Amphibians of North Carolina

Scientific Name:	Common Name:		Family (Alpha):

NC Records
Bufonidae Members:
Anaxyrus americanus - American Toad

Taxonomy

Class: Amphibia

Order: Anura

Family: Bufonidae

Synonym: Bufo americanus


Taxonomic Comments: Three subspecies of the American Toad have been recognized by some authorities that reflect phenotypic variation in color pattern, spotting, the extent of ventral pigmentation, and size (Dodd 2013). These include the wide-ranging Eastern American Toad (A. a. americanus), a smaller and more reddish Dwarf American Toad (A. a. charlesmithi) that occurs from southwestern Indiana and southern Illinois to Arkansas, eastern Oklahoma, and northeastern Texas, and a far northern Hudson Bay Toad (A. a. copei) that is found in the Hudson Bay region and is boldly marked and stockier than the others. Recent treatments do not recognize A. a. copei as a valid taxon, and molecular analyses do not strongly support the recognition of A. a. charlesmithi, with bootstrap values < 75% for mtDNA analyses (Masta et al. 2002). Other analyses using nuclear DNA have yet to be conducted on these forms. Here, we do not recognize subspecies and treat the American Toad (A. americanus) as a monotypic, geographically variable species. The American Toad hybridizes with several other species of toads in areas of contact. This reflects the fact that males will often amplex heterospecific females at sites where two species are syntopic and breed at the same time of the year (Dodd 2013). In North Carolina this appears to happen on rare occasion with both Fowler's Toad and the Southern Toad (Beane et al. 2010, Dodd 2013).
Species Comments: This widespread and common species has been the subject of numerous studies that are summarized by Dodd (2013).

Identification

Description: Anaxyrus americanus is a medium to large toad with most adults varying from around 50-90 mm SUL (maximum = 155 mm). The average adult size can vary substantially between regional populations, and females in local populations average larger than the males. Beane et al. (2010) reported a size range of 50-107 mm SUL for specimens from North Carolina and vicinity, and noted that populations in the mountains are larger on average than those farther east. Amplexing males that Wilbur et al. (1978) collected from a population in Chatham Co. averaged 11 mm smaller than their mates (53 versus 64 mm SUL). The dorsal ground color can vary from various earth tones (gray, olive brown, or a rich brown) to brick red. The dorsal patterning is also variable, and ranges from individuals that are rather uniformly colored to others that are mottled with varying shades of cream and earth tone colors. Individuals sometimes have a complete or partial mid-dorsal stripe that is lighter than the ground color and extends from near the snout to the urostyle. The width of the stripe in uneven along its length, which often gives it a weakly jagged appearance. The skin is covered with small circular bumps and larger warts, and there is a prominent oblong parotoid gland behind each eye. The dorsal and dorsolateral regions have a series of small blackish spots -- often with cream-colored borders -- that typically have one large wart per spot. The lower half of each hind limb (the tibiofibula or calf region) also has a set of prominent large warts. The belly is white and often has scattered dark spots towards the front. The cranial crests are prominent on the adults, with the postorbital (transverse) branch of each cranial crest extending in front of the parotoid gland. A small gap may occur between the postorbital branch and the parotoid gland, or the two may be connected by a short spur. Adult males have a dark vocal sac and throat, and develop nuptial pads on the thumbs during the breeding season. The juveniles are colored like the adults, but have smoother skin and less prominent cranial crests. The American Toad closely resembles both Fowler's Toad and the Southern Toad. Fowler's Toads typically have three or more warts in each of the largest dorsolateral spots and less prominent cranial crests. The transverse branch of each crest touches the front of the parotoid gland, rather than being separated by a gap or connecting spur. The mid-dorsal stripe is also of a uniform width versus irregular in width in the American Toad. The Southern Toad is best separated by geographic range and the presence of large knobs on its prominent cranial crests. The American Toad sometimes hybridizes with both Fowler's Toad and the Southern Toad and specimens are occasionally found that are difficult to assign to species (Beane et al. 2010, Dodd 2013). The tadpoles have small eyes, are dark brown to black above, and have pigmented throats. The belly has extensive areas of gold or copper spotting, while the tail is short and bicolored with fins that are cloudy transparent in coloration (Dodd 2013). During the day the larvae frequently aggregate in large groups in shallow water along the margins of ponds.
Vocalizations: The advertisement call is a high-pitched trill that typically last around 6–12 seconds (range = 1-19 seconds). A given male will often pause for 20-30 seconds or more before issuing another call. Call characteristics are temperature-dependent and the pulse rate is positively correlated with the water temperature near a calling male (Dodd 2013, Zweifel 1968). In addition to the advertisement call, males have a release call that consists of a series of short, vibrating chirps that signal for a male that inadvertently amplexes another male to dismount. Males may also make an amplexus call that consists of a series of clicking sounds that are emitted when clasping females (Price and Meyer 1979).
Technical Reference: Dodd (2013)
Online Photos: Google iNaturalist
Observation Methods: The juveniles and adults are most active at night and are frequently found on roads during or following rains. Individuals sometimes feed around building lights at night, and the calling adults can be heard from long distances.

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AmphibiaWeb Account

Distribution in North Carolina

Distribution Comments: This is a wide-ranging species that is restricted to eastern North America. The range in Canada extends from southern Labrador westward across Quebec through most of Ontario to southeastern Manitoba (Dodd 2013). In the US, populations have been found from the New England states westward through the Great Lakes region to the eastern Dakotas, then southward through much of the eastern US to southeastern Texas, northern and southeastern Louisiana, central and northwest Mississippi, northern Alabama, northern Georgia, and northwestern South Carolina. Populations in North Carolina are largely restricted to the western mountains, the Piedmont, and the extreme northeastern section of the Coastal Plain where an apparent geographic disjunct is present (Beane et al. 2010). We have very few records, if any, from the sandy, fire-prone sandhills, flatwoods, and savannas that once dominated the Outer Coastal Plain. Populations in the mountains are most common at lower elevations, but have been found at Mt. Mitchell and other high-elevation sites.
Distribution Reference: Beane et al. (2010), Dodd (2013)
County Map: Clicking on a county returns the records for the species in that county.


GBIF Global Distribution

Key Habitat Requirements

Habitat: The American Toad occurs in a variety of habitats throughout its range, but shows a general preference for open, deciduous forests. Local populations often use grasslands in the upper Midwest, and can be found in a variety of disturbed settings throughout the range so long as suitable breeding sites are nearby. Examples include conifer plantations, cut-over lands, wildlife clearings, and agricultural and urban landscapes (Dodd 2013).

In North Carolina, A. americanus is mostly restricted to the Piedmont and Blue Ridge Mountains where it is generally affiliated with deciduous forests. It occurs in both upland and bottomland hardwoods, as well as both closed canopy forests and open woodlands and edges. Populations in the Blue Ridge are mostly found in the lower valleys where breeding habitats are more prevalent, but this species has been found as high as Mt. Mitchell. While stands of hardwoods were probably the original main habitat used by this species, it is now common within semi-wooded suburban areas. In some urban areas it can be found locally where there is little or no tree cover, provided there is adequate cover and moisture at ground level and suitable breeding sites nearby. Open, sparsely vegetated areas with little cover are largely unoccupied by this species. Sites with friable soils in which to dig, abundant coarse woody debris for shelter, and mesic conditions appear to provide optimal microhabitats for the juveniles and adults (Dodd 2013).

The adults breed in habitats that range from small seasonal ponds to permanent large wetlands with fishes. The larvae have chemical defenses against fishes, so this species often uses permanent habitats with fishes -- particularly where there are vegetated shallows or other microhabitats that provide a degree a spatial segregation from these and other predators. The adults mostly use standing water habitats, but in some areas will use small, sluggish streams and the backwaters of rivers. The breeding habitats range from very small sites such as flooded tire ruts and large puddles in roads, to borrow pits, farm ponds, and large reservoirs and lakes. Examples of natural lentic habitats that are used include vernal ponds, sinkhole ponds, marshes, fens, bogs, swamps, beaver ponds and flooded wet meadows (Dodd 2013).

Environmental and Physiological Tolerances: The American Toad appears to be very cold tolerant, mostly because of its ability to burrow deep within friable soils. It ranges as far north as Hudson Bay and Labrador (Conant and Collins 1991) and occurs throughout the Blue Ridge Mountains in North Carolina, including occasionally at high-elevation sites. Conversely, this species may not be tolerant of extreme temperatures, being generally absent from the Atlantic and Gulf Coastal Plains. The tiny metamorphs appear to be highly vulnerable to excessive heat and dryness. Other factors that may preclude its presence in the Coastal Plain include the sensitivity of larvae to acidic waters and an inability to cope with frequent fires. The eggs and larvae are sensitive to acidic water, but local populations vary in their tolerance of acidic conditions (Dodd 2013, Freda 1986, Freda et al. 1991). Freda and McDonald (1993) surveyed ponds in Ontario and found that survivorship of larval American Toads was often reduced in ponds with a pH < 4.8. Sites with pH’s < 4.2 are often lethal for eggs.

Biotic Relationships: The larvae produce skin toxins that make them unpalatable to potential predators. The degree of unpalatability varies depending on the predator and stage of development of the larvae (Brodie et al. 1978, Brodie and Formanowicz 1987), and the skin toxins rarely provide 100% protection from fishes, newts, ambystomatid larvae, odonates and other aquatic predators (Dodd 2013, Holomuzki 1995, Kats et al. 1988, Kruse and Stone 1984, Relyea 2001a, Smith et al. 1999, 2016, Voris and Bacon 1966, Walters, 1975). The larvae often breed in permanent ponds with fish, and in some cases fish may enhance the survival of larvae by preying on invertebrate predators such as dragonfly larvae (Walston and Mullin 2007).

In addition to chemical defenses, the larvae have evolved behavioral adaptations to predators. In at least some populations larvae will reduce their swimming activity in the presence of fish and dragonfly larvae (Holomuzki 1995, Relyea 2001b), but in other populations this does not appear to be the case (Dodd 2013). Larvae also are capable to detecting certain predators using chemical cues. When chemicals from predators such as odonates and centrarchid fishes are detected, the tadpoles will reduce their movements or swim away from areas where chemicals are present (Gallie et al. 2001). In addition, larvae can recognize cues released from injured conspecifics and will avoid an area where injured tadpoles occur (Petranka 1989). The adults have also evolved adaptive behaviors to avoid predators. Wood Frog tadpoles in western North Carolina are highly efficient predators on both the eggs and hatchlings of American Toads. The adult toads almost never breed in ponds with Wood Frog tadpoles, and actively seek out ponds that lack these predators (Petranka et al. 1994, Petranka and Holbrook 2006).

The juveniles and adults use chemical defenses and will secrete toxins from the parotoid glands and warts if molested. They have other behavioral defenses such as inflating the body, remaining immobile as a predator approaches, fleeing, and tucking the chin downward toward the pectoral region (Dodd 2013). These defenses work in some cases, but many individuals succumb to predators. Small juveniles that are moving away from the breeding sites are taken by both invertebrate and vertebrate predators. Devore and Maerz (2014) found that spiders were significant predators on the small juveniles. Dodd (2013) listed a variety of known vertebrate predators, including the Eastern Hog-Nosed Snake (Heterodon platirhinos), Eastern Garter Snake (Thamnophis s. sirtalis), Northern Watersnake (Nerodia s. sipedon), Plain-Bellied Watersnake (N. erythrogaster), Queensnake (Regina septemvittata) and Snapping Turtle (Chelydra serpentina). In addition, spiders (Nyffeler and Altig 2020), skunks, raccoons, and numerous birds prey of the juveniles and adults.

See also Habitat Account for General Hardwood Forests

Life History and Autecology

Breeding and Courtship: The males begin moving to breeding sites soon after they emerge from winter hibernation. Their long, continuous trills can be heard during the day, but singing activity generally increases in the early evening hours. The females typically arrive at the breeding sites a few days to a week after the males begin singing (AmphibiaWeb 2021). The seasonal time of arrival progressively increases from the southern and coastal portions of the range to more northern and mountainous regions. Breeding often begins in mid-January and February in Alabama and Louisiana (Dundee and Rossman 1989, Mount 1975). Breeding occurs between late-January through early April in Tennessee (Niemiller and Reynolds 2011), in March and April in West Virginia and Kentucky (Barbour 1971, Green and Pauley 1987) in mid-April to mid May in Maine (Hunter et al. 1992), and in early May to mid June in Minnesota (Oldfield and Moriarty 1994). Breeding typically occurs from late-February through March in the Piedmont of North Carolina, with populations in the mountains generally lagging behind by a few weeks depending on elevation. The peak of breeding activity usually lasts only about two weeks at a given location.

The males often greatly outnumber females at a breeding site at any given moment, in part because they tend to stay longer at a breeding sites than the females and reach sexual maturity at an earlier age (Christein and Taylor 1978, Dodd 2013, Forester and Thompson 1998). In many populations females tend to select the larger males as mates (Fairchild 1984, Gatz 1981a) and often use call characteristics when picking a mate (Dodd 2013). Although females tend to be selective with regard to male size, there is little evidence that larger males produce genetically superior offspring (Howard et al. 1994, Kruse 1981).

Males attempt to find mates both by calling and actively searching for females. Calling typically occurs from the shoreline or in shallow water. Although many males call for females, others apparently do not and simply try to intercept females before they amplex with calling males. Howard and Young (1998) found that only 50% of the males at an Indiana breeding site called, while Gatz (1981a) found that non-calling males were almost as likely to find mates as calling males. Forester and Thompson (1998) observed that only a few males actively called at their study site in Maryland on any given night. Most males that were in the pond swam around and either tried to intercept arriving females or dislodge amplexed males. Other relatively small males that likely had unattractive call characteristics sat on land at the pond edge and intercepted arriving females. About 70% of the arriving females were amplexed by these smaller terrestrial males. If a male is inadvertently amplexed by another male, the male will issue a warning chirp and vibrate his body which triggers the amplexing male to decouple.

Anaxyrus americanus tends to be an explosive breeder, with most mating and egg-laying in a local population occurring on only a small number of nights during the breeding season. The males may call for several weeks at a local breeding site, but females tend to arrive and mate on only a few nights. There are often only 2-4 major breeding bouts during the entire breeding season, with pauses in mating and egg-laying between bouts (Dodd 2013). Amplexus is either axillary or supra-axillary, and the pair stays together until egg laying is completed. Rival males may attempt to displace amplexed males, but are almost always unsuccessful (Howard et al. 1994).

Reproductive Mode: Each female deposits two long strings of eggs in shallow water and the male fertilizes these as they protrude from the female's cloaca. The eggs are typically laid either on the bottom substrate or draped on branches, aquatic vegetation, or other support structures around the margins of wetlands. Clutch size increases with female size, with the estimated number of eggs that are laid varying from 1,700 to 20,000 per female. Thus, the biotic potential of this species is enormous. Some specific records for clutch sizes that were reported by Dodd (2013) include a mean of 4,701 (range 1,840 to 13,982) in Arkansas (Trauth et al. 1990), 3,341 in Louisiana (Dundee and Rossman 1989), 2,200–6,500 in Michigan (Brockelman 1968), 1,767–9,765 in Indiana (Howard 1988), and 3,929–15,835 eggs in Massachusetts (Miller 1909a). Hatching typically occurs within 3-7 days after the eggs are laid, but varies depending on the prevailing water temperatures and weather patterns.

Aquatic Life History: The tadpoles filter-feed on detritus, algae, and other food that is suspended in the water column. They also eat filamentous algae, blue-green algae, periphyton, diatoms, soft tissues from vascular plants, crustacean eggs, carrion, and fecal material (Dodd 2013). Because of the large clutch sizes of this species and high hatching success, small ponds and other breeding sites often contain tens of thousands of hatchlings and young larvae. On sunny days the tadpoles tend to concentrate at very high densities in relatively warm water near the shoreline, then disperse and scatter into deeper waters at night. Petranka (1989a), for example, estimated that local tadpole densities along the margin of a pond in the Piedmont of North Carolina ranged from 12,412-29,725 tadpoles/m2 of pond bottom.

Large aggregates typically form on sunny days when the shallows are several degrees warmer than the deeper portions of ponds (Beiswenger 1977). Crowding in the shallows may function to increase the feeding efficiency of individual larvae via group feeding that stirs up bottom debris and enhances filter-feeding (Beiswenger 1975) . It may also enhance the effectiveness of chemical defenses against predators by reinforcement, and allow larvae to grow more rapidly since growth rates are temperature dependent (Dodd 2013). The black bodies of tadpoles act as solar sinks, and tightly packed groups have the potential to raise ambient water temperatures in very shallow water.

Aggregating larvae sometimes remain relatively stationary where they scavenge and feed on detritus and periphyton. They also actively school along shorelines where they either stream along while not feeding, or move in slow, dense clusters that stir up food particles (Beiswenger 1975, Dodd 2013). The tadpoles are capable of recognizing siblings -- probably by using chemical cues -- and will differentially associate with siblings in both the field and laboratory (Waldman and Adler 1979, Waldman, 1981, 1982). The exact function of aggregating with kin is not fully understood. Petranka (1989) found that larvae respond to alarm chemicals that are released by injured conspecifics by rapidly fleeing from areas where there is an injured tadpole (Petranka 1989). One possible benefit is that individuals that are attacked by predators would emit alarm chemicals that warn siblings of a predator's presence (Waldman 1982).

Competition for food resources likely occurs in many situations where larvae reach high densities. Crowding can have several adverse effects that play a role in density-dependent population regulation. At higher densities, larvae grow slower, have prolonged larval periods, are smaller at metamorphosis, and are less likely to survive to metamorphosis (Brockelman 1969, Wilbur 1977b, Wilbur and Fauth 1990). The larvae undoubtedly compete with the tadpoles of other species that share breeding ponds and have similar feeding modes (Alford 1989a, 1989b, Alford and Wilbur 1985). The intensity of both intra- and interspecific competition is mediated by predators that can either reduce the density of conspecifics or selectively reduce the numbers of interspecific competitors (Alford 1989a, Wilbur and Fauth 1990).

The larval period is relatively brief and typically last 5-9 weeks depending on ambient conditions. Reported values include 37–52 days in Michigan (Brockelman 1968), 41–66 days in New York (Wright 1914), and 42–70 days in Indiana (Minton 2001). The newly metamorphosed froglets are very small, with most varying from around 6-12 mm SUL.

Despite having toxic skin secretions and using chemical cues to detect predators, the larvae are preyed upon by numerous species such as predaceous diving beetles, odonate larvae, crayfishes, ambystomatid salamander larvae, and the Eastern Newt (Dodd 2013). These, in conjunction with competition, diseases and parasites take their toll. Survival to metamorphosis is poorly documented in nature, but like most pond-breeding amphibians is probably less than 10%. Seale (1980) noted that none of the estimated 200,000 tadpoles that hatched in her study pond in Missouri survived to metamorphose. Predation by Tiger Salamander larvae appeared to be the primary source of mortality, and most larvae were eliminated when very young. Premature pond drying can result in complete mortality in some years for populations that use seasonal ponds. Thus, reproduction appears to often be episodic, with occasional years that produce bumper crops of froglets.

Terrestrial Life History: The juveniles and adults often move relatively long distances from the breeding sites. They commonly have been found > 400 m from the nearest breeding site, and in some instances a kilometer or more away (Dodd 2013). Females in Maryland dispersed a minimum of 250 m and up to 1000 m from their breeding site, with 97% moving more than 400 m (Forester et al. 2006).

The tiny froglets disperse away from the breeding ponds into the surrounding uplands shortly after metamorphosing. The juveniles show a preference for forest habitats (e.g., Walston and Mullin 2008), and experimental studies (Rothermel 2004, Rothermel and Semlitsch 2002) suggest that the metamorphs often suffer high mortality when moving across open habitats such as pastures and old fields. This is presumably due to physiological stress from being exposed to the hotter and drier conditions of open sites.

After dispersing from the breeding sites, individuals establish home ranges where they devote their summer activities to feeding and avoiding predators. Forester et al. (2006) found that the home ranges of adult females in Maryland averaged 717 m2, with individuals shifting to several local activity centers during the warmer months that ranged from 30 to 100 m2 each. Most males typically mature at the end of their second summer and breed the following spring, while most females require an additional year to lay their first clutch. The adults rarely live beyond four or five years, which suggests that most only breed once or twice during the lifetime (Acker et al. 1986, Green and Pauley 1987, Kalb and Zug 1990, Meshaka et al. 2017).

The juveniles and adults are most active during periods of rainy weather, and tend to feed and move locally when conditions are warm and moist (Ewert 1969, Forester et al. 2006). During hot, dry spells they either burrow in the soil or seek out other moist refuges beneath logs and rocks or in leaf litter. Individuals can stay hydrated by directly taking in water across their skin when resting on moist substrates (Walker and Whitford 1970). Individuals mostly forage at night, with peak activity typically occurring within the first few hours after dark. A secondary peak sometimes occurs around dawn (Dodd 2013). Individuals are occasionally seen during the day on overcast days or during heavy rainfall events.

American Toads feed on invertebrates that they either ambush or actively seek out as they hop about. The numerous dietary studies of this species (AmphibiaWeb 2021, Dodd 2013) suggest that they are generalist, gape-limited predators that will take any palatable prey that they can catch with their protractible tongue. The juveniles feed on small invertebrates, including tiny prey such as springtails, mites, parasitoid wasps and ants, while the large juveniles and adults consume a greater variety of invertebrates that reflects their larger gape. Dodd (2013) noted that some of the commonly consumed prey among 11 dietary studies included ants, beetles, grasshoppers, fly larvae, butterflies, moths, and wasps, along with isopods, millipedes, spiders, snails, slugs and many other taxa.

American Toads are active on the ground surface during the warmer months of the year. Individuals gradually resume their activity with the spring warm-up, and in some areas may be active on the ground surface for a month or more before moving to the breeding sites to mate. With rare exception, the juveniles and adults overwinter on land and begin to move underground with the onset of cold weather in the autumn. This species lacks cryoprotectants and has to stay below the frost line to avoid winter kill (Dodd 2013, Holzwart and Hall 1984). Individuals are capable of digging deep burrows where the soils are sandy or friable. Ewert (1969), for example, found that toads in Minnesota burrowed 12-58 cm below ground to avoid winterkill. Those in North Carolina presumably burrow to much shallower depths during the winter.

In North Carolina individuals in the Piedmont generally begin to become surface active in February, with increasing surface activity from March onward. Breeding is usually well underway by late-February through March and individuals often remain active on the surface until well into November. Populations in the mountains generally lag behind in the spring by a few weeks depending on elevation, and begin moving underground in October through early November depending on the elevation and site conditions.

General Ecology

Population Ecology: Factors that regulate local populations are poorly known. Sexual competition among males for limited females may play a part, and density-dependent growth and survival during the larval stage is undoubtedly important. The population dynamics of the juvenile stage are poorly understood, but there is no evidence that the terrestrial stages are territorial.

Community Ecology: Interactions of American Toad larvae with other community members have been addressed by numerous researchers using experimental communities that were established in cattle tanks, field enclosures, and laboratory aquaria (reviewed by Dodd 2013). These have involved experimentally manipulating factors such as the density and composition of competitors, the types and densities of predators, food levels, and the seasonal phenologies of competitors and predators. Larval growth rates, survival, and size at metamorphosis are typically used as response variables. These studies show that A. americanus often competes for food resources with other anuran larvae such as Scaphiopus holbrookii or Lithobates sphenocephalus that share breeding ponds, particularly when predators are absent or at low densities (e.g., Alford 1989a, 1989b, Alford and Wilbur 1985, Dodd 2013, Wilbur 1987). Predators such as the Eastern Newt can mediate the intensity and outcome of competitive interactions, and seasonal phenology can also affect the outcome of competitive interactions. The extent to which these results apply to more complex natural breeding sites is poorly resolved.

Adverse Environmental Impacts

Habitat Fragmentation: Populations of the American Toad are often found in fragmented habitats that contain both forested and agricultural or urban lands. However, studies by Rothermel (2004) and Rothermel and Semlitsch (2002) suggest that the tiny juveniles that disperse away from breeding sites often suffer high mortality when moving across open habitats such as pastures and old fields that are relatively hot and dry. Survival was inversely related to the distance from the nearest forest, which indicates the need for connectivity between breeding sites and forested habitats. Many ponds that are in open habitats and far removed from forest habitats may function as ecological traps where the adults use them as breeding sites, but few if any juveniles survival the long journey to moist, forested retreats.

Effects of Pollution: Dodd (2013) provides a comprehensive summary of the known effects of pesticides and pollutants on A. americanus. Pesticides are a concern since the juveniles and adults can directly absorb water through their skin and pick up pesticides in agricultural fields. The commercial weedkiller Roundup™ is extremely toxic to toad tadpoles at ecologically relevant concentrations (Relyea, 2005a, 2005b), mostly due to the surfactant that is used in the product. The widely used fungicide Mancozeb (one ethylenebisdithiocarbamate) is also very toxic to toads at 0.08 mg/L or greater (Harris et al. 2000).

Effects of Introduced Species/Induced Increases of Native Species: Devore and Maerz (2014) found that an invasive grass (Microstegium vimineum) that is widespread in North Carolina can indirectly cause higher mortality in young toads. Areas with dense growths of Microstegeum supported relatively high densities of lycopsid spiders which preyed upon the small toads. Other studies have shown that invasive aquatic plants such as Purple Loosestrife (Lythrum salicaria) that have high concentrations of soluble phenolics in their leaves can greatly reduce larval survival to metamorphosis (Cohen et al. 2012, Maerz et al. 2005).

Status in North Carolina

NHP State Rank: S5

Global Rank: G5

Environmental Threats: The greatest threats appear to be from the loss of wetlands, severe habitat fragmentation, and exposure to pesticides and pollutants. Countless thousands of toads are killed on roads annually in North Carolina, and ever increasing traffic volume adds to the problem.

Status Comments: This species appears to be secure within the state. Despite the widespread loss of natural habitats, American Toads have adapted well to using constructed farm ponds, reservoirs, and water features in urban neighborhoods.

Stewardship: Robust local populations are best maintained by having a cluster of breeding sites close to nearby forests. Habitat fragmentation can impact local populations since the tiny metamorphs can die when dispersing from ponds across relatively hot and dry open fields. Juvenile survival would likely be enhanced by having wooded corridors that allow dispersal from ponds that are in fields or other open habitats to nearby forests.

Recording Gallery for Anaxyrus americanus - American Toad
	2022-03-07. Orange Co. Steve Hall - Several heard singing at the edge of a marshy slough. Mixed in with larger chorus of Southern Leopard Frogs and Pickerel Frogs. Between 2100 and 2200 following a heavy downpour. ~64 F.
	2022-04-13. Madison Co. Jim Petranka and Becky Elkin - Several adults singing among a large chorus of Spring Peepers; moderate rains earlier in the day.

Photo Gallery for Anaxyrus americanus - American Toad		21 photos are shown.
	Recorded by: R. Spainhour Surry Co.	Recorded by: R. Spainhour Surry Co.
	Recorded by: David George Orange Co.	Recorded by: Travis McLain Stokes Co.
	Recorded by: John Petranka Madison Co.	Recorded by: A. Pharr Gaston Co.
	Recorded by: J. Buie Stokes Co.	Recorded by: John Petranka Orange Co.
	Recorded by: H. Quay Orange Co.	Recorded by: Steve Hall and Savannah Hall Orange Co.
	Recorded by: Morgan Freese Buncombe Co.	Recorded by: Jim Petranka Madison Co.
	Recorded by: Owen McConnell Durham Co.	Recorded by: Owen McConnell Durham Co.
	Recorded by: Owen McConnell Graham Co.	Recorded by: Jim Petranka and Becky Elkin Transylvania Co.
	Recorded by: Steve Hall Orange Co.	Recorded by: Steve Hall Orange Co.
	Recorded by: Steve Hall Orange Co.	Recorded by: Steve Hall Orange Co.
	Recorded by: Steve Hall Orange Co.

Anaxyrus americanus - American Toad

Recording Gallery for Anaxyrus americanus - American Toad

Photo Gallery for Anaxyrus americanus - American Toad

21 photos are shown.