In the dense Serra do Mar mountains of Brazil, the bare-throated bellbird produces one of the most powerful bird calls ever recorded, according to a recent scientific study. Measuring no larger than a dove, the bellbird’s call is remarkably loud—louder than common industrial noises such as jackhammers and chainsaws, and surpassing the trumpet of an elephant.

The study, published in the journal Evolution and led by evolutionary biologist João Menezes, highlights the bellbird’s call as unmatched in amplitude, a key factor in sound intensity. Amplitude, which reflects the height of a sound wave, is critical in determining how far a sound can travel and how loud it appears to the listener.

Alongside the bare-throated bellbird, the researchers identified another Brazilian species, the red-legged seriema, as equally capable of generating some of the loudest birdsongs. These two species now join a previously documented bellbird species at the pinnacle of the volume spectrum among birds.

The investigation also provided insights into the specialized anatomical features that enable these birds to produce such forceful sounds, helping address longstanding questions about the mechanics of birdsong production. Unlike prior studies that often focused mainly on frequency and pitch, this research concentrated on amplitude, which had remained difficult to measure accurately in wild birds.

Researchers face challenges in quantifying bird call amplitudes because it requires isolating an individual bird’s song from a chorus of others and precisely determining the distance from the recording equipment. Due to these complexities, even well-studied species such as the Canada goose have not had their birdsong amplitude thoroughly measured until now.

This study marks a significant advance in understanding the physical and biological factors that govern the loudness of birdsong, revealing the extraordinary vocal abilities of certain avian species in Brazil’s tropical forests.