News Finding: The authors of the dolphin study raised similar concerns.
Paper Finding: Increases in ship noise, both within and below the dolphins' call bandwidth, resulted in higher dolphin whistle frequencies and a reduction in whistle contour complexity, an acoustic feature associated with individual identification.
News Context: The team suggests that more research would help determine if these sounds increased the stress levels of the affected humpbacks. The authors of the dolphin study raised similar concerns. "These whistles are really important," Bailey said in the statement.
Paper Context: Elevated ambient noise levels were mainly caused by ship noise. Increases in ship noise, both within and below the dolphins' call bandwidth, resulted in higher dolphin whistle frequencies and a reduction in whistle contour complexity, an acoustic feature associated with individual identification. Consequently, the noiseinduced simplification of dolphin whistles may reduce the information content in these acoustic signals and decrease effective communication, parent -offspring proximity or group cohesion.