Are you curious about the common amphibians found in Oregon? Amphibians can be elusive and oftentimes hard to spot, but searching for them can be an enjoyable and rewarding experience. In this article, you’ll discover six of the most common and fascinating amphibians that call Oregon home. From the impressive American Bullfrog to the charming Pacific Treefrog, each species is accompanied by detailed pictures and range maps to aid in identification. So, if you’re eager to learn more about the diverse amphibian population in Oregon, keep reading!
6 COMMON Amphibians in Oregon (ID Guide)
Introduction
Are you interested in exploring the wonderful world of amphibians in Oregon? Well, you’re in for a treat! Oregon is home to a diverse range of amphibians, including frogs, toads, and salamanders. While these creatures can be elusive, the thrill of spotting them in their natural habitat is truly exhilarating. In this article, we will introduce you to six of the most common amphibians found in Oregon, providing you with identifying characteristics, habitat and range information, dietary preferences, and unique features of each species. So grab your field guide and get ready to embark on an exciting adventure into the fascinating world of amphibians in Oregon!
American Bullfrog (Lithobates catesbeianus)
Identifying Characteristics
The American Bullfrog is a striking amphibian with adult body lengths ranging from 3.6 to 6 inches. They are typically olive green in color, although some individuals may have gray or brown spots. One distinguishing feature of the bullfrog is its fully webbed back feet.
Habitat and Range
American Bullfrogs can be found in permanent bodies of water, such as swamps, ponds, and lakes. They are native to the green areas on the map, but have also been introduced to the red areas.
Diet
Bullfrogs are voracious eaters and have a diverse diet. They will consume almost anything they can fit into their mouths, including other frogs, fish, turtles, small birds, bats, rodents, insects, crustaceans, and worms. It’s not uncommon to see a bullfrog attempting to eat something as large as a baby duck!
Unique Features
One of the most distinctive features of the American Bullfrog is its deep call, which sounds like a bull bellowing. This call is used by males to attract females during the breeding season. Keep your ears open when you are near a body of water to listen for this unique sound.
Northern Leopard Frog (Lithobates pipiens)
Identifying Characteristics
The Northern Leopard Frog is a medium-sized amphibian, ranging from 2 to 4.5 inches in length. It has smooth green, brown, or yellow-green skin with large dark spots. Lighter-colored raised ridges can be seen extending down the length of its back.
Habitat and Range
These frogs can be found in eastern Oregon near slow-moving bodies of water that have plenty of vegetation. They are most commonly seen in or near ponds, lakes, streams, and marshes.
Diet
Northern Leopard Frogs feed on a variety of prey, including worms, crickets, flies, small frogs, snakes, and even birds. In fact, there have been reports of these frogs consuming bats!
Declining Populations
Unfortunately, Northern Leopard Frogs are experiencing declining populations in many areas. The exact cause of this decline is not fully understood but is believed to be a combination of habitat loss, drought, introduced fish, environmental contaminants, and disease. Efforts are being made to conserve and protect these beautiful frogs.
Pacific Treefrog (Pseudacris regilla)
Identifying Characteristics
The Pacific Treefrog is a small amphibian, typically reaching a length of 2 inches. The males are usually smaller than the females. Their coloration can vary, with most individuals being green or brown with pale white undersides. Some individuals may be reddish, gray, cream, or black. They have a dark mask across their eyes to the shoulders and uniformly bumpy skin.
Habitat and Range
These treefrogs have a wide range of elevations in Oregon, from sea level to 10,000 feet. They can be found in woodlands and meadows, although it’s interesting to note that despite being called a treefrog, they spend most of their time on the ground. They even seek shelter from predators in underground burrows.
Behavior
Pacific Treefrogs are known for their adaptability and resilience. They are able to tolerate a wide range of conditions, including both natural and human-altered environments. This adaptability has contributed to their abundance and widespread presence in Oregon.
Mating Call
During the spring breeding season, male Pacific Treefrogs emit a distinctive two-part call that sounds like “kreck-ek” or “rib-bit.” These calls can be quite loud, especially when multiple males are calling at the same time. If you happen to be near a breeding site, you’ll likely hear the chorus of Pacific Treefrogs serenading you with their enchanting melody.
Western Toad (Anaxyrus boreas)
Identifying Characteristics
The Western Toad is a medium-sized toad, with adult lengths ranging from 2 to 5 inches. They come in various colors, including yellowish, tan, gray, or green, with a pale stripe along their back. Dark blotches with rust-colored edges and warts adorn their bodies. Males have smoother, less blotchy skin compared to females.
Habitat and Range
As the name suggests, Western Toads can be found in the western part of the continent. They inhabit a wide range of habitats, including desert streams and springs, forests, lakes and rivers, and even backyard gardens with nearby pools.
Unique Movement
One interesting fact about Western Toads is that they don’t typically hop like most other toads. Instead, they have a unique walking style, picking up one or two legs at a time. This distinctive movement sets them apart and makes them easily recognizable when you encounter them in the wild.
Woodhouse’s Toad (Anaxyrus woodhousii)
Identifying Characteristics
Woodhouse’s Toads are small to medium-sized amphibians, with adult lengths ranging from 2.5 to 4 inches. They come in various colors, from gray to yellowish or olive green. Their bellies are light tan or buff, typically with very few dark spots on the chest.
Habitat and Range
These adaptable toads can be found in a variety of environments, including grasslands, deserts, floodplains, and developed areas. Interestingly, Woodhouse’s Toads that live in suburban areas have developed a unique feeding strategy. They wait under street lamps to catch and eat insects attracted to the light.
Unique Behavior
Woodhouse’s Toads have a distinctive round and stout shape, with short legs that may appear too small to support their bodies. This unique body shape sets them apart from other toad species and makes them easily distinguishable. Additionally, they have a short call that resembles a distressed sheep’s bleat.
Western Tiger Salamander (Ambystoma mavortium)
Identifying Characteristics
The Western Tiger Salamander is a medium-sized salamander, ranging from 3 to 6.5 inches in length. It has a greenish-yellow body with black markings, which can vary from large spots and stripes to small irregular shapes on the head, back, and tail. This species has a thick body and neck and a short snout.
Habitat and Range
Western Tiger Salamanders are secretive creatures that spend much of their time underground. They are commonly found in wet areas and are most likely to be seen moving and foraging on rainy nights. They seek shelter in burrows, which they either create themselves or borrow from other animals.
Underground Behavior
One interesting aspect of Western Tiger Salamanders is their underground behavior. They are not commonly seen on the surface and prefer the sheltered environment of their burrows. This behavior makes them a rare find for amphibian enthusiasts.
Different Morphs
Western Tiger Salamanders exhibit four distinct morphs as adults. These morphs are classified based on whether the salamander is aquatic or terrestrial and what it eats. For example, there are typical terrestrial individuals that eat insects and frogs, breathe above water, and spend more time on land. In contrast, there are aquatic morphs that have gills and breathe underwater. These individuals, known as paedomorphs, retain larval characteristics, including frilly, long gills.
Conclusion
Oregon is undoubtedly a treasure trove for amphibian enthusiasts. The six common amphibian species highlighted in this guide – the American Bullfrog, Northern Leopard Frog, Pacific Treefrog, Western Toad, Woodhouse’s Toad, and Western Tiger Salamander – represent the incredible biodiversity found in the state. Each species has its own unique characteristics, ranging from the American Bullfrog’s impressive size to the Western Tiger Salamander’s secretive underground lifestyle. By understanding and appreciating these incredible creatures, we can contribute to their conservation and ensure their continued presence in the beautiful landscape of Oregon.
References
- 6 COMMON Amphibians in Oregon (ID Guide). (n.d.). Retrieved from https://birdwatchinghq.com/6-common-amphibians-in-oregon-id-guide/