Some birds make beautiful chirps and tweets. Some sing sweetly. Some sound like they’re laughing, and some are talented enough that they can mimic other birds and even human speech. But the white bellbird is in a class of its own, blasting an obnoxious “song” so loud that it sounds almost digital. Now, researchers have measured just how ear-splitting that sound is – and crowned it the loudest bird call ever recorded.
The white bellbird lives in the mountains of the Amazon, in northern Brazil – and it’s not shy about making its presence known. The males of the species give off the telltale shrieks, which can be heard for miles, to attract females.
But the story doesn’t end once an interested lady bird comes knocking. Not only do the males save their loudest calls for when a female is checking them out, but they turn their head to aim the audible assault directly at them. In a way, it’s hard not to see it as a perfect metaphor for masculinity.
"While watching white bellbirds, we were lucky enough to see females join males on their display perches," says Jeff Podos, co-author of the study. "We would love to know why females willingly stay so close to males as they sing so loudly. Maybe they are trying to assess males up close, though at the risk of some damage to their hearing systems."
While the calls themselves are well-known – how could they not be? – the researchers say they’re the first to accurately measure how loud they can get. According to the study, the white bellbird can belt out a song at an intense 125.4 decibels.
For reference, that level of noise is in the realm of a rock show. It’s more thunderous than a thunderclap, cacophonous than a chainsaw, and even edges into the range of a jet engine during take-off. It’s far beyond the volume that begins to cause damage to human hearing – 85 dB – and is over the point that would be painful at close range.
That also makes it three times louder than the next loudest bird, the screaming piha. But the team notes a trade-off – the louder the song gets, the shorter its duration. That probably comes down to the birds’ respiratory system having a limit to its ability to control airflow to create sound.
That said, the bird is known to have pretty well-developed ab muscles and rib bones, helping it project to the back row.
The researchers plan to continue studying the bird to find out more about how and why its song is so loud – and just how the bellbirds can sing like that without deafening themselves or their prospective mates.
The research was published in the journal Current Biology.
Source: University of Massachusetts
