Sounds Recorded in the Presence of an Adult and Calf Bowhead Whale, 'Balaena Mysticetus'.

Low-frequency sounds were recorded on 23 May 1978 in the presence of an adult bowhead whale and accompanying calf, near Point Barrow, Alaska. The ice conditions at that time were changing. The ice pack was moving toward the shore-fast ice, with the imminent possibility of total lead closure. Under these conditions, sounds were detected 10 minutes before whales were sighted in the lead at an estimated distance of 400 to 500 m from our position. Of the 75 vocalizations recorded, 35 were of sufficient quality to be analyzed. These sounds were of two types, identified throughout this text as Type A, short duration sounds, and Type B, long duration sounds. Eighteen were Type A and ranged from 0.35 to 0.85 seconds in duration the fundamental frequency ranged from 50 Hz to 580 Hz. In three instances, a Type A sound was followed immediately by a Type B sound. Fifteen Type B sounds ranged fgrom 0.65 to 2.56 seconds in duration, with the fundamental frequency ranging from 100 Hz to 195 Hz.