8/3/2023 0 Comments Blue whale song![]() And that shift is consistent around the world-even though the local anthems are not. (If it seems strange that their songs are so loud yet imperceptible to us, consider that our ears barely register 100-decibel dog whistles.) But now their voices have inexplicably shifted from bass to basso profundo, Elvis to Barry White. Blue whales are not only the world’s largest animals, over 75 feet long and weighing around 300,000 pounds they are the world’s loudest, whose 180-decibel songs-as loud as a jet plane-can be heard 500 miles away by properly-attuned ears. Together, they had stumbled onto what would become one of the biggest unsolved riddles of blue whale research for decades to come. BASSO PROFUNDO: For the past 20 years, whale researchers have struggled to understand why the songs of blue whales keep steadily sinking to lower registers. Then he and McDonald, who runs a private ocean acoustics consultancy, listened to other populations of blue whales in the Antarctic and the Central Pacific, each of which sings a different song. “You could really see, ‘oh my God, this thing has shifted a lot,’ ” says Hildebrand, who heads the whale acoustics lab at Scripps Institution of Oceanography in San Diego. The frequencies had declined by 30 percent over 40 years. Eventually they got their hands on some of the earliest known recordings, created by the Navy in the 1960s and stored on analog cassettes. To figure out if it was just an anomaly or something more, Hildebrand and McDonald embarked on a quest to find some really old songs. ![]() Northeast Pacific blue whale call, courtesy of NOAA Pacific Marine Environmental Laboratory (PMEL) But according to Hildebrand and McDonald’s instruments, the tonal frequencies of the songs had been sinking to even greater depths for three straight years. ![]() If you want to listen to one, to actually hear its ethereal patterns of wobbly pulses and haunting moans, you have to speed it up by at least two-fold. But their algorithm kept crashing.īlue whale songs fall below the range of human hearing. John Hildebrand and Mark McDonald were trying to build a system that would allow them to automatically detect blue whale songs off the coast of southern California. In 2001, a pair of physicists turned whale researchers noticed something puzzling in their data.
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