The number of clicks/minute as a function of elapsed time in hours (thick line).

<p>(A) and (B) show data from the last 5-day session each dolphin participated in and (C) is data from the 15-day session. Model predictions are plotted as thin lines with their respective parameters. Shaded areas represent night while unshaded areas represent day. Both dolphins have a diel pattern with a period (λ) of about 24 hrs and a negative slope (b) for their last 5-day session. The model was not appropriate for the 15-day session.