Color – Changeable from a color so dark that it is nearly black, to a flesh color. When light, the coloration may be bluish or ash grey, fawn color, or even salmon or red in tone. Iris golden or copper colored. There is a dark stripe which begins at the muzzle and extends through the eye and ear, and less conspicuously to the middle of the side of the body or beyond. This dark color is bordered below by a light band which extends to a point back of the arm. The immediate edge of the jaw is dark. There may be a pattern of dark lines or spots on the back, head, and legs. This pattern consists typically of the following:

1. Three longitudinal stripes (or series of spots). The middle one of the three occupies the midline of the back and may fork posteriorly. The two others extend backward and parallel to this, from the posterior angles of the eyes.
2. A transverse band between the eyes connected with the median stripe.
3. Crossbands, or more or less irregular lines of spots, on the hind legs. The underparts are a yellowish white. The throat of the male is a greenish yellow.

Measurements – size small, i.e length of 1 inch, slightly more or less. The Body relatively is long and slender. Length of the head is variable. The greatest length is presented by the Western and Northern forms, frogs from the South have a muzzle considerably drawn out, and those from the East are distinguished by relative shortness of the muzzle. The length of the legs is variable.

Structure – Skin of upper parts are finely tubercular; under parts granular. The head is narrow and pointed. Nostrils much nearer to the tip of the muzzle than to the eye. Muzzle extends beyond the line of the jaw. Ear is small, only ¼ to ½ the diameter of the eye. Eyes are widely separated. Long and slender toes are scarcely webbed. The disks on the toes and fingers are very small.

Range – This member of the Hylidae has the widest distribution of any member of its group in North America. It has been reported from every state, with the exception of those of Northern New England, and Arizona, Northern New York, Michigan, California, Oregon, and Washington.

Calls – In the Southern States the Swamp Tree frog is heard singing in Late January and early February. The chorus of the Swamp Tree frog proceeds from ditches, marshes, and pools, especially low lands. They sing throughout many of the days, and of course during the night, until Late April, when the breeding season is over. The chorus is not that penetrating, it is soft, relatively low pitched, and is said to have a soothing sound that swells and recedes “like the waves of the seashore”. The Chorus is loud though, so it sounds as if a big frog were producing it. The call is given by the male only; and the inflated throat-pouch is large.

Characteristics - The Swamp tree frog stays in the Marshes throughout the summer and fall. We may sometimes hear the isolated call from marshy land during the hottest part of the summer, but on the whole, the species is rather silent except during the breeding season. These frogs seek refuge in the water when they are disturbed, but are very poor swimmers and soon crawl back to shore out on some miniature log. They are seldom seen after the spring moths owing to their minute size, their protective coloration, and their silence. They feed upon flies, beetles, and various insects that frequent marshy places.

The Swamp Tree Frog is slender and delicate in appearance. It has great power to change its color between light and dark shades. Each Swamp frog has its own distinctive pattern of color – we can scarcely find two alike among several dozens caught in the same location. What’s more, the given patterns in a single specimen may be wholly absent at one time, faintly outlined in another and prominently marked a third, all within the space of an hour.

The eggs are laid in shallow water in March or April. They are in small bunches of from 5 to 20 eggs and are attached to twigs and grasses in the water. The tadpoles both at the time of hatching and later, are nearly black in color. By April 20th most of the tadpoles have already budded and are about ½ inch long, are black in color, and are finely dotted with gold. Between May 26 and June 12, the final transformation takes place. The front legs appear, the toes furnished with the small disks. Since the feet are slightly webbed, the young frogs are poor swimmers and are drowned unless they have the opportunity to leave the water.

These young frogs are extremely delicate and shy. They look like full grown tree frogs, except that they are only ½ an inch in length. They usually hide under convenient leaves, sticks, and stones in the marsh.