Male damselfish perform a courtship behavior called the signal jump, in which they rise in a water column and then rapidly swim back downward. The signal jump involves large amounts of rapid swimming, and females choose mates based on the vigor with which males do so. Females determine the male courtship rates using sounds that are produced during signal jumps. As the male damselfish swims down the water column, it creates a pulsed sound. Male courtship varies in the number and rates of those pulses.