Basically, toad is a classification of frog. And here's another fun fact: There's no scientific distinction between a toad and a frog, according to the University of Michigan's Animal Diversity Web. In terms of scientific classification, both frogs and toads belong to the order Anura, which means "without a tail," according to Penn State University. Within the order Anura are several families of animals, including Ranidae, which are referred to as true frogs, and Bufonidae, which are referred to as true toads.
Other families of frogs and toads exist — for example, tree frogs are a different family of frogs than true frogs — but these are smaller groupings of species, and some are specific to certain regions of the world. While many frogs and toads look similar, there are some differences.
For example, frogs typically have long, strong hind legs that aid them in leaping, while toads have shorter hind legs more suitable for walking than hopping, according to Wildlife Preservation Canada. The difference in their legs also leads to a behavioral difference when approached by humans. Frogs will usually use their long, strong legs to leap into the water when approached, while toads are more likely to sit still and wait it out.
If toads do jump away, their jumps are shorter than frogs'. Another difference in their appearance is their eyes. Frogs usually have big, bulging eyes, while toads' eyes are more subtle in appearance.
Common frog in a UK pond. Common frog Rana temporaria with its mouth open. A common toad. Common toad sat in a clay flower pot. Common toad in the Lake District. Learn more about toads in the UK: Natterjack toad guide How do warm winters affect hibernating toads?
Even though the female frogs and toads are able to call, they do so infrequently. The males do most of the calling, and the majority of the singing is done at the breeding sites, because the main purpose of the call is to attract a mate. However, a different call may be used to stake out a territory, the frog or toad announcing his presence and in effect warning others away. The time of the year when frogs or toads begin their calling varies with species and depends on weather and temperature.
Some species may begin as early as late February, while others wait until some months after that. Calling can continue until August or even later, depending on the species. The call is produced in much the same manner as other animals produce sound—vocal chords vibrate as air passes over them. Unique to the frogs and toads, however, is the inflatable vocal sac possessed by most of them See Figure III With the mouth closed, these amphibians draw air through the nostrils and into the lungs.
The air then is forced from the lungs, and through openings usually located on the floor of the mouth, enters to inflate the sac s. To emit its call, the frog or toad then pushes the air from the sac s , forcing it over the larynx where the vocal chords are located. The sac is an effective resonator, like a sounding board on a stringed instrument. The sac itself, however, is not able to amplify the level of the call. As the air is expelled over the vocal chords and the call is completed, the sac deflates.
It often is seen as an area of wrinkles or folded skin on the throat or shoulders of some species. The calls produced by the various toads and frogs range from simple clicks to whistle- or bell-like sounds to a full, resonating deep croak.
Each species has its own distinctive call. It is recognized by the female of the species as the courtship ritual continues. For the call to meet its intended purposes, frogs and toads have developed an effective hearing system similar to that found in humans. In most species, the external eardrum, called the tympanum, is easily seen. The tympanum is protected by a thin layer of moist skin and is located behind the eye on each side of the head See Figure III Although there are seven members of this family residing in North America, only one occurs in Pennsylvania.
Spadefoot toads can be separated from the true toads by the single, horny, dark and spade-shaped tubercle on the under surface of each hind foot See Figure III This sharp-edged tubercle usually is referred to as a spade, and it gives this family its common name.
The spade is used effectively in digging rapidly into the soil. The skin of the spadefoots is not as rough or warty as that of the true toads. Eastern American toad — Anaxyrus americanus americanus Fowler's toad — Anaxyrus fowleri.
This family of toads is commonly called garden toads because of their habit of invading neighborhood gardens in search of insects, a favorite food. The toads are squat and plump and covered with dry, rough skin, which usually is dotted with warts. The true toads have no teeth on the upper jaw. Two tubercles are located on the underside of each hind foot. Enlarged parotoid glands located on each side of the head just above the neck secrete a poison that can cause inflammation of the mouth and throat and even death to a would-be attacker.
Only the hognose snake appears immune to these toxic secretions. Even humans can suffer severe irritation of the mucous membranes if they come in contact with these secretions. Northern cricket frog — Acris crepitans Spring peeper — Pseudacris crucifer Eastern gray treefrog — Hyta versicolor Mountain chorus frog — Pseudacris brachyphona Upland chorus frog — Pseudacris feriarum New Jersey chorus frog — Pseudacris kalmi Western chorus frog — Pseudacris triseriata.
The two small frogs of the genus Hyla spend most of their time in trees or small shrubs. These discs and their adhesive nature help these amphibians climb and perch in their arboreal homes.
The male usually sings his pleasant song while clinging to a small shrub or bush standing in or overhanging the water. The other members of this family are more terrestrial and seldom climb trees or shrubs. Their toepads are less developed. Eggs are laid in the water. In addition to the species illustrated and discussed in detail, two other closely-related members of this family occur in Pennsylvania.
Upland chorus frog Pseudacris feriarum feriarum and the New Jersey chorus frog Pseudacris feriarum kalmi —The upland chorus frog has been found in southcentral Pennsylvania to as far north as Lycoming County. The area in which sighted helps identify these two subspecies and to separate them from the western chorus frog which they resemble.
The New Jersey and upland chorus frogs are greenish gray to light brown or tan. Darker stripes divide the back. These stripes are more obvious on the New Jersey chorus frog than they are on the upland species, where they might be broken into rows of spots.
The upper lip is outlined with a narrow, white band. These small frogs can be found in a variety of habitats in grassy areas, either dry or wet, including swamps. Breeding occurs in shallow water from late winter to early summer. The call is similar to the western chorus frog. Bullfrog — Lithobates catesbeianus Northern green frog — Lithobates clamitans melanota Pickerel frog — Lithobates palustris Northern leopard frog — Lithobates pipiens Wood frog — Lithobates sylvaticus Southern leopard frog — Lithobates sphenocephalus utricularius.
These are the larger frogs, usually with a slim waist and long legs. The feet have pointed toes; extensive webbing connects the toes on the hind feet. Heavy folds of glandular skin, called dorsolateral folds, are located along the upper sides and can be an aid in separating certain species See Figure III The true frogs are voracious carnivores, consuming large amounts of spiders, insects and other invertebrates as well as small vertebrates.
If not in the water, they almost always are close to it where they quickly plunge in the event of danger. In addition to the species that are illustrated and discussed in detail, one other frog, which is included in the state's original herpetofauna, but now is endangered, should be included. Coastal Plain leopard frog Rana utricularia —This member of the true frog family is only rarely encountered. Much of its habitat has been destroyed, and its populations have suffered as a result.
It is included on the state's List of Endangered Species. The Coastal Plain leopard frog resides in fresh or brackish water and in summer ventures into fields and meadows to wander among moist vegetation. It has been sparsely recorded in its original range in extreme southeastern Pennsylvania. It is primarily nocturnal. Reaching two inches to perhaps four inches in length, this frog looks similar to the northern leopard frog.
The Coastal Plain leopard frog, however, has a whitish spot on the center of the eardrum, or tympanum, which the northern leopard frog does not have. Narrow dorsolateral ridges extend to the groin. The ridges are light-colored and are separated by dark spots. This leopard frog is greenish to brown over the back and sides. The legs are marked with dark spots or bars. The upper jaw is margined with a light line and the head is long and pointed.
Breeding occurs from March to June when the female seeks shallow water in which she lays up to 5, eggs. The eggs hatch about two weeks later and transform by summer. Scaphiopus holbrookii holbrookii. General characteristics. The eastern spadefoot toad is similar in appearance to the true toads.
However, its skin is smooth and covered with minute tubercles, unlike true toads, which have rough, warty skin. It is the only spadefoot east of the Mississippi River. The eastern spadefoot has a built-in repellent, as do all other amphibians, including toads. Skin secretions emitted from glands can cause irritation, especially to mucous membranes, even on humans.
The secretions can be fatal to certain predators. The primary key to identifying the eastern spadefoot toad is the hard sickle-shaped spade on each hind foot. This horny, sharp-edged tubercle can be found at the base of the shortest toe; there is only one spade. On the true toads, each foot has two enlarged tubercles, only one of which is sometimes hardened and spade-like See Figure III Also, unlike true toads, the spadefoot toad has teeth on the upper jaw.
The skin of the spadefoot toad is relatively smooth and covered on the back and sides with tiny, scattered tubercles. The body color can range through various shades of brown to yellowish or grayish to nearly black.
The lighter shades frequently are mottled with darker pigments. There may be two light lines starting at the eye and continuing down the back. These lines, if present, are irregularly shaped and yellowish. Sometimes a light line also runs along each side of the body. The underside of the eastern spadefoot is white to grayish and unmarked.
The tympanum, or external eardrum, is distinct and obvious. The parotoid glands, on the other hand, are inconspicuous and appear to be absent. The eyes are prominent, elevated well above the upper surface of the head; the iris is golden.
The pupil is black and vertically shaped, not horizontal as in the case of the toads. In Pennsylvania, the eastern spadefoot toad resides in a split range. Populations are found in southcentral Pennsylvania in the Susquehanna River Valley from the Maryland border to the northcentral part of the state. The range becomes more narrow as it moves northward.
The spadefoot also occurs along the extreme eastern edge of the state, beginning in the southeast corner where it follows the Delaware River Valley north to Monroe County. Its range extends into parts of New England and as far south as central Florida. Its western boundary is Missouri. The eastern spadefoot toad especially likes sand, gravel or loose loam into which it can quickly burrow for protection.
In the eastern United States, this species may be at home in forested or brushy areas, even cultivated land. However, other species of the spadefoot in more arid areas of this country usually are restricted to the preferred sandy soils more common to those areas. The spadefoot seeks protection from adverse weather and predators by digging furiously into the loose soil. Using a backward digging movement and the spade on its hind legs as a digging tool, the spadefoot can be inches underground in a very short time.
The burrow is dug nearly vertically five to 10 inches deep. The spadefoot can spend weeks, even months, underground, coming out only on warm, damp evenings to survey its surroundings or seek a meal. If it has time only to dig a very shallow hole, or if it wants to sit near the mouth of a deeper burrow, the spadefoot is able to assume a position that fills the opening. Facing outward, the spadefoot rests its chin on the front feet with the head bent downward.
Tucking its feet in close and with eyes shut, the spadefoot expands its lungs to cause its sides to puff out, filling the passageway. Under these circumstances, the spadefoot is difficult to detect or grab, and closing off the entrance, it prevents any intruder from getting in behind.
The eastern spadefoot toad normally is a spring breeder, but mating can occur as late as September. Calling starts from the time the spadefoot leaves hibernation in March, and the female responds to the male's song after a torrential rain; actual breeding has to wait until sufficient rainfall creates a temporary pool. Most of the breeding takes place in such pools, rather than in permanent ponds or streams.
Temporary pools can be rain-filled depressions in the ground, ditches or impermanent marshes. The spadefoot toad is an explosive and opportunistic breeder. Females are attracted to the male who has been calling from a rain-created pool.
The male grasps the female around the waist and fertilizes the eggs as they are laid. The eggs are deposited in short strings of gelatinous bands and are attached to vegetation standing in the water.
She lays about 2, eggs, a number considered unusually low for an amphibian using temporary pools for breeding. Thus, survival of the eggs and tadpoles is critical and could affect the population of the species in a particular area.
The process of egg development and transformation into a young spadefoot toad must be completed before the pool of water dries up. This accelerated cycle sometimes can be completed in as little as two weeks. Normally, the eggs hatch in two short days with transformation occurring several weeks later.
The tadpoles are dark in color with a narrow spotted tail. The tadpole leaves the water as transformation begins and while the tail is still quite long. If it did not, the larva could drown because it would not be able to move about properly with the added weight and length of the tail.
The eastern spadefoot toad may begin calling from the burrow even before it has completely vacated its winter home. Later, as rainfall fills nearby ditches and other low areas, the male spadefoot begins to call from the surface of the water.
The song is a coarse, nasal, low-pitched grunt that seems to burst from the vocal sac. The call is short, but repeated at about two-second intervals. It has been described as sounding like the cry of a young crow. It carries well, up to a half-mile. The throat sac where the call originates is a white bubble three times the size of the head when inflated. Normally, the spadefoot toad does not venture far from its burrow in search of food. Flies, other insects and spiders are the mainstay of its diet.
Bufo americanus americanus. The eastern American toad, closely related to Fowler's toad, is more widely distributed in Pennsylvania. It can be confused with Fowler's toad, although there are several characteristics separating the two. They are noted here and in the description of Fowler's toad.
The eastern American toad, however, can tolerate colder temperatures and thus goes into hibernation a bit later than Fowler's and emerges a few weeks earlier in the spring. The eastern American toad is primarily nocturnal and spends most of its day sheltered among piles of leaves or burrowed under loose rocks.
So even though it is an abundant toad throughout most of its range, its nighttime habits prevent it from being seen very often. This is the common "hoptoad," so-called because of its "hopping" in moving from one area to another, rather than "leaping," as frogs do.
Characteristic of other toads, toxic secretions from skin glands can irritate mucuous membranes. People do not, however, get skin warts from this or any other toad. Various patterns or patches in light colors, usually buff or yellowish, mark the eastern American toad.
These patterns occur over a background color that usually is brown, but that also can be olive to brick red. In some specimens, a light stripe runs down the center of the back.
The forward part of the belly, or abdomen, and the chest are spotted, compared to the plain underparts on Fowler's toad. Dark spots in brown or black range over the back. Each of these larger spots contains only one or two warts; Fowler's has three warts in each. These warts are red, yellow, orange or sometimes dark brown. The warts on each thigh are enlarged, bigger than on Fowler's toad. The parotoid gland located behind the eye is more kidney-shaped than the elongated gland of the Fowler's toad See Figure III On the eastern American toad, this gland does not touch the cranial crest a bony ridge.
The eyes of the eastern American toad are elevated well above the head. The pupils are horizontally shaped and black; the iris is golden on this toad, compared to Fowler's bright yellow. Distributed statewide in Pennsylvania, the eastern American toad is a wide-ranging amphibian residing east of the Rocky Mountains. It is found from the warm climes of Louisiana to the cold of the Labrador Peninsula in Canada. This amphibian has adapted to a variety of habitats and can be found in populated areas to remote wilderness regions, from well-manicured lawns to grassy fields and heavily forested, often rocky mountains.
It has two requisites for suitable habitat over most anything else: The area must be moist and include an area of shallow water for breeding, and the area must have an abundance of insects. It is often seen foraging over plowed fields where a variety of invertebrates has been disturbed as the land is prepared for agriculture. It is a friend of farmers and gardeners alike. The eastern American toad, though more tolerant of colder temperatures than Fowler's, seeks protection from the winter before the first frost hits.
It hibernates in the ground where it burrows into loose soil. The eastern American emerges from hibernation and breeds before Fowler's toad, but after the common frogs such as the leopard, pickerel frog and wood frog. Mating occurs from March until July. Shallow water is required for breeding, even if it is only a temporarily filled ditch or rain pool.
If a stream is selected, a slower-moving section or pool provides suitable breeding habitat. The male arrives first at the breeding pond or pool. Emerging from hibernation in the spring, he travels at night to reach the water.
Here, from the shallows, the male American toad begins to call his mate. Eggs are released and fertilized as the male and female toads float together on the surface of the water. The eggs are small and may number from 4, to 20, They are released in long, curling strings, usually a double strand encased in a protective jelly-like tube.
They may stick to vegetation, or sometimes simply float downward until they rest on the bottom. Depending on the temperature of the water, the eggs hatch in as little as three days or up to nearly two weeks.
Breaking free of the small eggs, the black tadpoles begin to breathe using gills which at first are located externally. As the tadpoles develop, however, these gills become encased in a flap of skin. They remain in this larval stage a little less than two months, metamorphosing in mid-summer. During transformation, the back legs appear first, then 10 to 14 days later the front legs suddenly appear.
Common toads are found all over Britain, and spend more time on dry land than frogs and may remain in one area all summer. The Natterjack has a very restricted range and is only found at a few coastal dune, saltmarsh and inland heath sites in Britain.
By mid-October, most toads and toadlets have retreated to dry banks, holes used by small mammals, compost heaps, amongst dead wood, under garden buildings and other places offering shelter. They will stay in these sites through the winter, but may take advantage of mild patches of weather to forage. Wildlife World sells specifically designed Toad and Frog Houses called Frogilos which offer a safe retreat away from predators.
In the spring, males are usually the first to emerge from their over-wintering sites and make their way to their breeding ponds. Toads have a phenomenal homing instinct and will travel through all sorts of obstacles to reach the breeding site.
This scenario is often fatal to the female toad, who is drowned in the furore. Toad eggs are encased in jelly and laid over a 24hr period in a string around submerged weeds. A string of up to 7m in length can contain over eggs.
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