and invertebrate larvae searching for a benthic habitat on which to settle at the conclusion of their pelagic phase. Given the frequency-specific sound detection abilities of these organisms, only a portion of the soundscape will have the frequency and amplitude characteristics to serve as potential navigational and habitat selection cues. We recorded the soundscapes of four coral reefs in Caribbean Panama for six weeks and predicted the sounds most likely to be used as cues by larval fishes by using knowledge of their hearing sensitivity. Next we used an individual-based model to test the relationship between the temporal characteristics of the acoustic cues and settlement success. To do this we created cue time-series that represented the temporal variability observed at the four reef sites. We found that even short range, temporally variable cues produced at a low rate improved settlement success, suggesting these cues may improve the probability of survival under a broader range of conditions than has been typically considered.