Oregon is home to ten unique species of frogs, all indigenous to the state; however, one of the types of frogs in Oregon, the bullfrog, is considered an invasive species.
Oregon is a state located in the northwest part of the United States.
It is bounded on two sides by rivers and contains many forest resources.
Because frogs spend their larval stages in water and their adult lives on land, certain species can thrive in Oregon’s aquatic and terrestrial environments.
The adult forms of these creatures are the primary topic of this particular article.
Insects and other terrestrial arthropods make up the bulk of their food, although some will also consume frogs of a smaller size or the same species.
Snakes, birds, raccoons, small animals, and larger frogs are the most common predators that consume them.
Various types of frogs in Oregon make their homes in the areas surrounding swamps, ponds, lakes, and bogs. In addition, you can find them along the sides of streams and rivers.
They cannot survive in saltwater; thus, you will find them almost exclusively near either permanent or transitory sources of freshwater.
Frogs are often camouflaged with colors that are difficult to decipher to avoid being eaten by predators.
The color of their dorsal side matches the color of the ground or the surrounding flora, and some species can change their color to match the color of any surface they are on.
Because they want to escape falling prey to fish that live in the water, the underside of their bellies is white or another bright color.
Some species of frogs have foul tastes or make themselves less appealing to potential mates, but others are lethal.
An overview of the types of frogs in Oregon is contained in the following paragraphs.
You will learn their scientific names, as well as their sizes, lifespans, geographical ranges, preferred habitats, morphological descriptions, behaviors, male advertisement calls, and extra anti-predator strategies.
1. Northern Red-Legged Frog
- Scientific Name: Rana aurora
- Size: 5 to 13 cm (2 to 5.25 in)
- Average Lifespan: up to 15 years in captivity
Both Oregon and California are home to their respective populations of red-legged frogs. People can also find them in the province of British Columbia in Canada.
Northern red-legged frogs, also known as Rana aurora, and Rana aurora draytonii, are the two subspecies that fall under this species (California red-legged frog).
They stay around the edges of streams and ponds, either stagnant or moving very slowly. They should have vegetation so that the frogs have somewhere to hide from potential predators, the heat of the sun, and the cold of winter.
This species’ dorsal coloration is often a shade between reddish-brown and gray, and they have multiple indeterminate splotches on their backs that are a darker color.
In addition to folds on their back and sides, a thin stripe runs along the bottom of their jaw.
There are streaks of red on the ventral area of the lower abdomen and back limbs, and the ventral color overall is yellow.
They only have partial webs between their toes. There are certain distinguishing characteristics between the subspecies.
The northern subspecies do not have any vocal sacs, but the vocal sacs of the California species are paired. The skin of northern red-legged frogs is smooth, thin, and spotted-free.
On the other hand, California red-legged frogs are larger, have more scaly and bumpy skin, and have lighter spots in the middle.
There are observable differences between the sexes as well. A female’s average adult size is greater than a guy’s. Males are characterized by having thicker thumbs and broader forearms.
Like most other anurans, these types of frogs in Oregon prefer to spend solitary lives until the time comes to reproduce.
They are daytime-active frogs. As protection against predators, they dive headfirst into the water and swim as deep as possible. They do this in response to an attack by a predator.
2. Pacific Treefrog
- Scientific Name: Pseudacris regilla
- Size: 1.9 to 5 cm (0.75 to 2 in)
- Average Lifespan: 7 to 8 years
The Pacific tree frog is found in Mexico, Canada, and the United States. It is possible to find them in other states in the United States outside Oregon, including Alaska, Arizona, California, Nevada, Utah, and Washington.
You can also find them in the Pacific Northwest region of North America, where their name says they would be; however, contrary to what the name might suggest, they live on land.
They make their homes in areas with a high concentration of plant life, particularly near water bodies such as ponds, springs, swamps, streams, and other similar wet areas.
A characteristic mark in the shape of a Y is visible on the top of the skull of an individual of this species, located between the eyes.
It has several dark dots on its dorsal skin as well as on its legs. There are also some visible black lines running from the shoulders down through the eyes of the creature.
Although they spend most of their time on land, their bodies are physically suited for climbing. They have adhesive disks in the shape of circles on the tips of each of their toes. The female frogs are often larger than their male counterparts in the same species.
Each Pacific tree frog has a uniquely colored dorsal surface in comparison to other individuals of the species.
The coloration is generally a variety of shades ranging from lime green to brown. The level of humidity and temperature might cause a change in the color of their skin.
They are frogs that only come out at night. Their sound is similar to a fast “cree-creek” that is low and powerful.
They can change color, which aids in their ability to conceal themselves from potential threats. However, they cannot voluntarily alter the hue of their dorsal surface to better blend in with their environment.
3. Northern Leopard Frog
- Scientific Name: Lithobates pipiens
- Size: 5 to 11.5 cm (1.97 to 4.5 in)
- Average Lifespan: 9 years in the wild (only about 5% of the population)
They live in various environments, including woodlands, brushlands, and marshes. These frogs like to be near bodies of water that are either motionless or move very slowly and have plenty of vegetation and open space nearby.
They are of a size considered to be average. On their backs, they typically have a green or greenish-brown coloration.
Additional brown patches are organized in a circular pattern on their backs, sides, and legs.
A white fold down the middle of their backs is one characteristic that sets them apart. One can see the dorsolateral fold at the beginning of each eye.
The lips of northern leopard frogs have white lines that extend from their noses to each of their shoulders.
When viewed from below, the hue of their bellies is often white or greenish-white. Males are typically smaller than females, and in addition to paired vocal sacs, they have thickened thumb pads designed for mating.
These types of frogs in Oregon are nocturnal frogs, meaning that they are most active throughout the night. Their calls sound like a low, rumbling snore interspersed with occasional clicking and croaking sounds.
Northern leopard frogs will flee the area while squealing or screeching when they sense danger approaching.
They are also purposefully tinted in a manner that allows them to blend in with the natural colors of the surroundings in which they live. They are also capable of imitation.
Another species of frog, known as the pickerel frog, is similar in appearance to northern leopard frogs. They release dangerous poisons to their attackers and serve to dissuade them.
These northern leopard frogs coexist with pickerel frogs, imitating them and using the similarity to their advantage to escape being eaten by predators.
4. Oregon Spotted Frog
- Scientific Name: Rana pretiosa
- Size: 4.5 to 10 cm (1.8 to 3.94 in)
- Average Lifespan: usually over three years
This water frog species is indigenous to the Pacific Northwest and endemic to the Cascade Mountains. Both Canada and the United States of America are home to these frogs.
They have been classified as vulnerable since very few of them are left.
Oregon spotted frog is native to wetlands, where it breeds in shallow ponds with grasses and spends its winters hibernating in streams and springs.
You can find This frog species in three places in British Columbia, four in Washington, and around twenty-four in Oregon.
There is a good chance the dorsal will be brown, reddish-brown, or red. The frog’s dorsal skin on its back and sides is covered in tubercles and bumps.
Large black patches on the animal’s flanks, legs, and back can also be found.
The huge dots have an asymmetrical appearance, with hazy outlines and a lighter hue in their centers than at their peripheries where the edges meet.
The ventral coloring often consists of a reddish-orange or salmon tint and extends towards the groin and beneath the hindlegs.
The back legs of this particular kind of frog are not very long. Their rear feet have enormous webbed paws on all of their toes. There is a size difference between the sexes since females are significantly larger than males.
Oregon spotted frog is a nocturnal animal. Their vocalization is a five to fifty short sounds delivered in a tapping-like pattern.
Urbanization, the alteration and loss of habitat, predators, new competitors, and habitat drainage have contributed to their rarity and vulnerability as a species.
5. Rocky Mountain Tailed Frog
- Scientific Name: Ascaphus Montanus
- Size: 3.8 to 5.7 cm (1.5 to 2.24 in)
- Average Lifespan: 7 or 8 years to 15-20 years
The rocky mountain-tailed frog is a species that one can only find in the United States and Canada. Its natural habitats include the states of Oregon, Idaho, Montana, Washington, and British Columbia. You can find it in the Rocky and Columbia ranges.
These types of frogs in Oregon prefer to live in mountain streams with steep gradients and swift currents. It is most comfortable in permanently wooded streams with clean, frigid water, a substrate of boulders or cobble, and very little silt.
Their bodies may be brown, olive-gray, or reddish-brown, and they would have spots of yellow or gray. Their skin has a granular texture and a dark stripe runs across each eye. The hue of the ventral side of the body is cream, white, or pinkish pallor.
The Rocky Mountain-Tailed Frog is unique because it does not have tympana, which are external eardrums. The toes on the extremities of their hind legs are noticeably wider than the other toes.
“Tails” are pear-shaped organs that the males use for copulation and the internal fertilization of eggs. Internal fertilization is unique to this species of frog and the coastal-tailed frog.
These types of frogs in Oregon are most active at night and when the temperature is humid. Aside from that, they stay submerged and hide among the rocks and other debris.
These species use no mating calls because they do not have vocal sacs, and they do not make any sound.
6. American Bullfrog
- Scientific Name: Lithobates catesbeianus
- Size: 9 to 15.2 cm (3.5 to 6 in)
- Average Lifespan: 7 to 9 years in the wild, up to 16 years in captivity
The American bullfrog is not a natural species in Oregon; it is a non-native species that has become invasive in the state.
They are enormous, genuine frogs native to Canada and the United States, and you may find them in a wide range of habitats in both countries.
These frogs reside in a variety of environments, some of which are natural and some of which were created by humans.
They spend the majority of their lives in huge bodies of water that are always wet, such as lakes, swamps, ponds, marshes, canals, rivers, streams, and ditches.
Dorsally, bullfrogs might have a coloration that was either green or greenish-brown, and this color could be dark or bright.
The arms and legs are covered in black spots, while the backs and sides of the body might either be solid-colored or covered in dark dots.
These types of frogs in Oregon have lengthy legs, which are a beneficial adaptation for swimming and contribute to their powerful swimming.
Their toes are interconnected and quite huge. This species has a broad and flat head, and its eyes can either be yellow or have a golden-reddish bronze tint.
The size of the tympanum and the color of the neck change depending on gender. Males have necks that are golden in color and have tympana that are substantially larger than their eyes.
The tympana of females are either smaller than or the same size as the size of their eyes, and the color of their necks is either white or cream.
Because of their large size, bullfrogs can consume various creatures besides insects in their diet. They prey on types of frogs far smaller in size than they are.
Because of the introduction of bullfrogs in Oregon, several species of frogs have become threatened.
They are active both during the day and the night, although most of their activity occurs when the weather is humid and warm.
These types of frogs in Oregon become dormant throughout the colder months so they can enjoy the warm weather. Their call is like a rumbling “jug-o-rum” because of its deep and resonant quality.
7. Coastal Tailed Frog
- Scientific Name: Ascaphus truei
- Size: 2.2 to 5.1 cm (0.87 to 2.01 in)
- Average Lifespan: 2 to 9 years, up to 14 years
The coastal-tailed frog inhabits Canada and the United States, specifically in California, Washington, and Oregon, as well as in British Columbia.
This species thrives in diverse areas throughout the state of Idaho as well as the state of Montana. They prefer running water that is both chilly and swift.
As a consequence, they have developed several adaptations that are unusual among anurans. They need to be able to crawl among the rocks at the bottom of these streams, so their lungs are smaller, and the tips of their toes are tough.
They are relatively little frogs that get their dorsal coloring from the substrate. Their skin is typically rough and can have a variety of colors, including olive green, chocolate brown, or tan. Their toes have a faint webbed appearance, and the tips of their outer hind toes are round.
The head of a coastal-tailed frog is flattened and comparatively large. You can find a faint mark in the shape of a triangle in the space between its snout and its eyes.
Additionally, it has a dark stripe that runs from its snout to each of its shoulders.
Because they lack tympana, these types of frogs in Oregon are voiceless. They undergo internal fertilization, unlike the other types of anurans, which undergo external fertilization.
Their name comes from the fact that the organ they use for copulation is relatively short and resembles a tail.
We can summarize the size difference between males and females by noting that males are more diminutive than females.
During the breeding season, males acquire horny pads on their thighs that are black and are used to hold females. They are far more active throughout the night than during the day.
The Coastal-tailed Frog does not use calls to interact with its peers. They do not possess tongues, vocal sacs, ear bones, or tympana.
8. Columbia Spotted Frog
- Scientific Name: Rana luteiventris
- Size: 4.6 to 10 cm (1.81 to 3.94 in)
- Average Lifespan: 3 to 13 years in the wild
The Columbia spotted frog is a different species of frog found in Oregon. Alaska, the Yukon, British Columbia, Alberta, Montana, Wyoming, Idaho, and Nevada are some other states and territories in North America where you can find them.
These types of frogs in Oregon thrive best in freshwater bodies that are either completely still or move very slowly. Ponds, lakes, and streams with a slow current are common habitats for them.
The Columbia spotted frog is roughly the size of a human thumbnail. The back of it may be olive green, brown, or tan.
Its back, legs, and sides have numerous dark dots of varying sizes and shapes. The underside might be off-white, white, or yellow.
A line that is either yellowish or white is visible over its upper lip. It has a shorter snout, shorter legs, and webbed feet. It has folded skin in an irregular dorsal pattern all over its back.
These types of frogs in Oregon are most active during the day. It has a low-pitched call described as sounding like fast knocking or clucking. Their alarm sound is a screech that lasts for six seconds and can surprise their predators.
9. Foothill Yellow-Legged Frog
- Scientific Name: Rana boylii
- Size: 3.8 to 9 cm (1.5 to 3.54 in)
- Average Lifespan: 3 to 12 years in the wild
The United States of America and Mexico are home to this particular frog species. However, there has been a significant drop in the population in recent years in California.
Because of bullfrogs, the Foothill Yellow-Legged Frogs are on the verge of becoming endangered.
You can find these types of frogs in Oregon in wooded streams, rivers, and woods. They spend most of their time in or near water because they are primarily aquatic.
These frogs prefer locations that are rocky and have sunny banks.
They are not enormous or small; they are average size. The coloring on their backs could be uniform and solid or spotted with shades of a deeper color instead.
To blend in with their surroundings, the dorsal side of these types of frogs in Oregon may have a coloring that is gray, reddish, olive, or brown.
They may have a luminous spot on the upper lid of their eye. Their heads are broad and pointed, and the tympana on their ears is quite tiny. They have tubercles covering their dorsal skin, including the tympana.
Their ventral regions have a white, cream, or yellowish pallor. The groin and the hind legs carry a yellow hue.
Their forelimbs are significantly longer than their completely webbed hindlimbs, and their forelimbs are longer than their hindlimbs.
There is a significant size difference between the sexes, with females typically larger than males. During the mating season, males develop enlarged nuptial pads on their genitalia.
They also have a hard and swollen area underneath their first finger, whereas females lack the swelling but have a lengthier first finger.
Because they are a diurnal yet timid species, only a few are seen or spotted frequently. These frogs in Oregon will swim to the bottom of the pond or lake and hide among the rocks or vegetation there when they become scared.
10. Cascades Frog
- Scientific Name: Rana cascadae
- Size: 5 to 7.5 cm (1.97 to 2.95 in)
- Average Lifespan: up to 3 years in the wild
The Cascade Range is a mountain range in North America that runs through sections of British Columbia, Washington, Oregon, and California.
It is also home to the Cascades frog, which gets its name from this mountain range.
As a result of pollution and the decrease of the ozone layer, their populations are decreasing, making them a species on the verge of extinction.
They like to make their homes in ponds only a few feet deep, mountain meadows, woods, marshes, or small streams.
They are green frogs about the size of toads and have golden eyes and long legs. The dorsal side of their bodies is often brown, olive-brown, or olive. They have patches on their backs that are a darker pigment and are delineated.
The underside of the cascade frog is mottled around the groin and has a lighter coloration towards the groin and beneath the legs.
The underside also has a lighter coloration near the legs. This color might be yellow, yellow-orange, or tan with yellow undertones.
Additionally, there are black spots on the dorsal portion of their legs. This frog has a fold that runs along its back and is visible on both sides.
The webbing between its toes is incomplete, and the male has enlarged thumbs that are dark in color. The females are typically larger than their male counterparts.
Cascades Frogs are diurnal species, meaning they are more active during the day. Their courtship ritual consists of fast clucks or low-pitched laughing sounds, each lasting for half a second.
They travel slowly but attempt to swim more quickly when they feel danger.
