Some whales are taking jazz riffs to new depths.
For the first time, scientists have eavesdropped year-round on the songs of bowhead whales, the little-heard whales that roam the Arctic under the ice. They found that bowheads – the bigger, more blubbery cousins of the better known humpbacks – are more prolific and downright jazzier than other whales.
"Bowhead whales are the jazz singers of the Arctic. You don't know what they're going to do. They inject novelty," said Kate Stafford, an oceanographer at the University of Washington in Seattle.
Over three years a single underwater microphone captured 184 distinct bowhead whale songs, according to Professor Stafford's study in Wednesday's Biology Letters. That's remarkable because there are probably only a couple hundred males in an area between Greenland and Norway to make the songs, Stafford said.
Stafford and her colleagues couldn't track specific songs to individual whales to know for sure, but given the wide variety of songs they think each male has a different song, and that they likely change from season to season.
In contrast nearly all humpback males sing versions of the same song every winter, Stafford said. "Humpback whales are classical music singers. They make long elaborate songs but their songs are really ordered and almost predictable."
Until now, biologists would hear only snippets of bowhead songs in other Arctic areas. They have many recordings of humpback songs because there are more humpbacks and they travel much further south.
Scientists think only male bowheads sing and that they improvise to attract females with the best rendition of songs. The whales reminded Stafford of Miles Davis on his 1970 album in which he rejected traditional jazz for a rock-inspired improvisational style. Though she admitted bowhead music isn't for everyone.
"I find the songs to be quite beautiful, but some people compare them to fingernails on a chalkboard," Stafford said. "They're scream-y. They're yell-y and they're quite funny."
Bowheads – which can live to be 200 years old and are almost 60 feet long – start with very high notes, modulate their tune quite a bit, and at times make two completely different sounds at the same time.
"We don't know how they do that," Stafford said. Humans can't, but some birds can.
Syracuse University biology professor Susan Parks, who wasn't part of the study, praised the research as "a huge step forward" in learning about bowhead songs, showing surprising novelty and variety.
"The diversity of signal types uncovered by this study suggests that something very different is going on with bowhead whale song," Professor Parks wrote in an email.
One of Stafford's favorites makes repeated riffs of "woo-woo-woo" but with differing modulations. She'll often just turn the songs on her cell phone and bliss out.
"These guys are great mimics. They can imitate ice," Stafford said. "They make the nuttiest songs."
This article was reported by The Associated Press.