Which Birds Hold the Title of the World’s Loudest?

Scientists have finally cracked why some birds sound like tiny jets while others whisper.

1. Researchers recorded 123 species across 39 families, measuring the sound pressure at one metre using calibrated gear during field trips from late 2018 to early 2025 in Massachusetts and Brazil.
2. The data revealed a huge spread: a hummingbird barely reached 64 dB, whereas the bare‑throated bellbird hit a staggering 122.4 dB, with the white bellbird and red‑legged seriema also topping 120 dB.
3. Analysis showed two key drivers—body size and beak‑opening width. Bigger birds can pump more air, and a wider gape lets the sound escape more efficiently, boosting volume even after accounting for size.

In short, size and beak shape explain why the bellbirds and seriema roar louder than most feathered friends.