Researchers Record Weddell Seals Chirping and Chattering Like Robots Below Ice for the First Time, They Have No Idea Why
Humans took one step further in understanding adorable seals in 2017 when they got privy to more of their sounds. Scientists went below Antarctica to record seals and uncovered them interacting with each other in what they termed as 'robotic' chatter, Live Science reported.
The researchers identified most of the seals in this recording as Wedell seals. Findings regarding their unique calls were published in The Journal of the Acoustical Society of America.
(Image Source: Getty Images/Photo by Mint Images/ Art Wolfe)
Researchers compared the new seal sounds to war calls in a very popular movie franchise. "The Weddell seals' calls create an almost unbelievable, otherworldly soundscape under the ice," Paul Cziko, a visiting professor at the University of Oregon and lead author of the study said. "It really sounds like you're in the middle of a space battle in 'Star Wars,' laser beams and all."
According to the study, these new sounds are inaudible to humans. Humans are capable of hearing sounds ranging from 20 to 20,000 hertz (or 20 kilohertz). These new calls were discovered to be 21 kHz or beyond. Researchers noted one high shrieked sound that reached 49.8 kHz. There were instances when the seals harmonized together, and that sound exceeded 200 kHz. Experts were able to capture these sounds by using a special hydrophone (an underwater microphone) installed in McMurdo Sound placed in the ocean.
The project helped humans associate nine new types of ultrasonic calls to seals. Experts are yet to figure out the meaning of these ultrasonic calls, or the situations that caused seals to use them. One speculation is that the ultrasonic sounds are a way for certain seals to stand out in conversations involving low-frequency sounds.
As per some experts, it is possible that the ultrasonic sounds were for the purpose of echolocation (sounds that aid marine beings in finding their way through dark places). Researchers are not completely sure of this claim, considering that seals have been observed to hunt and dive 1,900 feet (600 meters) below Antarctic waters.
The discovery delighted experts at that time because never before had they captured 'ultrasonic' sounds by seals. This finding gives an indication that other fin-footed mammals, like sea lions or walruses, could also have ultrasonic sounds in their repertoire and need to be analyzed.