Amphibians
Bird-Voiced Treefrog
Hyla avivoca · also called bird-voiced tree frog
Stand beside a southeastern swamp after dark and a whistling call drifts down from somewhere in the trees, prompting an instinctive search of the canopy for a bird that was never actually there. The real source is a small, mottled treefrog calling from vegetation near the water, its voice good enough to fool the search every time.
Overview
The bird-voiced treefrog, Hyla avivoca, is a small, camouflaged amphibian native to wooded swamp and river floodplain habitat across the southeastern United States. Its distinctly bird-like whistling call gives the species its common name.
A voice that outperforms its camouflage
While the bird-voiced treefrog’s mottled body blends effectively into bark and swamp vegetation, its call does the opposite, carrying clearly enough to be heard readily, just consistently misattributed to the wrong kind of animal entirely.
Status
Least Concern — widespread and stable across suitable wooded swamp and floodplain habitat throughout the southeastern United States.
Bird-Voiced Treefrog: common questions
Why is it called the bird-voiced treefrog?
A male bird-voiced treefrog produces a distinctive whistling call that closely resembles certain bird vocalisations, a resemblance close enough that the species regularly fools human listeners into scanning nearby trees for a bird rather than recognising the sound as coming from a well-camouflaged frog calling from swamp vegetation.
Where does the bird-voiced treefrog actually live?
The bird-voiced treefrog is native to wooded swamp and river floodplain habitat across parts of the southeastern United States, generally favouring areas with mature trees bordering slow-moving or standing water, where it breeds and forages primarily after dark.
How can you tell a bird-voiced treefrog from similar treefrog species?
Beyond its distinctive bird-like call, a bird-voiced treefrog typically has pale yellow or greenish colouration on the underside of its hind legs, a feature that, combined with its mottled grey-green camouflage pattern and specific wooded swamp habitat, can help distinguish it from some similarly patterned treefrog relatives.
Is the bird-voiced treefrog active during the day?
No, the bird-voiced treefrog is primarily nocturnal, remaining hidden and largely inactive during daylight hours and becoming active to call and forage only after dark, a pattern that helps the species avoid daytime predators and the heat typical of its southeastern United States wetland habitat.