Influence of fish size (SL) on acoustic variables in 14 clownfish species. Correlation of (A) pulse duration and (B) dominant frequency against SL. Note that data related to dominant frequency were ln-transformed because they were exponentially related to fish size. Fishes ranged from 37 to 110 mm (n = 43). The significance level was determined at p < 0.05. Results are expressed as mean values of 50 recorded pulses for each individual.