Pacific Tree Frog Facts

Pacific tree frogs (Pseudacris regilla) are small frogs found throughout the West Coast of North America, including Mexico, California, Oregon, Washington and British Columbia. Male Pacific tree frogs emit the distinctive two-part or diphasic "rib-it" or "krek-ek"advertisement call, giving the second syllable a higher inflection. These calls are usually emitted in the evening and at night.

  1. Size

    • Adult Pacific tree frogs measure approximately 3/4 inch to 2 inches long from their snout to vent. Tadpoles grow up to almost 2 inches long.

    Appearance

    • Pacific tree frogs are usually green or brown, but can also appear tan, gray, reddish or cream. They can change their color from light to dark to adapt to environmental conditions. The underside of the frogs appears cream-colored. They have large heads and eyes, and smooth, moist skin. Pacific tree frogs also have round pads on the tips of their toes. Male frogs have dark, wrinkled throats. Tadpoles range from blackish to dark brown in color.

    Habitat

    • Pacific tree frogs thrive in a variety of habitats, including forests, pastures, woodlands, grasslands and desert streams. They typically reside among grasses and shrubs near water, but can also climb trees. Pacific tree frogs often hibernate in dense vegetation or mammal burrows to avoid extreme temperatures.

    Reproduction

    • Pacific tree frogs reproduce between November and July. Male frogs attract females by making advertisement calls. Pacific tree frogs breed aquatically, in locations including ponds, marshes, lakes, wetlands and slow streams. Reproduction occurs through external fertilization. Female Pacific tree frogs lay between 400 to 750 eggs, which hatch after two to three weeks.

    Diet

    • Pacific tree frogs consume a variety of invertebrates, including flying insects. They generally feed at night, except during breeding season, when the frogs also eat throughout the day. Pacific tree frogs utilize their long, sticky tongues to catch prey. Tadpoles consume bacteria, algae and protozoa.

    Fun Fact

    • The diphasic calls of the Baja California tree frog, which sound identical to those of the Pacific tree frog, were commonly used as nighttime sound effects in old Hollywood movies.