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Frogs & Toads of Montgomery County
Introduction to Frog and Toads
 Frogs and toads are amphibians of the order Anura. In Montgomery County we have identified ten species of frogs and two species of toads. However, worldwide there have been more than 3,700 species of the order Anura identified. The oldest frog fossil found dates back to the Jurassic Period (208 million -144 million years ago).
Frogs are tailless animals with moist smooth skin and webbed feet. Their long hind legs are adapted for jumping, and their bodies are squat. They spend part of the time in water and part on land, making them semi-aquatic. Frogs have teeth on the upper jaw, and live mainly on a diet of insects. When female frogs lay eggs, the eggs hatch and little aquatic larvae with gills are born, these are called tadpoles or pollywogs.
Toads have warty skin and slightly webbed toes. They have shorter hind legs and therefore cannot leap as far as frogs. Toads have no teeth, and the tongue is attached to the front of the mouth, so they have the ability to flick it out to capture prey. They have bright eyes and a horizontal pupil. They are hatched from eggs in the water into aquatic larvae with gills that are called tadpoles or pollywogs. Their diet consists primarily of insects, slugs, and other invertebrates.
Ecologists keep an eye on these amphibians because they are considered a good bioindicator for ecosystems. The health of the frog population is thought to correspond with the health of the ecosystem itself.
When you find an unhealthy frog, toad, or other amphibian, it is important to report it or them. Sometimes these creatures are found with malformations (irregularities), such as additional limbs, missing limbs, or malformed limbs.
| How to report amphibian malformations:
 The North American Reporting Center for Amphibian Malformations (NARCAM) Web site is now operated by the National Biological Information Infrastructure (NBII). Information previously found on the NARCAM Web site has been incorporated into NBII's FrogWeb: Amphibian Declines & Deformities website.
Other Contact Information:
FrogWeb
USGS Biological Informatics Office
302 National Center
Reston, Virginia 20192
703.648.6244 |
Frog Image Gallery
(Click on thumbnail image for larger version)
American Toad, Bufo americanus
 The American Toad is olive green to a reddish color, with warts on its back and on the hind legs. Its belly is speckled with dark markings. This toad grows up to the length of 9.0 cm. When reproduction occurs from the month of March to July, females lay a string of up to 6,000 eggs attached to vegetation in shallow pools. The American Toad is most active during the night and may be found in a variety of habitats including forests, farm lands, gardens and mowed lawns. They mostly eat crickets, moths, caterpillars, and millipedes. If you hear a “pleasant musical trill lasting up to 30 seconds” then you are listening to the call of the American toad.
Click here for a sample audio file.
Bullfrog, Rana catesbeiana
 The bullfrog is the largest frog in North America. It grows to 9-15 cm. in length. Its back is green to brown and its belly is an off white. The tympanic membrane (the membrane of the ear that vibrates sound) in males is larger than the eye, and in females it is the same size as the eye. They are nocturnal, although their call may be heard throughout the day. Between May and early fall females lay groups of about 12,000 eggs in a thin sheet covered by a film on the waters surface. The egg sheet is attached to submerged vegetation. The sheets of eggs have been noted to be up to five feet in width. The eggs hatch in about five days and the tadpoles are olive green and may grow up to seven centimeters before metamorphosis. Bullfrogs are found near large bodies of water, slow moving streams, and marshes. Bullfrogs require significant amounts of protective vegetative cover in their habitat. During winter, bullfrogs hibernate at the bottom of the water. Their diet consists of small mammals, snakes, frogs, insects, and crayfish.
Click here for a sample audio file.
Fowler’s Toad, Bufo fowleri
 The Fowler’s Toad grows to the length of 7.5 cm. They are a brownish green toad with a raised light colored stripe going down the middle of its back. On its back are dark splotches, each of these splotches contain at least three warts. The belly may have one dark splotch if any. From March to August females lay two strings of eggs in shallow pond water and stream edges. These toads are most active during the night and eat primarily insects. They are found in shallow water. Their call is described as a “Plaintive, descending, one to three second wraaaaah.”
Click here for a sample audio file.
Gray Treefrog, Hyla versicolor
 The Gray Treefrog is a small frog which only grows to 5.1 cm. The color of the frog depends on the frog's environment. It may range from gray to green to white to brown. It will always have a light rectangle shaped spot under the eye. Its back is covered with warts, and on its back legs the thigh area is a bright yellow with dark mottling. Between the months of August to April, females lay a clutch of up to 40 eggs on the water surface. Females lay many clutches per season. Within five days eggs tend to hatch. These frogs are most active during the night. They typically stay in trees or shrubs near the water. During mating season they spend more time on the ground then usual. The Gray Treefrog diet consists mainly of insects. Their call is describes as a “hearty, resonating trill, usually heard in spring and early summer.”
Click here for a sample audio file.
Green Frog, Rana clamitans
 The Green Frog grows to between 5.7 cm and 9.0 cm. Its back is a greenish brown with markings of the same color, and its belly is white. The frog has a dorsolateral fold (a raised stripe) starting from behind each eye that extends to the middle of its back
. Adult males and females may be told apart by looking for the yellow throat of the males. Another characteristic for telling the sexes apart is the size of the tympanic membrane (the membrane of the ear that vibrates sound). The male’s tympanic membrane is larger than the eye and the female's is smaller than the eye. When reproduction occurs the female attaches a small cluster of eggs to submerged vegetation in shallow bodies of freshwater. Tadpoles are green with black dots and some have yellow bellies. The green frog is generally found in areas that are close to shallow fresh water, such as streams, rivers, ponds, and lakes. Their diet consists mainly of worms, snails, centipedes, millipedes, spiders, ticks, mites, and insects.
Click here for a sample audio file.
Northern Cricket Frog, Acris crepitans
 The Northern Cricket Frog is a small frog that only grows to 3.8 cm. This frog may be bright green, yellow, dark brown, or any shade in between, with warty skin and a dark triangle between its eyes. From March to August, females lay small groups of eggs or single eggs in shallow water. The eggs may be scattered along the bottom with the rocks and sand, or attached to vegetation. When the eggs hatch, the tadpoles may be identified by the dark tip on their tail. This frog is more active during daylight, and is found in sunny areas near slow moving streams, wetlands, and ponds. They mainly eat centipedes, millipedes, spiders, mites, ticks, and insects. Listen for a shrill, measured clicking; this is the call of the Northern Cricket Frog.
Click here for a sample audio file.
Northern Leopard Frog, Rana pipiens
 The Northern Leopard Frog is considered an uncommon species in Montgomery County. This frog grows to the length of 9.0 cm. It has a dorsal coloration of brown to green with dark, circular spots outlined with a light margin. There is no light center in the tympanum, and on the upper jaw there is a light line present. There are two ridges on the back that extend from the snout to the groin. Mating occurs between March and April when females lay between 3-5000 eggs in a circular clump in ponds, attached to submerged vegetation. These frogs are found in all types of aquatic habitats including streams, wetlands, and ponds. The northern leopard frog mainly feeds on worms, insects, and other aquatic invertebrates.
Click here for a sample audio file.
Pickeral Frog, Rana palustris
 The Pickeral Frog grows to 4.5-9.0 cm in length. On its back are two parallel rows of dark squares or rectangles. The dorsolateral ridge (raised stripe) extends to the groin, and along the jaw there is a light colored stripe. The under side of the back legs are a bright yellow orange. Between March and May females lay about 2,500 eggs in clusters in pools and ponds. The Pickerel Frog is generally found meadow streams, bogs, and floodplains. They mostly eat spiders, centipedes, millipedes, insects, ticks, and mites.
Click here for a sample audio file.
Southern Leopard Frog, Rana sphenocephala
 The Southern Leopard Frog generally grows between 5-9 cm. Its dorsal coloration varies from a green to brown. There is a light marking on the tympanum and elongated dark spots. Mating occurs from winter thru spring, when females lay clusters of eggs in shallow water, attached to submerged vegetation. Usually many frogs lay their eggs in the same area. Within two weeks tadpoles hatch; within three months when they are about 7cm, metamorphosis occurs. The southern leopard frog is primarily nocturnal. It will occupy any freshwater habitat, and will wander away from water into protective vegetation. Their diet mainly consists of insects along with worms and arthropods.
Click here for a sample audio file.
Spring Peeper, Pseudacris crucifer
 The Spring Peeper is a very small gray to green colored frog that only grows to the length of 2.5 cm. A notable characteristic is the dark “X” on its back. It has large toe pads and dark markings between the eyes. During breeding season, which is March to April, the females lay about 900 eggs per clutch which are attached to floating vegetation. This frog is most active at night and may be found in wetlands, brushy environments, second growth stands, and under leafs. Their diet mainly consists of spiders, ticks, centipedes, mites, and insects.
Click here for a sample audio file.
Upland Chorus Frog, Pseudacris feriarum
 The Upland Chorus Frog grows to be about 2.0 -3.5 cm. Its’ back (or dorsal) is brown or gray with three lines running the length of the back. Across the upper lip is a white line; there is a black line that begins at the snout, goes through the eye and ends at the groin; and a black triangle is positioned between the eyes. The belly is light colored with dark splotches. Mating occurs between February and May. Females lay clumps of around 1000 eggs in shallow water attached to submerged vegetation. The upland chorus frog is generally found in wetlands, swamps, and grassy swales.
Click here for a sample audio file.
Wood Frog, Rana sylvatica
 The Wood Frog is a diurnal species which grows to about 3.5-7.0 cm in length. This frog has a black ‘mask” that extends from the snout thru its tympanum (ear drum). There is a light colored mid-dorsal stripe and the toes are not fully webbed. Dorsal coloration is generally brown, but may vary to a pinkish color or an olive green. Near the front two legs, on the white chest, there is a dark spot. The wood frog is considered an explosive breeder. They breed in small groups for just a few days in early spring. The females’ average clutch is about 1,700 eggs. They lay the eggs in shallow pools attached to submerged vegetation. Tadpoles are about 4.5cm in length and have a slightly patterned rounded tail fin. This species is mainly found in wetlands and will venture away from water when not breeding and hibernate in the forest debris. They generally eat all insects, mainly beetles and flies.
Click here for a sample audio file.
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