Rhode Island is a state in New England, a region in the northwestern part of the USA. It is known for its forested mountains, hayfields, and pastures. It is home to over 800 species of animals.
Out of this number, there are three (3) species of toads and seven (7) species of frogs in Rhode Island. This sums up to ten (10) anuran species in the state. This article provides some information that can be used to identify these species when they are seen or heard calling.
There are some general traits in frogs and toads. They are able to live both in water and on land, and they lack tails. Their eyes are widely spaced for clear vision across a wide range.
Their tongues are long and sticky for catching insects. They have external eardrums (tympana) and prominent parotid glands. In toads, these parotid glands and warts on their skin produce poisons to deter attackers.
As another antipredator mechanism, their dorsal skin is colored to match their surroundings. This helps them avoid the attention of most terrestrial predators.
Their ventral skin is usually white or some pale color in order to avoid the attention of aquatic predators. This is called cryptic adaptation to the environment, involving coloration. Some species can change their dorsal color too.
Frogs and toads have four webbed feet, with four digits on their forelegs and five on their hindlegs. Toads however have generally shorter legs than frogs, and they walk or crawl to move. Frogs have longer legs for hopping and jumping.
Also, toads have dry, rough, and warty skin with stockier bodies. The skin of frogs is usually moist and smooth, with their bodies more slender than the bodies of toads. Both animals are insectivores, although some larger species eat smaller frogs and conspecifics (others of the same species).
They are usually eaten by fish, larger amphibians, reptiles, birds, raccoons, river otters, and sometimes humans. To avoid or escape predators, most frogs rely on cryptic coloration and other techniques. Some are poisonous.
Information peculiar to each species that can be found in this article includes their geographic range, habitats, physical traits, behaviors, mating or advertisement calls, and additional anti-predator mechanisms.
Table of Contents
Species of Frogs in Rhode Island
1. American Bullfrog
- Family: Ranidae
- Scientific Name: Lithobates catesbeianus
- Other Names: Rana catesbeianus, American bullfrog, North American bullfrog
- Adult Size: 9 to 15.2 cm (3.5 to 6 in), record length 20.3 cm (8 in)
- Lifespan: 7 to 9 years in the wild, up to 16 years in captivity
The bullfrog is native to the Nearctic region, the subtropical, tropical, temperate and arctic region of North America spanning across parts of the USA, Canada, and Mexico. It has been introduced to Asia, Europe, and South America.
Frogs of this species are highly aquatic so they live around water bodies, preferring warm, still, and shallow water. They are usually found around bogs, lakes, rivers, or ponds.
Bullfrogs are the largest true (ranid) frogs in North America. Their backs could be colored in any shade of brown or green. They have spots of darker color on their backs and webbed hind limbs.
There is sexual dimorphism in this species. While males have yellow throats in the breeding season, females have white throats. The male’s tympana are much larger than its eye, but it is smaller than or the same size as the eye in the females.
Bullfrogs are both nocturnal and diurnal, but they show the most activity in warm and humid weather. Their low rumbling calls can be heard from far distances. The calls have been described as a “jug-o-rum”.
These frogs also eat snakes, salamanders, crustaceans, smaller frogs and other terrestrial vertebrates. They are eaten by humans as a source of frog legs but not by some animals, especially fish, because they are foul-tasting.
2. Gray Tree Frog
- Family: Hylidae
- Scientific Name: Hyla squirella
- Other Names: Rain frog, chameleon frog
- Adult Size: 2.2 to 4.1 cm (0.87 to 1.6 in)
- Lifespan: 8.5 years in captivity
Frogs of this species are endemic to the eastern part of the USA and southeastern region of Canada. They are commonly found in small areas full of trees, noticed living up to 20 meters above the ground.
Gray tree frogs usually have rough and warty skin, rougher than the average frog but smoother than the average toad. They have large, advanced, and adhesive toe pads adapted for climbing.
Their dorsal skin is usually gray in color, but there are frogs of this species in other colors like brown, green, and ivory. Black splotches can be noticed on their skin. Environmental factors like humidity and season may change this dorsal color.
Their ventral surface is usually white or some other whitish pigment. Black speckles can be found on this venter, around the groin area. Beneath each eye of a gray tree frog, there is usually a white mark.
Males and females show no sexual dimorphism. Physically, these frogs resemble Cope’s gray tree frogs, and their calls sound alike. The flute-like trill of a gray tree frog is however much shorter in duration.
Frogs of this species are nocturnal and crepuscular. To avoid predation, they live high in trees and change color to blend in with their surroundings. Their nocturnality and crepuscular activity also make them less noticed by potential attackers.
3. Green Frog
- Family: Ranidae
- Scientific Name: Lithobates clamitans
- Other Names: Rana clamitans, bronze frog, brown frog, cow frog
- Adult Size: 5.7 to 12.5 cm (2.3 to 4.92 in)
- Lifespan: up to 10 years in captivity
Green frogs are found in Rhode Island, Maine, Hawaii, Tennessee, Washington, Ohio, Kentucky, Mississippi and a lot of other US states. They usually live in or around ponds, lakes, and marshes of fresh water, and other slow-moving freshwater sources.
Females of this species are larger on average than males. They are found in various dorsal colors, including dark brown, brown, bronze, olive, green, and bluish. Individuals may come in two colors.
A green frog typically has two very pronounced ridges running down its back from each eye. It has very webbed feet. Its back has small spots of darker pigment scattered on it.
Its belly could be in different shades from white to yellow. Some sexual dimorphism may be seen in this species. Males have tympana much larger than their eyes while females’ tympana and eyes are fairly proportionate in size.
Green frogs are both diurnal and nocturnal. This means that they show activity both in the day and at night. The call of these frogs is a twang, resembling the sound a banjo string makes when plucked.
They are sometimes hunted by humans as a source of frog legs. They evade their predators by mimicry, taking advantage of the resemblance that they bear to bad-tasting mink frogs occurring around them.
4. Northern Leopard Frog
- Family: Ranidae
- Scientific Name: Lithobates pipiens
- Other Names: Rana pipiens, grass frog, meadow frog
- Adult Size: 5 to 11.5 cm (1.97 to 4.5 in)
- Lifespan: up to 9 years in the wild
This true frog species is native to parts of Canada and the United States.
It is the state amphibian of Minnesota and Vermont. It is also found in Rhode Island, Washington, Oregon, Utah, Arizona, New Mexico and Nevada.
Northern leopard frogs like to live around permanent bodies of slow-moving water with aquatic vegetation. They live in marshlands, brushlands, and forests, it prefer open spaces. They move far from the water when the breeding season is over.
Individuals are typically colored green, greenish-brown, or yellow-green dorsally. They have smooth skin covered in large oval spots, with each spot bordered by a halo of a lighter hue. This spotting resembles that on a leopard’s skin.
Underneath them, they are usually colored white or cream. There are two distinct ridges running along each side of the northern leopard frog’s back. Males are mostly smaller than females, with large thumb pads and dual vocal sacs.
They migrate to ponds during spring to breed and then leave for grasslands or meadows in the summer. They are more active in the night when breeding and more active during the day when foraging.
The call of a northern leopard frog is a short sound bearing similitude to snoring. This frog also eats smaller frogs. It escapes its predators by leaping away quickly and blending into the vegetative environment.
These frogs avoid their predators by taking advantage of their likeness to pickerel frogs, living around them to avoid being eaten. This is because although northern leopard frogs are not poisonous, pickerel frogs are.
5. Pickerel Frog
- Family: Ranidae
- Scientific Name: Lithobates palustris
- Other Names: Rana palustris
- Adult Size: 5.08 to 10.16 cm (2 to 4 in)
- Lifespan: N/A
The pickerel frog species is native to North America. It likes to live in cool streams with trees, swamps, springs, grassy fields, prairies, and weed-covered locations. It also prefers unpolluted water sources for breeding.
Individuals have two lines of dark chocolate colored spots on their backs, shaped like squares. These two lines are in between their two dorsolateral folds that extend to their groin area. They have a light line along their upper jaw.
The ventral coloration on pickerel frogs is usually white, bright yellow, or yellow-orange. Their bellies may have some mottling. The skin under their groins and hindlegs usually comes in any shade from bright yellow to orange pigment.
Males are typically smaller than females and these males have short forearms and swollen thumbs. The frogs are generally medium-sized so they are easily eaten by larger frogs.
Pickerel frogs are nocturnal. Their call is low and snore-like. To protect themselves from predators, they secrete toxic fluids that are poisonous enough to kill small mammals and cause irritation to humans.
6. Spring Peeper
- Family: Hylidae
- Scientific Name: Pseudacris crucifer
- Other Names: Peeper
- Adult Size: 1.9 to 3.5 cm (0.75 to 1.3 in)
- Lifespan: 0 to 3 years; up to 4 years in captivity
Frogs of this species can be found in places in North America like Rhode Island, Maine, Manitoba, Texas, Florida, and Cuba. They are adapted for climbing but they like living on the ground, in ponds, swamps, and pools.
Spring peepers are typically colored in various shades of brown, gray, or olive. Although more rarely, they can be found in reddish and yellow colors. These frogs are very small in size.
Ventrally, they are colored white or cream, with a dark cross on their backs and dark bands on their legs. Their feet are moderately webbed and they have large and adhesive pads on their fingers and toes, for climbing.
They are nocturnal. They hibernate during winter, and so much activity is not observed from them during this period. Their calls are chirp-like. These calls usually mark the beginning of spring, hence the name of the frog.
Diet is mainly small insects and arthropods. Predators of these frogs include salamanders, owls, birds, snakes, large spiders, and birds. Larger frogs may also eat the spring peeper because of its small size.
7. Wood Frog
- Family: Ranidae
- Scientific Name: Lithobates sylvaticus
- Other Names: Rana sylvatica, the frog with the robber’s mask
- Adult Size: 3.8 to 8.2 cm (1.5 to 3.25 in)
- Lifespan: 3 to 5 years in the wild
The wood frog is another species of frog in Rhode Island. Commonly distributed across North America, this species can be found in several locations within the United States and Canada.
This frog lives mostly on the ground or around trees, but it can also be found in marshes, swamps, meadows, and mixed forests. Woods frogs leave their primary habitats to breed in semi-permanent water bodies.
A wood frog has mask-like markings across its eyes, hence its other common name. These markings are black patches from each tympanum to the base of each of its forelegs. A white outline is present across its upper lip.
Frogs of this species come in diverse shades of gray, green, brown, tan, and rust. A mid-dorsal fold is seen running down their backs in a bright yellow-brown color. The ventrum is white in color.
There is sexual dimorphism in wood frogs. Males are smaller in size with the ventral part of their legs colorful. Females are larger, their white bellies fade to a yellow-orange pallor towards the legs, and they are more brightly colored dorsally.
Wood frogs are more diurnal, actively scrounging and feeding during the day. Their call sounds much like the clucking of a chicken. They employ their cryptic coloration and other measures to avoid and deter predators.
They produce poisons to irritate predators when captured or attacked. When captured, the wood frog lets out an alarm call, which is a piercing cry. This may startle or annoy the predator.
Species of Toads in Rhode Island
8. American Toad
- Family: Bufonidae
- Scientific Name: Anaxyrus americanus
- Other Names: Bufo americanus, hop toad
- Adult Size: 5 to 10 cm (1.97 to 4 in), record SVL of 11.1 cm (4.4 in)
- Lifespan: 1 to 10 years in the wild, up to 36 years in captivity
The American toad is found largely in parts of North America. It lives in Canada, Mexico, and the USA. Some locations include Chihuahua, James Bay, Quebec, California, Washington, Rhode Island, Oregon, and Mississippi.
There are three subspecies: the eastern American toad, the dwarf American toad, and the Hudson Bay toad. This species is very rampant because it comfortably lives in any habitat in which it can easily find semi-permanent water for breeding, dense vegetation for cover, and insects for food.
American toads have short legs, stout bodies, and thick, warty skin. Warts on the skin could be red or yellow, but the dorsal surface is usually colored brown, olive or gray. Skin color can change because of stress, temperature, or humidity.
The digits on this toad’s hindlegs are fully webbed. On the dorsum, there are several dark spots. Each spot has one or warts on it. Male and female American toads show sexual dimorphism.
Males have dark colored, usually black or brown in color. Females have white throats and lighter bodies. They are also bigger in size than the males.
The toad is nocturnal and is active when the weather is warm and humid. It may be found under rocks, stones, twigs, and other such things in the daytime. Its call is a long and high-pitched “bu-r-r-r-r-r”, usually 6-30 seconds long.
In case of attack or capture by a predator immune to their toxins, American toads blow up their skin with air to make them hard to swallow or urinate on themselves in order to be less appealing for their predators to eat.
9. Eastern Spadefoot
- Family: Scaphiopodidae
- Scientific Name: Scaphiopus holbrookii
- Other Names: Eastern spadefoot toad
- Adult Size: 4.5 to 7.8 cm (1.7 to 3.1 in)
- Lifespan: 5 to 9 years in the wild, 7 to 10 years in captivity
The eastern spadefoot is found in the southern part of the New England Region (where Rhode Island is), down to Florida along the Atlantic Coastal Plain, and past the Mississippi Valley and north into the state of Tennessee.
Individuals like sandy soil, moderate temperature, and rainy regions. They can be found in grasslands, ravines, pastures, farmlands, swamps and temporary pools. They like to burrow into the ground, covering themselves with leaves for protection and insulation.
Eastern spadefoots are dark in color, ranging from olive to black in shade. Ventrally, they may be gray, cream, yellowish white, or white. They have two conspicuous lines running along their backs that taper together at the posterior end.
The skin of this toad is warty and it has small parotid glands. Black spade-like protrusions are present on its hindlegs to aid burrowing. The color and shade of its skin are affected by environmental factors.
Eastern spadefoots are active both in the day and at night, but they are more diurnal. They are very active in humid weather. Their call is a low-pitched “waaaaa” repeated at short intervals.
To avoid predators, this toad quickly buries itself in the soil. Its skin is colored like the soil, an adaptation that helps the toad blend in with the soil. This in turn hides the toad from attackers.
10. Fowler’s Toad
- Family: Bufonidae
- Scientific Name: Anaxyrus fowleri
- Other Names: Bufo fowleri
- Adult Size: 5.1 to 9.5 cm (2 to 3.75 in)
- Lifespan: 5 years
Fowler’s toads are found in the eastern region of the United States, along the Atlantic coastal plain. They like to live in savannas with widely spaced trees and open canopy.
They can be found in grasslands that are conducive to the growth of grasses but not taller trees. They also like to live on beaches. Primarily, they prefer to live in open spaces.
They are medium-sized toads. Their backs are usually tan, gray, brown, or greenish-gray in color. They have dark or black spots on their backs, and each black spot could have three to six warts.
Fowler’s toads characteristically have a white or light mid-dorsal stripe. Their bellies are colored in a light shade and they possess a single gray spot. Typically, the male toads are darker in color and the females lighter.
They are primarily nocturnal but they are also active in the daytime. They however do not show activity in extreme heat or cold. Its call sounds like a baby crying or a sheep bleating, and it lasts for 2-5 seconds.
This species is considered to be at risk due to the activities of off-road vehicles, the use of chemicals in agriculture, and predation. They, like other toads, secrete poisons produced by their parotid glands from their skin.
Fowler’s toads employ other measures against predation. Because of their natural earth tones, they blend into their environments. If roughly handled by predators, they pretend to be dead by lying still.
What kind of frogs live in Rhode Island?
Seven (7) species or kinds of frogs live in Rhode Island. They are American bullfrogs, gray tree frogs, green frogs, northern leopard frogs, pickerel frogs, spring peepers, and wood frogs.
Where can I find frogs in Rhode Island?
In Rhode Island, frogs can be found living in swamps and moist forests, both coniferous and deciduous forests. In the breeding season, frogs can be found in wetlands without fish, like kettle ponds and vernal ponds.
There are three (3) species of toads and seven (7) species of frogs in Rhode Island. These anurans include abundant species like the American bullfrog and some facing the threat of extinction like Fowler’s toads.
Frogs and toads make natural landscapes more magical at night by the sound of their calls and voices. They are also important to the environment as they eat insects and serve as food to other bigger species of animals.
These anurans are heard calling mostly in the breeding season. Males and females meet at water bodies (called breeding pools) for reproduction. This season is usually from spring to fall although the timeline varies across species.
They are usually not heard or seen for some time in the hibernation period, usually during the winter. When in hibernation, frogs and toads stay in an inactive state to avoid expending energy while looking for food and warmth.
Hibernation helps them get through the winter, while aestivation helps them get through the summer. Some frogs and toads will bury themselves underground in extreme heat to avoid desiccation (drying up).
Frogs make good pets as long as they are not poisonous. They are small, affordable to purchase, and easy to take care of. Toads are poisonous and so they do not make great household pets.