Summary
Two captive harbor porpoises (Phocoena phocoena) were exposed to three sound types (frequency from 100 kHz to 140 kHz, 200 ms long, and presented once per 4 s). Each session consisted of a 10 min period per sound, a 5 min period of sound, and a 10 min period after the sound. Behavior was recorded on video and with dataloggers. Animals reacted most to the initial presentations of sound, but the reactions diminished rapidly in repeated sessions.