Frogs and Toads in Your Pocket: A Guide to Amphibians of the Upper Midwest (Bur Oak Guide) [1 ed.] 1609380592, 9781609380595

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a bur oak guide

Frogs and Toads

in your pocket

A Guide to Amphibians of the Upper Midwest By Terry VanDeWalle Photographs by Suzanne L. Collins

Plains spadefoot Spea bombifrons

range: IA, KS, MO, NE, ND, SD

size: 1 1/2–2 inches description: Medium

▼ Eastern spadefoot

Scaphiopus holbrookii range: IL, IN, MO, OH size: 1 3/4– 2 1/4 inches description: Medium

brown or yellow toadlike amphibian with large, protruding eyes; vertically elliptical pupils; short legs; and large feet. Head, back, and legs mottled with dark brown. Two yellowish lines usually extend from eyes down back and come together to form an hourglass shape. No raised area or boss between eyes. Belly gray to white, unspotted. Skin with small warts that may be tipped in red. Parotoid glands small, round, not easily seen. 1 long, sickle-shaped digging spur or spade on heel of each hind foot. habitat: Open fields and wooded areas with loose, sandy soils; breeds in temporary pools and flooded fields voice: Series of explosive groans, “errrrrrah,” similar to young crows natural history: These amphibians spend most of their time underground in burrows they dig using the spades on their hind feet. They become active on warm, rainy nights when they come out of their burrows to breed. Feed on a variety of insects. Breed April to September. Adapted to temporary waters, eggs hatch in a few days and tadpoles transform in 2 to 3 weeks. similar species: Plains spadefoot has raised area or boss between eyes and short, wedgeshaped spade on heel of each hind foot. American, Fowler’s, Woodhouse’s, and Great Plains toads have well-developed warts, cranial ridges, and parotoid glands; 2 large spades on heels of hind feet; and pupils that are horizontally oval.

gray, tan, or brown toadlike amphibian with large, protruding eyes; vertically elliptical pupils; short legs; and large feet. Head, back, and legs mottled with irregular dark marks. May have 2 to 4 faint light lines on back. Raised area or boss between eyes. Belly gray to white, unspotted. Skin with small warts that may be reddish. Parotoid glands small, round, not easily seen. 1 short, wedge-shaped digging spur or spade on heel of each hind foot. habitat: Prairies and open floodplains with loose, sandy soils; breeds in temporary pools and flooded fields voice: Snorelike growl repeated every 1 to 2 seconds natural history: This amphibian may spend all but 2 weeks of the year underground in burrows it digs using the spades on its hind feet. Like the eastern spadefoot, it becomes active on warm, rainy nights when it comes out of its burrow to breed. Feeds on a variety of insects, including beetles, grasshoppers, and caterpillars. Breeds April to September. Adapted to temporary waters, eggs hatch in a few days and tadpoles transform in 2 to 3 weeks. similar species: Eastern spadefoot lacks raised area or boss between eyes and has long, sickle-shaped spade on heel of each hind foot. American, Fowler’s, Woodhouse’s, and Great Plains toads have well-developed warts, cranial ridges, and parotoid glands; 2 large spades on heels of hind feet; and pupils that are horizontally oval.

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American toad

Great Plains toad

range: IL, IN, IA, KS, MI, MN, MO, NE, ND, OH, SD, WI size: 2–4 1/4 inches description: Large gray,

range: IA, KS, MN, MO, NE, ND, SD size: 2–3 1/2 inches description:

Anaxyrus americanus

brown, or reddish brown toad with warty skin; many dark spots on back; and heavily mottled chest and belly. Usually 1 or 2 warts on each of largest dark spots on back, 1 large and 1 small digging spur or spade on heels of hind feet. Enlarged warts on lower part of leg. May have narrow light stripe down middle of back. Large, kidney-shaped parotoid glands behind eyes may be separated from or connected by a spur to distinct cranial ridges between eyes. habitat: Prairies, forests, marshes, farmland, urban areas; breeds in rivers, ponds, roadside ditches voice: High-pitched musical trill lasting up to 30 seconds natural history: When attacked, this common and widespread toad produces a substance from the large warts on its back that can be poisonous to small animals. It may also inflate itself with air, making it difficult to swallow, and it often releases urine when frightened. Feeds on insects and earthworms. Breeds April to early May. Tadpoles transform in 1 to 2 months. similar species: Fowler’s toad has 3 or more warts on each of largest spots on back, unspotted chest and belly, warts on upper and lower legs nearly equal in size, parotoid glands touch cranial ridges. Woodhouse’s toad has unspotted chest and belly, parotoid glands touch cranial ridges. Great Plains toad has cranial ridges between eyes that come together and meet at snout to form raised knob.

Anaxyrus cognatus

Medium gray, brown, or greenish toad with warty skin; distinctive large dark spots outlined in white or cream; and unspotted belly. Each dark spot contains numerous warts, 1 large and 1 small digging spur or spade on heels of hind feet. May have light line down middle of back. Hind legs are banded, front legs banded or spotted. Parotoid glands behind eyes touch cranial ridges. Cranial ridges between eyes come together and meet at snout to form raised knob. habitat: Prairies and nonnative grasslands; breeds in rivers, ponds, roadside ditches voice: Loud, continuous, pulsating trill with mechanical quality lasting 20 to 50 seconds natural history: This prairie toad is active at night and is a skilled burrower, spending its days underground. Feeds on insects such as beetles and ants. Breeds April to late June. Each female may lay up to 20,000 eggs. Tadpoles transform in 1 to 2 months. similar species: American, Fowler’s, and Woodhouse’s toads have cranial ridges between eyes that do not come together and meet at snout to form raised knob.

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tadpoles American toad: Up to 1 inch long, black or dark brown with metallic spots, tail fin clear with rounded tip. Blanchard’s cricket frog: Up to 1 1/2 inches long, appears flattened, tail fin faintly mottled, tip of tail black. Boreal, midland, or upland chorus frog: Up to 1 3/16 inches long, upper tail fin higher than lower tail fin, tail fin clear or with light flecks. Bronze or green frog: Up to 4 inches long, few black spots on body, tail and tail fin heavily spotted. Bullfrog: Up to 4 1/2 inches long, black spots on upper side of body and tail. Eastern narrowmouth toad: Up to 13/16 inch long, mostly black, never gray or brassy, belly dark with pale blotches and mottling, tail stripe bright and distinct. Eastern or Cope’s gray treefrog: Up to 1 1/8 inches long, tail fin medium in height, clear band next to tail muscle. Eastern spadefoot: Up to 2 inches long, dark brown to bronze, clear tail fin, no marks on tail muscle. Fowler’s toad: Up to 1 inch long, black or dark brown with metallic spots, tail fin clear with rounded tip. Great Plains narrowmouth toad: Up to 15/16 inch long, grayish olive, flat, wide, tip of tail black. Great Plains toad: Up to 1 inch long, black or dark brown with metallic spots, tail fin clear with rounded tip. Mink frog: Up to 1 3/8 inches long, bright green to yellow-green with dark spots, reddish tail fin. Northern crawfish frog: Up to 2 1/2 inches long, series of pits along sides of body. Northern leopard frog: Up to 2 1/2 inches long, dark back, cream belly, tail lighter than belly. Northern spring peeper: Up to 1 1/8 inches long, tail fin medium in height, clear band next to tail muscle. Pickerel frog: Up to 2 1/8 inches long, few scattered marks on body, tail heavily marked with dark mottling. Plains leopard frog: Up to 2 1/2 inches long, upper side light brown or gray, spots on back. Plains spadefoot: Up to 1 7/8 inches long, tan or brown, clear tail fin, tail muscle outlined with dark pigment. Southern leopard frog: Up to 2 1/4 inches long, few faint markings on body and tail. Wood frog: Up to 1 7/8 inches long, brown with greenish sheen, tail fin clear ending in sharp point. Woodhouse’s toad: Up to 1 inch long, black or dark brown with metallic spots, tail fin clear with rounded tip. tail fin

tadpole

tail muscle

developing legs

this key to adult frogs and toads is organized into a series of num-

bered paired choices. Beginning with number 1, for each pair, choose the description that best fits the animal you wish to identify. Move to the next numbered pair indicated at the end of the description. Continue until you reach a description that ends in the name of the animal.

▼ Eastern narrowmouth toad Gastrophryne carolinensis

range: IL, KS, MO size: 7/8–1 1/4 inches description: Small, plump olive, brown, reddish brown, or nearly black amphibian with spotted or mottled belly. May have narrow stripe down back. Skin moist, smooth with no warts or ridges. Head small compared to rest of body, very pointed snout. Fold of skin across back of head behind eyes. Legs short, toes lack webbing and toe pads. No external tympanum. habitat: Open, moist areas with abundant cover; breeds in ponds, lakes, marshes, roadside ditches voice: Buzzy, nasal “waaaaaa” similar to cry of a lamb. May sound like Fowler’s toad but shorter and more buzzy. natural history: Although called a toad, this is actually a frog. When not breeding, this little frog is found in loose soil beneath rocks, rotting logs, bark, or other objects. One of the few amphibians to feed regularly on ants, it uses the fold of skin on the back of its head to keep them away from its eyes. Breeds May to June. Tadpoles transform in 1 to 2 months. similar species: Great Plains narrowmouth toad has lighter overall coloration, unspotted belly, and lacks prominent marks on back.

Great Plains narrowmouth toad

Gastrophryne olivacea range: KS, MO, NE size: 7/8–1 1/2 inches description: Small, plump gray, tan, or olive-tan amphibian with white unspotted belly; no prominent marks on back. Small black spots may be scattered over back and legs. Skin moist, smooth with no warts or ridges. Head small compared to rest of body, very pointed snout. Fold of skin across back of head behind eyes. Legs short, toes lack webbing and toe pads. No external tympanum. habitat: Grasslands, rocky and wooded hills, edges of marshes; breeds in roadside ditches, temporary ponds, flooded fields voice: High-pitched short peep followed by nasal buzz lasting 1 to 4 seconds, “peep-waaaaaa,” similar to the buzz of an angry bee natural history: Although called a toad, this is actually a frog. When not breeding, this little frog is found in loose soil beneath rocks or in the burrow of other animals, including tarantulas. One of the few amphibians to feed primarily on ants, it uses the fold of skin on the back of its head to keep ants away from its eyes, and its skin produces a toxic substance that protects it from ant bites. Breeds May to early July. Tadpoles transform in 1 to 2 months. similar species: Eastern narrowmouth toad has darker overall coloration, spotted or mottled belly, and prominent markings on back.

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Woodhouse’s toad Anaxyrus woodhousii woodhousii

range: IA, KS, MO, NE, ND, SD size: 2 1/2–4 inches description: Medium

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Fowler’s toad

Anaxyrus fowleri range: IL, IN, IA, KS, MI, MO, OH size: 2–3 inches description:

Medium gray, brown, or tan toad with warty skin; large dark spots on back arranged in pairs on either side of light stripe down middle of back; and virtually unspotted chest and belly; spots if present are limited to small one on chest. Usually 3 or more warts on each dark spot on back, 2 large digging spurs or spades on heels of hind feet. Warts on upper and lower legs nearly equal in size. Parotoid glands behind eyes touch cranial ridges between eyes. habitat: Open woodlands, fields, areas next to marshes with sandy soils; breeds in rivers, ponds, roadside ditches voice: Buzzy, nasal trill lasting 1 to 5 seconds, similar to a crying baby. Very similar to Woodhouse’s toad but higher in pitch. natural history: Formerly considered a subspecies of Woodhouse’s toad, adult Fowler’s toads are active day and night. During dry periods and winter, they burrow underground. Feed on insects, spiders, and earthworms. Breed April to late June. Tadpoles transform in 1 to 2 months. similar species: American toad has 1 or 2 warts on each of largest spots on back, heavily spotted chest and belly, warts on upper legs smaller than warts on lower legs, parotoid glands separated from cranial ridges or connected by spur. Woodhouse’s toad is very similar in appearance but has smaller, irregular dark spots on back that contain 1 to several warts, slightly less well developed cranial ridges. Great Plains toad has cranial ridges between eyes that come together and meet at snout to form raised knob.

gray, brown, or tan toad with warty skin; light stripe down middle of back; irregular dark spots on back; and virtually unspotted chest and belly; spots if present are limited to small one on chest. Usually 1 to several warts on each dark spot on back, 2 large digging spurs or spades on heels of hind feet. Warts on upper and lower legs nearly equal in size. Parotoid glands behind eyes touch cranial ridges between eyes. habitat: Grasslands, marshes, swales, river bottoms with sandy soils; breeds in rivers, ponds, roadside ditches voice: Short, nasal trill lasting 1 to 3 seconds, similar to a crying baby. Very similar to Fowler’s toad but lower in pitch. natural history: Active day and night, this toad may eat as much as 67% of its weight in a single day. During dry periods and winter, it burrows underground. Feeds on spiders and a variety of insects. Breeds April to late June. Tadpoles transform in 1 to 2 months. similar species: American toad has 1 or 2 warts on each of largest spots on back, heavily spotted chest and belly, warts on upper legs smaller than warts on lower legs, parotoid glands separated from cranial ridges or connected by spur. Fowler’s toad is very similar in appearance but has larger dark spots on back arranged in pairs on either side of light stripe down middle of back, 3 or more warts on each dark spot on back. Great Plains toad has cranial ridges between eyes that come together and meet at snout to form raised knob.

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Upland chorus frog

Pseudacris maculata

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Pseudacris triseriata

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Midland chorus frog

Boreal chorus frog

range: Boreal: IA, MN, NE, ND, SD,

WI; midland: IL, IN, IA, MI, MN, MO, NE, OH, SD, WI; upland: IL, IN, MO, OH size: 3/4–1 1/2 inches description: Small tan, brown, or gray nonclimbing frog with 3 dark brown or gray stripes down smooth back. Middle stripe may break up into rows of spots. White stripe on upper jaw, dark stripe running from snout through eye. Belly whitish with scattered dark flecks. Toe pads small, no webbing between toes. Boreal chorus frog has short legs, particularly segment below knee; stripes on back are visible or nearly absent; central stripe may be broken; stripes on sides run from snout through eye and end along side of body. Midland chorus frog has longer legs, lower segment longer in relation to rest of leg compared to boreal chorus frog; stripes on back are visible or nearly absent; central stripe is most often solid; stripes on sides run from snout through eye and end before groin. Upland chorus frog may have 3 stripes on back; if present, stripes most often break up into spots; stripes on sides run from snout through eye and into groin.

Pseudacris feriarum

habitat: Marshes, ponds, lakes, streams, roadside ditches voice:

Series of rapid “creaking” clicks that sound like a thumb rubbing along the stiff teeth of a small comb. Calls both day and night. Males call from edge of water or floating on water, sometimes in large choruses. natural history: Often the first frogs to be heard calling in spring, sometimes as early as mid March. Males may be seen calling from top of ice or snow. Feed on small insects, spiders, and other invertebrates. Breed March to May. Tadpoles transform in approximately 2 months. similar species: These three species look and sound nearly identical, but ranges of boreal and upland chorus frogs do not overlap. Boreal chorus frog has shorter legs than midland chorus frog and a central stripe on back that may be broken. Upland chorus frog has stripes on back that most often break up into spots, whereas midland chorus frog has a solid central stripe. Northern spring peeper has X-shaped mark on back. Wood frog is larger and has dorsolateral fold.

Eastern gray treefrog Hyla versicolor

Cope’s gray treefrog Hyla chrysoscelis

range: Eastern: IL, IN, IA, KS, MI,

MN, MO, NE, OH, SD, WI; Cope’s: IN, IA, KS, MI, MN, MO, NE, OH, SD, WI size: 1  1/4–2 1/2 inches description: Medium gray, green, or brown treefrog usually with few irregularly shaped dark blotches on back; white spot under eye; and dark bars on front and hind legs. Color changes from dark gray to light green depending on temperature and background color. Belly white, inside of hind legs yellow. Large, easily seen toe pads on front and hind feet. Eastern gray treefrog is slightly larger with warty skin, blotches on back bordered by black. Cope’s gray treefrog is smaller with smoother skin, blotches on back not bordered by black. habitat: Woodlands and urban areas; breeds in woodland pools, roadside ditches, marshes, bogs

voice: Short melodic trill lasting approximately half a second is repeated every few seconds. Call of Cope’s is faster and harsher. Call rate of both species is slower when colder and faster when warmer. natural history: Hibernates on land in woodlands under leaf litter, rotting logs, or other debris and produces a natural body antifreeze. Feeds primarily on terrestrial insects and spiders. Breeds late April to August. Tadpoles transform in approximately 2 months. similar species: These two species of treefrogs look nearly identical; there is no reliable way to tell them apart based on appearance or call. The only positive way is by chromosome number: Cope’s has 24, eastern has 48. Northern spring peeper is not warty, has X-shaped mark on back.

▼ Northern leopard frog

Plains leopard frog

range: IL, IA, IN, MI, MN, MO, NE, ND, OH, SD, WI size: 2–3 1/2 inches description: Medium brown or green

range: IL, IN, IA, KS, MO, NE, SD size: 2–3 3/4 inches description:

Lithobates pipiens

nonclimbing frog with rounded dark spots on back and sides that are usually outlined in lighter color and mostly larger than eye. Dark crossbars on tops of legs. White line along upper jaw. Distinct dorsolateral fold extends to groin. Belly white or cream, sometimes with faint yellow tint on undersides of legs. Most individuals have dark spot on snout and unspotted tympanum. habitat: Wet meadows, marshes, roadside ditches, and grassy edges of lakes, ponds, and streams voice: Long, rattling snore lasting 3 seconds or longer, similar to running a finger along the surface of an inflated balloon. Often mixed with grunts and squeaks. natural history: This familiar frog of biology classrooms may be seen far from water during summer months. Winters are spent lying on the bottom of small streams and marshes. Feeds on a variety of adult and larval insects. Breeds April to May. Tadpoles transform in 1 to 2 months. similar species: Plains leopard frog lacks light rings around spots on back, dorsolateral fold is broken near groin and offset toward middle of back. Southern leopard frog lacks light rings around spots on back and dark spot on snout, has pointed snout and distinct white spot on tympanum. Pickerel frog has paired squarish spots on back and bright yellow or orange on groin and underside of thighs. Northern crawfish frog has mottled jaws, spots on back are crowded together, no white line along upper jaw.

Lithobates blairi

Medium gray or brown nonclimbing frog with rounded dark spots on back and sides that are not outlined in lighter color. Dark crossbars on tops of legs. White line along upper jaw. Dorsolateral fold broken near groin and offset toward middle of back. Belly white with faint yellow tint on undersides of legs. Most individuals have dark spot on snout and single white spot on tympanum. habitat: Prairies, marshes, old fields, roadside ditches near streams or ponds voice: Series of 2 to 4 chucking notes, “chuck-chuckchuck,” repeated several times natural history: The plains leopard frog occurs together with the southern leopard frog in some places; the two species may breed with each other. Feeds on a variety of insects and spiders. Breeds March to April. Tadpoles transform in midsummer. similar species: Northern leopard frog has light rings around spots on back, dorsolateral fold is complete and extends to groin. Southern leopard frog has complete dorsolateral fold that extends to groin, lacks dark spot on snout. Pickerel frog has paired squarish spots on back and bright yellow or orange on groin and underside of thighs. Northern crawfish frog has mottled jaws, spots on back are crowded together, no white line along upper jaw.

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Northern crawfish frog

Wood frog

range: IL, IN, KS, MO size: 2 1/2– 4 1/4 inches description: Large tan to light gray nonclimbing frog with many dark spots on back crowded together and outlined in lighter color. Large head with mottled jaws, no white line along upper jaw, distinct humped back when sitting, distinct dorsolateral fold extending from eye to groin. Belly white, unspotted. habitat: Low, wet prairies; woodlands; floodplains; brushy fields voice: Low, rumbling snore lasting less than a second, “wwahhhhh.” Chorus of males may sound like pigs at feeding time. natural history: This secretive frog is seldom seen; it spends much of the year underground in mammal or crawfish burrows and sometimes storm sewers. Feeds on insects, crawfish, and other amphibians. Breeds March to April. Tadpoles transform by midsummer. similar species: Northern, plains, and southern leopard frogs and pickerel frog have white line along upper jaw. Plains leopard frog has dorsolateral fold broken near groin and offset toward middle of back. Pickerel frog has paired squarish spots on back and bright yellow or orange on groin and underside of thighs.

range: IL, IN, MI, MN, MO, ND, OH, SD, WI size: 2 1/2–4 1/4 inches description: Small to medium tan

Lithobates areolatus circulosus

Lithobates sylvaticus

to reddish brown nonclimbing frog with distinctive dark mask on sides of face covering lower part of eye. White line along upper jaw, distinct dorsolateral folds extending from eye to groin. Dorsolateral folds may have dark lines or spots. Back may have scattered black dots or white vertebral stripe, legs may have dark crossbars. Belly white, unspotted. habitat: Moist forests and bottomland forests, breeds in woodland pools and ponds voice: Ducklike quacking or cackling consisting of several notes in rapid succession natural history: This northern frog is one of the earliest breeders, moving to its breeding ponds with the first spring rains, sometimes with snow still on the ground. Feeds on insects, spiders, and other invertebrates. Breeds mid February to mid March in the south, mid March to April in the north. Tadpoles transform by May or June. similar species: Chorus frogs are much smaller, have 3 stripes on back, lack dorsolateral folds. Young bronze and green frogs may be similarly colored but lack dark mask on sides of face.

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Blanchard’s cricket frog

Northern spring peeper

range: IL, IN, IA, KS, MI, MN, MO, NE, OH, SD, WI size: 3/4–1 1/2 inches description: Small olive-brown

range: IL, IN, IA, KS, MI, MN, MO, OH, WI size: 3/4–1 3/8 inches description: Small tan, brown, or

Acris blanchardi

nonclimbing frog with warty skin; green, red, or brown stripe on back; dark triangle between eyes. Hind legs long with dark stripe on inner thigh. Belly white, males with dark throat. Tiny toe pads on front and hind feet, hind feet with extensive webbing. habitat: Muddy banks along edges of ponds, lakes, rivers, streams voice: Series of metallic notes that sound like glass or steel marbles tapping together, “gick, gick.” Starts out slow and speeds up. Calls both day and night. Males call while floating on water or on mats of vegetation. natural history: When frightened, this little frog jumps into water to escape but immediately swims back to shore. Feeds on terrestrial insects and spiders. Breeds late April to August. Tadpoles transform by mid September. similar species: Chorus frogs have white stripe on upper jaw and 3 dark stripes on back. Northern spring peeper is not warty, has Xshaped mark on back.

Pseudacris crucifer crucifer

gray treefrog with smooth skin and dark, X-shaped mark on back; dark spot or narrow line between eyes; dark crossbands on tops of legs. Colder frogs darker, warmer frogs lighter. Belly white, sometimes with dark flecks; males with folded skin under throat. Upper jaw extends beyond lower jaw. Small toe pads, hind feet webbed. habitat: Woodlands; breeds in marshy areas, roadside ditches, ponds voice: Series of high-pitched, birdlike “peeps” repeated about once per second or faster. Calls both day and night. Males may call in loud choruses of many individuals. natural history: One of the first frogs to call in spring. Hibernates in woodlands under leaf litter, rotting logs, or other debris and is one of the frogs that can withstand partial freezing. Hunts in low vegetation and feeds primarily on terrestrial insects and spiders. Breeds late February to May. Tadpoles transform in approximately 2 months. similar species: Chorus ▼ frogs have white stripe on upper jaw and 3 dark stripes on back. Blanchard’s cricket frog has warty skin; green, red, or brown stripe on back; and dark triangle between eyes. Gray treefrogs are warty, lack distinct X-shaped mark on back.

▼ Bullfrog

Bronze frog

range: IL, IN, IA, KS, MI, MN, MO, NE, OH, SD, WI size: 3 1/2–8 inches description: Large green, olive, or

range: Bronze frog (L. c. clamitans):

Lithobates catesbeianus

brown nonclimbing frog sometimes with brown or black spots or blotches on back, especially young frogs. Tops of legs may have dark bars. Lacks dorsolateral fold, ridges border tympanum. Belly white to yellow, sometimes with spots. Male tympanum distinctly larger than eye, yellow throat. Female tympanum approximately same size as eye, white throat. Webbing on hind foot nearly complete. habitat: Permanent lakes, ponds, marshes, rivers, streams voice: Loud series of bass notes sounding like “jug-o’-rum” and resembling the bellowing of a bull. When frightened, often gives a single “yelp” as it jumps into water. natural history: This large frog has been introduced by humans into many areas where it has resulted in the loss of smaller native frogs. It is an aggressive predator that will eat anything it can catch, including insects, other frogs, snakes, small turtles, mice, and birds. Breeds late April to August. Tadpoles overwinter and transform the following summer. similar species: Bronze and green frogs have dorsolateral folds along both sides of back.

Lithobates clamitans IL, MO; green frog (L. c. melanotus): IL, IN, IA, KS, MI, MN, MO, OH, WI size: 2 1/4–4 1/4 inches description: Medium green, olive, or brown nonclimbing frog with dark spots on back and sides and dark crossbars on tops of legs. Occasionally, some individuals lack yellow pigment in skin, resulting in partially or completely blue back. Upper jaw mottled. Dorsolateral fold ends at midback. Belly white, sometimes with light mottling. Male tympanum distinctly larger than eye, bright yellow throat. Female tympanum approximately same size as eye, white or pale yellow throat. Webbing on hind foot approximately halfway to tip of 2d toe. habitat: Shallow, weedy areas around lakes, ponds, rivers, creeks, swamps, marshes, roadside ditches voice: Single explosive “plunk,” sounding like a plucked banjo string. Calls may be repeated in series. When frightened, often gives a single “eek” as it jumps into water. natural history: Feeds primarily on insects and other invertebrates, but adults may eat other frogs. Breeds May to mid September. Tadpoles overwinter and transform the following summer. similar species: Bullfrog lacks dorsolateral fold. Mink ▼ frog has spots or lengthwise stripes on legs, not bars; webbing on hind foot extends to tip of 5th toe; musky, rotten onion, or minklike smell when handled; plain green upper jaw.

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Southern leopard frog

Pickerel frog

range: IL, IN, IA, KS, MO, OH size: 2–3 1/2 inches description:

range: IL, IN, IA, KS, MI, MN, MO, OH, WI size: 1 3/4–3 1/4 inches description: Small to medium gray

Lithobates sphenocephalus utricularius Medium tan, brown, green, or mixed brown and green nonclimbing frog with rounded dark spots on back and sides that are not outlined in lighter color and mostly smaller than eye. Broken bars or spots on tops of legs. White line along upper jaw. Head long and pointed. Distinct dorsolateral fold extends to groin. Belly white. Most individuals lack dark spot on pointed snout and have single white spot on tympanum. habitat: Creeks, rivers, sloughs, marshes, ponds, lakes voice: Series of 5 or more chucking notes delivered as a stutter too fast to count, “chu-huhu-hu-huck.” Males call while floating in water. May sound like plains leopard frog when cold. natural history: May be seen far from water during summer months. Feed on a variety of insects. Breed February to mid April, autumn in the south. Females lay up to 5,000 eggs. Tadpoles transform by late spring or summer. similar species: Plains leopard frog has dorsolateral fold broken near groin and offset toward middle of back. Northern leopard frog has light rings around spots on back and dark spot on snout, lacks distinct white spot on tympanum. Pickerel frog has paired squarish spots on back and bright yellow or orange on groin and underside of thighs. Northern crawfish frog has mottled jaws, spots on back are crowded together, no white line along upper jaw.

Lithobates palustris

or tan nonclimbing frog with 2 parallel rows of dark brown squarish spots on back between wide dorsolateral folds that extend to groin. Spots may fuse to form rectangles. Belly white, groin and underside of thighs bright yellow or orange. White line along upper jaw. habitat: Grassy edges of ponds, rivers, and spring-fed streams; prefers cool water voice: Harsh snore approximately 2 seconds long, shorter than that of northern leopard frog natural history: Produces skin secretion that is poisonous or unpleasant to many predators. The bright yellow or orange on the thighs serves as a warning to would-be predators to stay away. Feeds on a variety of insects, snails, worms, and spiders. Breeds April to May. Tadpoles transform by midsummer. similar species: Plains leopard frog has dorsolateral fold broken near groin and offset toward middle of back. Northern and southern leopard frogs lack double row of paired spots and bright yellow or orange on underside of thighs. Northern crawfish frog has mottled jaws, spots on back are crowded together, no white line along upper jaw.

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Mink frog

Lithobates septentrionalis range: MI, MN, WI size: 2–3 inches description: Medium green non-

climbing frog with dark brown circular spots or irregular blotches on back. Spots or lengthwise stripes on tops of legs. Upper jaw plain green with no markings. Dorsolateral fold may be complete, broken, or lacking altogether and ends at midback. Belly white to yellow with some mottling. Skin moist, smooth with musky, rotten onion, or minklike smell when handled. Male tympanum distinctly larger than eye. Female tympanum approximately same size as eye. Webbing on hind foot extends to tip of 5th toe. habitat: Lakes, ponds, bogs, slow-moving streams with abundant vegetation

voice: Series of 4 sharp raps, “cutcut-cut-cut,” similar to hitting 2 sticks together natural history: This northern, highly aquatic frog gets its name from the minklike smell it gives off when handled. It rarely gets far from water and may be seen sitting on water lilies or other aquatic vegetation. Feeds away from shoreline primarily on adult and larval aquatic insects. Breeds June to July. Tadpoles overwinter and transform in 1 to 2 years. similar species: Bronze and green frogs have dark crossbars on legs; webbing on hind foot extends halfway to tip of 2d toe; no musky, rotten onion, or minklike smell when handled; mottled upper jaw.

frog dorsolateral fold

tympanum (eardrum)

toad

webbing

parotoid glands cranial ridges

Drawings by W. James Hunter, adapted from Michigan Frogs, Toads, and Salamanders by James H. Harding and J. Alan Holman

warts

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b 14a 14b 15a 15b 16a 16b 17a 17b 18a 18b 19a 19b 20a 20b

1 or 2 large spades on heels of hind feet, distinct parotoid glands behind eyes, little webbing between toes of hind feet: 2 No spade on heels of hind feet, no parotoid glands behind eyes, weak to strong webbing between toes on hind feet: 7 Parotoid glands small, round, not easily seen; eye with vertical pupil; 1 large spade on heels of hind feet: 3 Parotoid glands large, eye with horizontal or round pupil, 1 large and 1 small spade on heels of hind feet: 4 Distinct raised area or boss between eyes; 1 short, wedge-shaped spade on each hind foot: plains spadefoot No raised area or boss between eyes; 1 long, sickle-shaped spade on each hind foot: eastern spadefoot Parotoid glands oblong and connected to cranial ridges, 3 or more warts on each dark spot on back, belly white with 1 dark spot on chest: 5 Parotoid glands kidney-shaped and separate from cranial ridges or connected by short spur, 1 or 2 warts on each of largest dark spots on back, belly and chest heavily mottled: American toad Cranial ridges between eyes come together and meet at snout to form raised knob: Great Plains toad Cranial ridges between eyes do not come together and meet at snout to form raised knob: 6 Irregular dark spots on back contain 1 to several warts, slightly less well developed cranial ridges: Woodhouse’s toad Dark spots on back arranged in pairs on either side of light stripe down middle of back, 3 or more warts on each dark spot on back: Fowler’s toad Fold of skin across back of head behind eyes, head small, tympanum absent: 8 No fold of skin across back of head behind eyes, head large, tympanum present: 9 Darker overall coloration, spotted or mottled belly, prominent marks on back: eastern narrowmouth toad Lighter overall coloration, unspotted belly, lacks prominent marks on back: Great Plains narrowmouth toad Tips of toes with disc-like toe pads: 10 Tips of toes without disc-like toe pads: 13 Less than 1 1/2 inches long, toe pads small, not distinct: 11 Usually more than 1 1/2 inches long, toe pads large, distinct: 12 Toes fully webbed, many warts on back, dark triangle between eyes: Blanchard’s cricket frog No webbing between toes, no warts on back, stripe on upper jaw, 3 dark stripes on back: boreal, midland, or upland chorus frog Distinct X-shaped mark on back, no warts on back, no white spot under eye: northern spring peeper No X-shaped mark on back, back with or without warts, white spot under eye: eastern or Cope’s gray treefrog Dorsolateral fold present: 14 Dorsolateral fold absent: bullfrog Dorsolateral fold ends at midback: 15 Dorsolateral fold extends length of back: 16 Dark crossbars on legs; webbing on hind foot extends halfway to tip of 2d toe; no musky, rotten onion, or minklike smell when handled; mottled upper jaw: bronze or green frog Spots or lengthwise stripes on legs, not bars; webbing on hind foot extends to tip of 5th toe; musky, rotten onion, or minklike smell when handled; upper jaw plain green: mink frog No dark mask through eye and tympanum, large dark spots on back: 17 Dark mask through eye and tympanum, no large dark spots on back: wood frog Mottled jaws, spots on back crowded together, no white line along upper jaw: northern crawfish frog Jaws not mottled, spots on back not crowded together, white line along upper jaw: 18 Paired squarish spots on back, bright yellow or orange on groin and under- side of thighs: pickerel frog Spots on back irregularly shaped and arranged, groin and underside of thighs white: 19 Light rings around spots on back, dorsolateral fold complete and extends to groin, snout usually with dark spot, tympanum usually unspotted: northern leopard frog No light rings around spots on back, snout with or without dark spot, single white spot on tympanum: 20 Dorsolateral fold broken near groin and offset toward middle of back, snout rounded usually with spot: plains leopard frog Dorsolateral fold complete and unbroken, snout pointed usually without spot: southern leopard frog

“Frogs and toads worldwide are endangered, and their biggest threats are human ignorance and indifference. It is also true— ask any kid—that frogs and toads are fascinating animals, once they are known. Terry VanDeWalle’s attractive and informative laminated guide to the frogs and toads of the Upper Midwest offers a bridge to a newfound knowing and understanding of these fine animals. It says: here are our frogs and toads—they are beautiful and valuable. But it also suggests, by extension, that you should now go out there and look—get a little muddy and rumpled—and discover again what you once knew as a kid.”—Michael J. Lannoo, editor, Amphibian Declines: The Conservation Status of United States Species

Frogs and toads have become canaries in the coal mine when it comes to conservation, as the discovery of malformed frogs has brought increased attention to global habitat loss, declining biodiversity, and environmental pollution. Midwestern species—already declining due to habitat loss from agriculture—have been greatly affected by this worldwide phenomenon. This colorful addition to Iowa’s series of laminated guides informs both amateur and professional herpetologists about twenty species of frogs and four species of toads most commonly found in the Upper Midwest states of Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, South Dakota, North Dakota, Kansas, Nebraska, Iowa, and Missouri. Terry VanDeWalle includes a complete description of each species along with information about range and habitat preferences, diet, types of calls, and breeding season. His comparisons of similar species and his comprehensive key, as well as superb photographs by Suzanne Collins, are helpful aids for identifying individuals in the field.

$9.95

Copyright © 2011 by the University of Iowa Press Printed in the U.S.A. www.uiowapress.org Manufactured by ProGuidez, Inc. Licensed under U.S. Patent N429 and 6,063,227; Mexican Model Reg. No. 10,020; Canadian Industrial Design Reg. No. 76,725