MEPS 605:173-193 (2018)  -  DOI: https://doi.org/10.3354/meps12737

ABSTRACT: The combined acoustic activity of soniferous organisms living in benthic habitats produces habitat-specific soundscapes, which are predicted to influence fish and invertebrate larval behavior during the settlement process. Not every sound will have the amplitude and frequency characteristics relative to hearing sensitivity to be used as an acoustic cue, thus the cuescape is a subset of the soundscape. These sounds vary through space and time, and little is known about how this variability could influence their role in settlement. We recorded the soundscapes of 4 coral reefs in Caribbean Panama for 6 wk and conservatively identified the sounds most likely to compose the cuescapes used by larval fishes. While these sites represented the variation in reef condition across the study area, we observed the same 4 dominant taxa groups emerge as the most likely producers of acoustic cues. These results were consistent across both time and space when compared to short-term recordings taken at these 4 reefs and at an additional 11 sites 2 yr prior. Next, we used an individual-based model to test the relationship between settlement success and the natural spatiotemporal variability we observed in these potential cues. Temporal variation in the sounds resulted in variation in settlement success; however, even short-range, intermittent cues improved the likelihood of settlement. Overall, we observed similar acoustic cuescapes across reefs that varied in condition, suggesting that cuescapes can be resilient to some forms of reef degradation by retaining sounds potentially useful to larval fishes for both navigation and habitat selection.

KEY WORDS: Coral reef · Soundscape · Larval fish · Larval settlement · Acoustics · Modeling · Cues · Fish behavior