For nearly forty years, a strange signal has been drifting through the North Pacific, making scientists scratch their heads. It comes in at 52 hertz, a pitch no known whale normally makes. The whale behind it, nicknamed “52 Blue”, quickly earned the title of the “loneliest whale” because no one has heard anything like it before.
The story started in December 1992, when Joe George, a technician at the Naval Air Station Whidbey Island, picked up the unusual signal using the Sound Surveillance System (SOSUS). The system was built to track submarines during the Cold War, but instead it revealed a call unlike any whale vocalization known. Most blue and fin whales sing between 10 and 40 hertz, far below 52, which made this discovery truly puzzling.
A Whale Singing In Its Own Voice
Few years ago, other scientists had already heard something similar. Researchers at the Woods Hole Oceanographic Institute detected the signal back in 1989 while surveying the North Pacific. Later, the Navy declassified the recordings so experts could study them. Based on a 2004 study, published in Deep-Sea Research:
“it is perhaps difficult to accept that if this was a whale, that there could have been only one of this kind in this large oceanic expanse, yet in spite of comprehensive, careful monitoring year-round, only one call with these characteristics has been found anywhere, and there has been only one source each season.”
What makes 52 Blue so unusual is the high frequency of its call. As explained by The Atavist, no whale species is known to vocalize at 52 hertz. Blue whales, fin whales, and humpbacks can hear it, but none of them sing at that pitch. Christopher Clark from Cornell University said that:
“The animal’s singing with a lot of the same features of a typical blue whale song. Blue whales, fin whales and humpback whales: all these whales can hear this guy, they’re not deaf. He’s just odd.”
Some think it could be a deaf blue whale, but its song still has the key patterns of a blue whale call, keeping the mystery alive.
A Hybrid Whale And Changing Oceans
Another explanation could be hybridization between blue and fin whales, sometimes called a “flue” whale. As reported by Grist, fin whales are much more numerous than blue whales; 37,000 near Iceland in 2024 compared to only 3,000 blue whales.Aimee Lang, a NOAA marine biologist, stated that:
“Three thousand is not a very high density of animals. So you can imagine if a female blue is looking for a mate and she can’t find a blue whale but there’s fin whales all over the place, she’ll choose one of them.”
As ocean conditions change, populations may become more isolated, creating more hybrids and possibly affecting how these marine mammals communicate.
What Whale Songs Reveal About The Deep Ocean
These deep-sea giants calls are incredibly loud. Blue whales can reach 188 decibels, which is louder than a jet engine, and their sounds can travel for thousands of miles underwater, carrying across entire ocean basins. The Atavist noted that these powerful vocalizations help these marine predators navigate, hunt, and communicate with one another over vast distances.
Remarkably, 52 Blue’s song has been going strong for nearly four decades, showing an almost tireless effort to make contact with the world around it. Scientists are beginning to decode the hidden patterns within cetacean songs, revealing clues about their complex communication systems.
