A male tree frog can produce a call louder than 110 decibels, matching the volume of a chainsaw or a rock concert.

The North American bullfrog and various tree frog species, such as the Barking Tree Frog (Hyla gratiosa), are capable of producing sounds that exceed 110 decibels at a distance of 50 centimeters. This volume is comparable to a power saw or a jet takeoff from 300 meters away. The primary mechanism is the vocal sac, which acts as a resonant chamber that increases the efficiency of sound radiation into the air.Research published in the journal 'Science' and studies by herpetologists at institutions like the University of Texas have shown that calling is the most energetically expensive activity a frog performs. A male frog can expend up to 25 times more oxygen during a calling bout than it does at rest. This metabolic demand is so high that many males can only sustain the activity for a few nights before needing to forage and recover.To prevent self-inflicted hearing damage, some frogs have evolved a unique lung-to-ear pathway. A 2021 study in 'Current Biology' found that when a frog inflates its lungs, it reduces the sensitivity of its eardrums to its own frequency range. This internal pressure equalization allows them to hear rivals and predators while muting the overwhelming volume of their own calls.In dense choruses, the collective sound of a colony can reach 120 decibels, which is the human threshold for pain. This acoustic competition is a form of sexual selection where females often choose males based on the duration, frequency, and volume of their calls. These traits serve as honest signals of the male's physical health and energy reserves.