Pseudacris regilla

Adults: The color of their backs is highly variable: They are usually green or brown, but they can also be gray, tan, bronze, blackish, or reddish, often with irregular, dark spots or blotches. They have a dark stripe from their snout to their shoulder and can reach a length up to about 2 inches (5 cm).

Mature males: Males have a dark throat.

Breeding call: A loud, repeated “kreck-ek.”

Larvae: Tadpoles are brown or olive, often with spotting or mottling. Their eyes are set wide apart at the margin of the head, when viewed from above. They generally reach about 1.7 inches (44 mm) long.

Egg masses: Egg masses form in soft, loose clumps of around 10 to 80 eggs, and are attached to objects in shallow water.
 

This frog lives in many different habitats from southern British Columbia in Canada southward through the United States to southern Baja California, Mexico, and western Arizona, and east to Montana, Idaho, and Nevada. The species also occurs on the Channel Islands off Southern California. Desert populations in Southern California were probably introduced, as were some populations in Arizona. An introduced population occurs in the Queen Charlotte Islands, British Columbia, Canada, and on Revillagigedo Island in Alexander Archipelago, Alaska, where it was introduced in 1960 and is breeding. The elevational range extends from sea level to around 614 feet (3,540 m).

Under the taxonomic arrangement proposed by Recuero et al. (2006), the distribution of the species in the P. regilla complex presumably would be approximately as follows (Recuero et al. did not provide distributional details):

P. regilla: extreme southern Alaska (introduced), British Coumbia, Washington, western Oregon, and northern California.

P. sierra: central California, Nevada, eastern Oregon, Idaho, western Montana, and presumably extreme northwestern Utah (extirpated?).

P. hypochondriaca: Southern California, southern Nevada, southwestern Utah (extirpated?), and western Arizona south to southern Baja California.

The frogs described above occur in a wide variety of habitats, including grassland, chaparral, forest, and farmland. They live on land except during the breeding season.

 

Like many terrestrial amphibians, they are inactive during freezing weather and extreme drought. They may migrate several hundred meters (or yards) from land to water, where they breed. They generally breed in winter or spring (sometimes in summer). Females deposit eggs in the shallow water of marshes, lakes, ponds, ditches, reservoirs and slow-moving streams. Larvae metamorphose into tiny frogs within about 2-3 months. Pacific treefrogs generally do not breed until they are at least 2 years old. They often call, even when not breeding, and will even call when far away from their breeding sites.