Background noise was recorded on a monthly cycle with acoustic recording of 15 min in duration per each sampling stations with the stations (N = 12) monitored along the same day.
All recordings were made under similar sea state condition (1 or less than 1, Beaufort scale) to minimize the variation in shallow water ambient noise levels due to wind. A total of 118 SAN samples, equals to a total of 1770 min, were obtained over twelve acoustic stations with the mean of about 10 samples per observation station (SD ±2.3). The data was stored in
the WAV file format.