Amphibians
Barking Tree Frog
Dryophytes gratiosus · also called barking treefrog
On a humid summer night in the pinewoods of the Southeast, a sound like a distant pack of hounds drifts down from the treetops. It is not dogs. It is male barking tree frogs, the biggest tree frogs in the country, calling from high in the canopy.
Overview
Dryophytes gratiosus lives in the southeastern US coastal plain, in pine flatwoods and sandhills near seasonal ponds. At 5 to 7 cm it is the largest tree frog native to the United States, plump and warty-skinned, and it can shift colour between green, grey, and brown, usually keeping a scatter of dark round spots.
The two calls
From high in a tree the male gives a single hollow barking note; from the water while breeding he gives a lower, harsher, grating call. Many people who know one are surprised the other is the same frog.
It digs
In cold snaps and droughts the barking tree frog burrows backwards into loose sand or works into root channels and waits, sometimes for weeks — a habit that ties it to areas with deep sandy soil.
Status
Least Concern and locally common, but patchy, and a conservation concern at the northern and inland edges of its range where isolated populations have been drained or built over.
Barking Tree Frog: common questions
Why is it called a barking tree frog?
Because the male's call, given from high in a tree on warm humid nights outside the main breeding rush, is a single deep, hollow, resonant note that genuinely sounds like a dog barking in the distance. A group of males calling from the canopy can sound like a pack of far-off hounds. Confusingly, the same frog makes a completely different sound when it is actually breeding, and sitting in or beside the water, the male produces a lower, coarser, more doubled call. People who know the barking call from summer nights are often surprised the pond chorus is the same species.
How do I tell a barking tree frog from a green tree frog?
Size, shape, and skin texture. The barking tree frog is bigger and distinctly rounder and chunkier, and its skin is rough and granular rather than smooth. A green tree frog is slim and streamlined with smooth skin and usually a crisp white or cream stripe along each side. The barking tree frog often shows a scattering of dark round spots on its back, which the green tree frog lacks, and it can turn brown or grey, whereas the green tree frog stays some shade of green. Where they occur together they sometimes hybridise, which can muddy the field marks.
Do barking tree frogs make good pets?
They are kept by amphibian hobbyists and adapt reasonably well, but they have specific needs and, like all native amphibians, should only be obtained as captive-bred animals rather than collected from the wild. They need a tall, planted enclosure with climbing branches, a substrate they can burrow into, moderate humidity, and a diet of live insects. They are long-lived for a tree frog, often seven to ten years, and they are more prone to obesity than slimmer species, so feeding needs to be controlled. Handling should be minimal, as with any frog.
Where does the barking tree frog go in winter?
Underground. It is a coastal-plain species that experiences cold snaps and occasional freezes, and its response is to dig itself backwards into loose sandy soil, or to work into the root systems of shrubs and the burrows of other animals, and wait out the cold below the frost line. It does the same thing during summer droughts, when there is no moisture in the leaf litter and the ponds are dry. This burrowing habit, unusual among tree frogs, is one reason the species is tied to areas with deep sandy soils.