This project aims to better understand Hawaiian monk seal underwater acoustic communication and assess the impacts of anthropogenic noise on their behavior and vocal activity.

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Background Information


Adult male seals of aquatically mating species produce underwater vocalizations during the breeding season when male-male competition for estrous females or territories is the highest. For the endangered Hawaiian monk seal (Neomonachus schauinslandi), with only 1,400 seals remaining, little is known about their underwater acoustic communication. Recreational divers have video evidence of Hawaiian monk seals vocalizing under water, yet descriptions of the vocal behavior of free-ranging monk seals do not exist in the scientific literature. By first gaining a basic understanding of Hawaiian monk seal vocal behavior, we can then evaluate the impacts of anthropogenic noise pollution on their communication system. Ultimately, this research aims to inform conservation and management decisions to better protect this endangered seal species. 



The aims of this project are to:

  • describe the acoustic properties of underwater calls produced by Hawaiian monk seals;

  • characterize the temporal patterns of these vocalizations (time of day and year);

  • identify the potential function of these vocalizations (predator avoidance, competition, mating);

  • create and test the accuracy of an automated call detector (enhance the efficiency of passive acoustic data analyses);

  • assess the potential impact of man-made underwater sound on the behavior and communication of this species.

research team

Lars Bejder - MMRP

Kirby Parnell - MMRP

Aude Pacini - MMRP

Charles Littnan - NOAA PIFSC

Michelle Barbieri - NOAA PIFSC

Colleen Reichmuth and Jillian Sills - Pinniped Lab UCSC

Isabelle Charrier - CNRS