Fig. 9

Hourly acoustic transmitter detections from all transmitter nodes at acoustic tag range-test Station 4, located within a narrow inshore passage. The data are plotted in raw form over the full deployment period (a); for a selected 10-day period following subtraction of the diurnal cycle (b); and over the full deployment period after being smoothed (c). In b, the red vertical lines indicate 8-h periods; in c, they indicate 15-day periods. In d, total daily transmitter detections from the most distant transmitter node (1200 m) are plotted in relation to predicted semilunar tidal amplitude at the study site