Figure 1.

Experimental arena and acoustic conditions during trials. (a) Acoustic choice chamber (measurements in centimetres). (b) Comparison of audiogram for Amphiprion ephippium (17–20 days post-hatching) with measurements of reef noise playback within the chamber. Shaded area indicates predicted audible component of sound near to the speaker. Mean sound levels within the chamber without playback are also shown; maximum s.e. between CO₂-conditions was 1.2 dB (mean 0.6 dB) so error bars are not shown (black, 17–20 days post-hatching audiogram; red, near end of chamber; green, centre of chamber; yellow, far end of chamber; blue, no sound control).