Oregon Spotted Frog

Oregon Spotted Frog

Spotted Frog

Rana pretiosa

This page may contain affiliate links.
Read our disclosure and privacy policy here.

The Oregon Spotted Frog (Rana pretiosa) is a fascinating amphibian native to the Pacific Northwest region of North America. It is a medium-sized frog with a unique appearance characterized by its spotted skin, ranging in color from light to dark brown or green. They are often recognized for the distinct dark spots on their back and sides, which can be variable in shape and size. Adult frogs can reach a length of about 2.5 to 4 inches (6 to 10 centimeters). These frogs inhabit a variety of aquatic habitats, including wetlands, marshes, and slow-moving streams. They are known for their affinity to areas with dense vegetation and shallow water, where they can find shelter and food. The Oregon Spotted Frog has a gentle and secretive nature, often hiding among vegetation or submerged in water to avoid predators. They have a diverse diet that includes insects, spiders, worms, and other small invertebrates. Their lifecycle involves undergoing metamorphosis from tadpoles to adults, where they transition from aquatic to terrestrial life. The Oregon Spotted Frog is classified as a threatened species, facing population declines due to habitat loss, pollution, and predation by non-native species. They play an important role in their ecosystems by controlling insect populations and serving as a food source for other animals. While they do not possess toxins in their skin for defense, they rely on their camouflage and habitat preferences to avoid predators.

Oregon Spotted Frog

Common Name
Oregon Spotted Frog

Other Names

Spotted Frog

Latin Name

Rana pretiosa




These frogs have a rounded body shape with smooth skin. They have a brown or greenish-brown coloration with dark spots covering their back, sides, and legs. The spots can vary in size and shape, and some individuals may have fewer spots.


Adult Oregon Spotted Frogs typically measure between 2.5 to 3.5 inches (6 to 9 centimeters) in length. Females are usually larger than males.


They inhabit a range of aquatic habitats, including marshes, ponds, lakes, and slow-moving streams. They prefer areas with dense emergent vegetation, such as cattails and water lilies, which provide cover and food sources.


Oregon Spotted Frogs are primarily active during the night. They are excellent swimmers and are well-adapted to their aquatic habitat. They can be secretive and spend much of their time hiding among vegetation or submerged in water. They are known to bask in the sun during the day to regulate their body temperature.


These frogs are carnivorous and feed on a variety of invertebrates, including insects, spiders, worms, and small crustaceans. They will also opportunistically consume smaller frogs or tadpoles.


Oregon Spotted Frogs undergo a typical amphibian lifecycle, starting as eggs laid in shallow water. The eggs hatch into tadpoles, which undergo metamorphosis over several months, gradually developing legs and lungs. Eventually, they transform into juvenile frogs and then into adults. This transition from aquatic tadpoles to terrestrial adults is a critical phase in their lifecycle.


Oregon Spotted Frogs have a distinct vocalization that resembles a soft, low-pitched snore or a series of low grunts. Males use this vocalization during the breeding season to attract females and establish territory.

Defense Mechanisms

Rather than relying on toxins, Oregon Spotted Frogs rely on their camouflage and habitat preferences to avoid predators. They blend in with their surroundings, making it difficult for predators to spot them. When threatened, they may quickly jump into nearby water or hide in vegetation to escape predation.

Ecological Importance

Oregon Spotted Frogs play an essential role in their ecosystems. They help control populations of insects and other invertebrates, acting as a natural pest control. As prey for larger animals, they contribute to the food web and energy flow in wetland ecosystems.

Conservation Status

The Oregon Spotted Frog is listed as a threatened species. Loss and degradation of wetland habitats, water pollution, predation by non-native species, and the introduction of invasive plants have contributed to their declining population numbers.
Let's Go Avocado Team

There’s a lot to explore right where we are, in our own neighborhoods and backyards! Join us while we get off the couch and explore the everyday wonders of nature, science, space, engineering, art, and anything else we stumble upon during on our adventures.

More Posts: