The strange song was first heard in 1989, by a classified array of sensors—hydrophones spread across the floor of the Puget Sound by the Navy. They were originally supposed to pick up the rumble of Soviet subs, but when the array was partially declassified, researchers began to use it to listen to the noises of the ocean, a place that is anything but silent. On December 7, 1992, a technician noted a noise that appeared to be the song of a whale. But, strangely, it was coming in at a frequency of 52 hertz. Leslie Jamison writes in "52 Blue" from the Atavist (excerpted by Slate):
For a blue whale, which is what this one seemed to be, a frequency of 52 hertz was basically off the charts. Blue whales usually come in somewhere between 15 and 20—on the periphery of what the human ear can hear, an almost imperceptible rumble. But here it was, right in front of them, the audio signature of a creature moving through Pacific waters with a singularly high-pitched song.
The odd pitch attracted the attention of researchers, media and the public—all of whom almost immediately latched on to the story of this whale, dubbed the 52 hertz whale or 52 blue. Andrew Revkin from the New York Times spoke to Kate Stafford, a researcher at the National Marine Mammal Laboratory in Seattle who was listening to the whale’s sound:
"The fact that this individual has been capable of existing in that harsh environment for at least these 12 years indicates there is nothing wrong with it," she said. But she agreed that there was something poignant about the finding.
"He's saying, 'Hey I'm out here,' " she said. "Well, nobody is phoning home."
Here’s 52’s sound, sped up to be more audible:
Many regard this whale as the loneliest in the world. There’s even a Kickstarter campaign built around finding the Lonely Whale. (Though we have many recordings, no one has yet found the creature. Sound carries far in the ocean.)
Bill Watkins, a marine mammal researcher at the Woods Hole Oceanographic Institution poured over 12 years worth of recordings and concluded that the whale was certainly unique. But some researchers question the narrative that the whale is lonely.
For BBC Nature, Chris Baranuik writes:
One critic is Christopher Willes Clark of Cornell University in Ithaca, New York. He made recordings of the 52Hz whale in 1993 and says it's not quite as anomalous as it might seem.
Many types of idiosyncratic whale calls have been detected, and some studies suggest that groups of whales living in particular regions have dialects. When you consider that, the 52Hz whale is "not completely mind-bogglingly unique," he says.
Furthermore, Clark and others reject the idea held by some that the 52Hz whale cannot be heard or understood by "normal" blue whales that make lower-frequency calls. "The animal's singing with a lot of the same features of a typical blue whale song," he says. "Blue whales, fin whales and humpback whales: all these whales can hear this guy, they're not deaf. He's just odd."
Though many refer to the whale as "he," we still don’t know the whale’s gender or even species. The mystery whale may be a hybrid between two different species, though the pattern of behavior seems to indicate a blue. "It had the exact same seasonality as blue whales and if you look at the migratory patterns that Bill and his colleagues found, it's the same thing," Kate Stafford told BBC. "So I feel pretty confident that at least part of this animal is a blue whale."
The song may even be sung by more than one whale. In 2010, Baranuik reports, sensor off the coast of California picked up calls that appear to follow the pattern found by Wilkins but showed up on widely separated sensors. John Hildebrand of the Scripps Institution of Oceanography notes that this means multiple animals could be singing.
Only a concentrated search will identify the singer of the 52 hertz song—whether it is one lonely individual or a group of hybrids. In the meantime, the rest of us will wait and listen.