The world's loudest bird
With a sound level comparable to a jackhammer, White bellbird males scream their love songs right into females' ears.
As Jeffrey Podos and Mario Cohn-Haft fought their way through the rainforest of the Brazilian Amazon in late 2018, they did not know that their expedition would lead to a new Guinness World Record. Carrying microphones through the densely vegetated forest, they were about to record what is today known as the bird with the loudest call in the world—the White bellbird.
About 21 years earlier, ornithologist Erwin Nemeth and his research team had recorded another bird of the Amazon rainforest, the Screaming piha (Lipaugus vociferans). They reported that this bird reaches sound levels of more than 110 dB(A) at a distance of one meter—a level of loudness that falls between the thresholds of discomfort and pain in humans. Since then, the Screaming piha had been considered the loudest bird in the world.
Well, no one had measured the White bellbird yet!
During their expeditions in 2018 and 2019, Podos and colleagues recorded both the Screaming piha and the White bellbird, and they found that the White bellbird was more than 9 dB louder than the previous record holder1! With calls reaching up to 125 dB at a distance of one meter, the White bellbird was officially the loudest bird ever recorded. Its peak sound level is comparable to that of a jackhammer or an ambulance and is considered painful and dangerous for the human ear.
Producing such extremely loud calls pushes the birds to their physical limits. Still, sexual selection may favor the evolution of this kind of extravagant and energy-demanding courtship behavior. The researchers observed that the louder a White bellbird calls, the shorter its song becomes. The birds reach their respiratory limits sooner when producing louder sounds, which indicates that they already perform at the limits of what is physically possible.
During courtship, however, nothing can stop them, and the males scream their love songs right into the females’ ears. If a female joins a male on his display perch, he even produces the louder of his two song types—despite the close proximity of his potential mate.
The researchers concluded that females need to find a balance between their interest in assessing males at close range and their need to protect themselves from hearing damage.
What I wonder, however, is how (or whether) the males themselves protect their hearing from their own screaming!
Have a wonderful rest of the week! All the best,
Great post, Maja! When we were in Costa Rica, we got to see Three-wattled Bellbirds. A female perched near a male and when he turned toward her and opened his mouth to “sing,” she leaned away and clenched her eyes shut!
Humans and other mammals have an automatic protection against loud sounds, especially from our own voice which would otherwise be well over the pain threshold internally. When we vocalize, the brain automatically pulls a little muscle (tensor tympani) that restricts the movement of the eardrum. Another muscle restricts the movement of the stapes where it enters the cochlea. Without looking it up, I'm pretty sure birds are built the same way.