Some birds sing sophisticated and enchanting songs to court their mates. Male white bellbirds (Procnias albus), however, are not that artistic. Instead, they make up for their lack of musical talent with an in-your-face call. According to a recent study, their bird calls are the loudest ever recorded.
Although they’re the size of a dove, these birds emit a deafening call that’s three times louder than that of screaming pihas (the previous record holder for the loudest bird call) and even louder than the calls of howler monkeys and bison.
Jeff Podos, a biologist at the University of Massachusetts Amherst, used cutting edge sound recorders, sound-level meters, and high-speed cameras to measure the amplitude of the bellbird’s calls with extremely high temporal precision.
“This allows us to see how amplitude changes and peaks within individual singing events,” he said in a statement.
These measurements showed that the bellbird emits calls that are louder than any musical instrument — an impressive feat for a creature that only weighs a quarter of a kilogram (half a pound).
The white bellbird’s call, by the way, sounds like a cross between a digital sound alarm and a really bad synthesizer. Judge for yourself from the recording below.
“We were lucky enough to see females join males on their display perches. In these cases, we saw that the males sing only their loudest songs. Not only that, they swivel dramatically during these songs, so as to blast the song’s final note directly at the females. We would love to know why females willingly stay so close to males as they sing so loudly,” he says. “Maybe they are trying to assess males up close, though at the risk of some damage to their hearing systems.”
In order to understand how such small animals are able to emit loud sounds, the researchers measured the bird’s breathing muscles, head and beak size, and its throat shape. Although this kind of analysis is still in its infancy, the authors found that there’s an inherent trade-off between size and loudness — as the birds get louder, they get smaller. They hypothesize that this may be due to the bird’s respiratory system, which has a finite ability to control airflow.
Previously, Podos and colleagues found that bellbirds have unusually well-developed abdominal muscles and ribs. In the future, the researchers would like to further study “the physical and anatomical structures and behaviors that allow bellbirds to produce such loud sounds and to endure them without hearing damage.”
The findings were reported in the journal Current Biology.
