Researchers have identified the bare-throated bellbird and the red-legged seriema as two new contenders for the world’s loudest bird. Both species produce calls exceeding 120 decibels, matching the volume of a jackhammer. The findings, published this week in the journal Evolution, provide unprecedented amplitude measurements for 123 different bird species.
New Loudest Bird Contenders Measured via Laser
Biologist Jeff Podos of the University of Massachusetts Amherst and his former graduate student João C.T. Menezes have expanded the record books for avian vocal power. Their research identifies the bare-throated bellbird and the red-legged seriema as birds capable of hitting volumes above 120 decibels. At roughly 125 decibels, the white bellbird’s call is louder than standing next to a revving chainsaw, a claim confirmed by Guinness World Records.
Measuring bird calls in the wild has historically been a challenge because vocal amplitude depends heavily on the distance between the source and the microphone. To overcome this, the team used laser rangefinders—tools typically utilized by golfers—to calculate exact distances. They then paired these measurements with readings from industrial-grade sound level meters. According to Podos, the researchers had to get their boots on the ground to conduct this work, which involved taking measurements around Amherst and across Brazil. The project successfully captured amplitude data for 123 species, 113 of which had never before had their volume catalogued.
Data Contradicts Theories on Why Birds Evolve Loudness
These birds also feature bulky muscles that potentially allow for greater air compression.
Despite these physical correlations, the team found little evidence to support common theories regarding why birds evolve such extreme loudness. They had hypothesized that louder calls might be linked to weak flight capabilities, dense forest habitats, or polygamous mating systems. However, the data provided contradictory evidence, as the top three birds serve as perfect counterexamples to those specific ecological factors.
For instance, while the bare-throated bellbird lives in dense forests and is highly polygamous, the red-legged seriema inhabits open pastures and maintains long-term monogamous pair bonds. Menezes noted that since amplitude is known for so few species, researchers could potentially find new examples in diverse locations, from his window in São Paulo to a backyard in Massachusetts.
Researchers Plan to Uncover How Birds Produce Loud Signals
Menezes and Podos expressed that the process of observing and measuring these animals in the field is a fundamental part of the scientific experience. For Menezes, who has been a bird watcher since childhood, the study provided an additional layer to his hobby. The team plans to continue their work to uncover what enables birds to produce the loudest acoustic signals among all terrestrial fauna.