« Calls from Wedel seal Create an almost unbelievable soundscape from another world under the ice »Paul Cziko, one of the authors of the appreciation study On their singing. Like other pinnipeds, these The mammals Semi-aquatic sailor with wing-shaped legs, The seals Waddell’s voices that are audible to humans. Until now, scientists had no doubt that they also produce Ultrasound. « It really feels like you’re in the middle of a space war in Smiling Star Wars Laser and all »Excites the researcher.

Between 2017 and 2018, a team of universities from Oregon (United States) and New Brunswick (Canada) dive into the frozen watersAntarctic Recording these vowels. Unexpectedly, their Hydrophone Sounds audible to humans have collected. But in listening, scientists realized: ultrasounds were seized on tape. ” Eventually we realized that the seals were using [ces appels ultrasonores] regularly Says co-writer Lisa Munger.

He counted to nine. new Ultrasonic tone Up to 50 kHz, although some hormones were over 200 kHz! For comparison, the human ear sounds between 20 and 20,000 Hertz – or 20 kHz. These ultrasonic calls now represent 17% of the known seal call repertoire. But an unknown relic: what are they for?

Nine vowels, two hypotheses

« You never know what you are going to get Eyes And ears in the ocean, especially Antarctica »Says Paul Cziko. This scientist speculates two possible causes of the ultrasound call. On one hand, they can be used for ” Stand out from low frequency noise like switching to a separate channel for communication “. On the other hand, they can allowEcholocitiesSay that one Sonar Organic is used to navigate when visibility is limited. During’cold For example, Antarctica, which seals Weddell in the dark for several months.

To uncover this mystery, researchers are planning large recordings. ” How do seals use these sounds? Lisa asks Munger, We need to record more locations to see correlations with behavior ».