The Loudest Birds on Record: Bare-Throated Bellbird and Red-Legged Seriema

On September 29, 2026, researchers from the University of Massachusetts Amherst published a peer-reviewed article in *Evolution* that measured vocal amplitude in 123 bird species across South America. The study found that the bare-throated bellbird and the red-legged seriema produce the highest sound levels ever recorded for avians.

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To capture authentic calls, the team—led by evolutionary biologist João C.T. Menezes and acoustic ecologist Jeff Podos—used laser-rangefinders and portable sound meters while observing birds in their natural habitats. The approach allowed precise decibel readings that accounted for distance from the source. Of the 123 species surveyed, 113 had never before been measured for vocal amplitude, expanding the scientific database dramatically.

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The bare-throated bellbird reaches roughly 131 decibels, and the red-legged seriema exceeds 120 decibels—levels comparable to a jet taking off or a chainsaw in operation. Researchers linked this extreme loudness to anatomical features: larger body size, wider beak openings, and more robust chest muscles that enable greater air compression. While the data confirm “the how” of the birds’ powerful songs, the study did not uncover a clear ecological or evolutionary purpose for such volume.

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Menezes noted that the research now clarifies several physical mechanisms behind extreme vocal output, yet the underlying selective advantages remain uncertain. Podos emphasized that field-based measurements are essential, stating that laboratory or internet-derived data cannot substitute for direct observation of birds in the wild. Both scientists expressed intent to return to the field to test emerging hypotheses about the role of loudness in avian ecology.

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• “They can even exceed elephants and lions and wolves and bison,” — João Menezes — João Menezes, evolutionary biologist and lead author.

New York Times