Scientific American - Antarctic Seals Vocalize in Ultrasonic–but Not for the Usual Reason
Nearly one fifth of the underwater vocalizations produced by Antarctica’s Weddell seals occur at pitches above the limits of human hearing, according to a recent study
Author: Liz Allen
Published: February 4, 2021
Above the frozen ocean, Antarctica can be eerily quiet. Gusts of wind are often all one hears. Below, though, the Southern Ocean is a living soundscape dominated by Weddell seals. These pinnipeds typically emit high-pitched pings that sound like laser guns in a science-fiction movie. But that is not their entire repertoire. Research now reveals that a significant portion of their calls are at ultrasonic frequencies, high pitches well beyond the 20-kilohertz limit of most human hearing.
University of Oregon marine biologist Paul Cziko installed a lives-treaming audio and video system at Antarctica’s McMurdo Station in 2017, allowing scientists to listen in on the massive mammals’ underwater calls. Data from the setup yielded surprising results: The seals sometimes vocalized at extremely high, ultrasonic frequencies of more than 200 kilohertz, Cziko and his colleagues reported in the Journal of the Acoustical Society of America…