Sound Matters: Experimental Considerations for Acoustic Studies of Coral Larvae
摘要
Larvae of stony corals have recently been shown to settle in response to acoustic cues from reef soundscapes. This discovery has prompted interest in investigating coral responses to sound and developing tools to use broadcasted sound for coral restoration. However, acoustic features of natural reef soundscapes are spatiotemporally variable. Sensitivity of coral larvae to this wide array of potential acoustic stimuli remains unstudied. This chapter presents data from playback trials using the Indo-Pacific coral Pocillopora damicornis, in which larvae were exposed to four acoustic treatments: white noise, Caribbean reef sounds, Pacific reef sounds, and a “no-sound” control. When larvae were exposed to both sound and an added chemical stimulus (powdered crustose coralline algae), mean settlement in the white noise and Caribbean reef tanks was 1.6–1.9 times higher than Pacific reef or control treatments. However, statistical modeling showed evidence of strong tank and position-driven effects, with higher settlement occurring in tanks where low-frequency (<1000 Hz) root-mean-square particle acceleration levels were over 105 dB re μm/s2. These results provide insight into the acoustic settlement preferences of coral larvae while highlighting practical challenges associated with replicating marine soundscapes in small tanks.