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Southern Toad

Anaxyrus terrestris

What do they look like?

Southern toads range in size from approximately 40 to 113 mm long, with an average mass of about 19 g. Size varies somewhat by population; for example, individuals found on Georgia's barrier islands tend to be larger than those found on the mainland. Coloration is usually brown, grey, or reddish, with several dorsal spots and warts. The belly is usually greyish in color, and the chest area is spotted. They have high cranial crests with pronounced knobs, located between and behind the large, protruding eyes. These knobs help distinguish Southern toads from American toads (Anaxyrus americanus) and Fowler's toads (Anaxyrus fowleri). Southern toads have wide mouths, large heads, and short bodies with no tail. Their muscular hind limbs are modified for jumping. These toads are sexually dimorphic: males have darker throats (possibly always, but at least during breeding season) and are smaller than females. Tadpoles are generally solid black with a diagonal gold line located behind the eye. (Duellman, 2004; Elliott, et al., 2009; Forster, 2013; Hammerson, 2013; Jensen, et al., 2008; Tacutu, et al., 2013)

  • Sexual Dimorphism
  • female larger
  • sexes colored or patterned differently
  • Average mass
    19 g
    0.67 oz
  • Average mass
    19.267 g
    0.68 oz
  • Range length
    40 to 113 mm
    1.57 to 4.45 in
  • Range basal metabolic rate
    1.25 to 1.8 cm3.O2/g/hr
  • Average basal metabolic rate
    1.5 cm3.O2/g/hr

Where do they live?

Southern toads are found in the southeastern United States, in the Atlantic and Gulf Coastal Plain regions. Their range extends as far west as Louisiana, and from southern Florida (including the Florida Keys) north through the Carolinas and into southeastern Virginia. Many populations are disjunct; for example, they are found in Georgia only below the Fall Line, but also in portions of the Blue Ridge and Piedmont regions of South Carolina. (Duellman, 2004; Elliott, et al., 2009; Hammerson, 2013; Jensen, et al., 2008; Jensen, 2013)

What kind of habitat do they need?

Southern toads are generally restricted to sandy soil habitats around coastal plains. They are typically found in pinewoods, scrub oak, and mixed forest environments; they may also be found in agricultural fields or even in backyards. These toads bury into soft soil during the day and many also be found hidden under logs or other debris. They require fresh water for laying their eggs and during their initial larval life stages. (Edwards, et al., 2006; Elliott, et al., 2009; Hammerson, 2013; Jensen, et al., 2008; Jensen, 2013; Metts, et al., 2012)

  • Aquatic Biomes
  • lakes and ponds
  • rivers and streams
  • temporary pools

How do they grow?

Eggs, generally 1-1.4 mm in diameter, are deposited in long coils. Females lay their eggs in shallow freshwater, usually in vegetation. Eggs hatch within 2-4 days. Southern toads begin life as legless tadpoles that breathe through internal gills, have pronounced tails used for swimming, and exhibit a vegetarian diet (aquatic plant life and algae). The tadpole larval period lasts from 30 to 55 days; metamorphosis begins when individuals reach a length of 6.5-11 mm. Tadpoles are unpalatable, potentially even toxic, to potential predators, and can be seen swimming in open water, often in schools. As tadpoles metamorphose, they absorb their tails, grow limbs, develop lungs and begin to breathe air, finally moving onto land and switching to the carnivorous diet of adults. (Elliott, et al., 2009; Hammerson, 2013; Jensen, 2013; Metts, et al., 2012; Moseley, et al., 2004)

How do they reproduce?

Males may either call to females and wait or move through a breeding area (shallow freshwater areas such as temporary or permanent pools and ponds) in search of potential mates. During breeding season, males issue a shrill, trilling advertising call, 4-8 seconds in length, to attract females. There may be several males in the same body of water and their combined calls can be quite loud. Competition can result in multiple matings with multiple partners for both sexes. During mating, a male climbs on a female's back, grasping her behind the forelimbs in a position called axillary amplexus, and releasing sperm as she releases eggs; fertilization is external. Males will produce a release vocalization after breeding, comprised of a series of chirps or notes, along with a low-pitched, soft hum and abdominal vibration. (Duellman, 2004; Elliott, et al., 2009; Jensen, et al., 2008)

Breeding season for southern toads is February through October, depending on location, though most breeding takes place during the earlier months of this range. These toads migrate from their sandy, upland habitats to breeding sites near freshwater; adults may return to the same body of water in which they hatched or migrate to a different water source. Breeding aggregations can be quite large. During breeding, females eject clutches of 2500-4000 eggs, which are encased in a jelly-like substance and are released into shallow freshwater. Southern toads reach sexual maturity within 2-3 years (42-82 mm snout-vent length for males, 44-92 mm snout-vent length for females). Southern toads are capable of hybridizing with Fowler's toads (Anaxyrus fowleri) and American toads (Anaxyrus americanus). (Duellman, 2004; Elliott, et al., 2009; Jensen, et al., 2008; Jensen, 2013; Metts, et al., 2012)

  • How often does reproduction occur?
    Southern toads may mate multiple times during the breeding season.
  • Breeding season
    Breeding season for this species is from February through October, with most breeding completed by mid-summer.
  • Range number of offspring
    2500 to 4000
  • Average number of offspring
  • Range time to hatching
    2 to 4 days
  • Range age at sexual or reproductive maturity (female)
    2 to 3 years
  • Range age at sexual or reproductive maturity (male)
    2 to 3 years

Neither male nor female Southern toads exhibit parental investment beyond laying and fertilizing eggs. (Elliott, et al., 2009; Jensen, et al., 2008; Metts, et al., 2012; Moseley, et al., 2004)

  • Parental Investment
  • no parental involvement

How long do they live?

The lifespan of southern toads is not well documented, but there have been individuals held in captivity for as long as 10 years. American toads (Anaxyrus americanus), which are closely related, are said to have a lifespan of up to 10 years in the wild. (Elliott, et al., 2009; Hammerson, 2013; Jensen, 2013; Tacutu, et al., 2013)

  • Range lifespan
    Status: captivity
    10 (high) years
  • Typical lifespan
    Status: wild
    10 (high) hours
  • Average lifespan
    Status: captivity
    10 years

How do they behave?

Southern toads are mainly nocturnal, usually hiding in self-made burrows during the day and feeding at night. They are commonly seen near residential areas and other buildings, which may attract insects with their outdoor lights. Adults are mainly terrestrial until breeding season, when they migrate to nearby wetlands to breed. Males emit an advertising call to attract females during breeding season; they may also call during heavy rains at any time of the year, though this will not be accompanied by breeding. In hybridized individuals, calls will sound like a mix of the calls of both species. Southern toads have skin that is very water permeable, allowing potentially rapid evaporative water loss across the skin. To combat dehydration, southern toads are capable of storing large quantities of water in their bladders and reabsorbing it as needed. They are much less active during colder months, burrowing to depths of a foot or more. (Duellman, 2004; Elliott, et al., 2009; Forster, 2013; Hammerson, 2013; Jensen, et al., 2008; Jensen, 2013; Metts, et al., 2012)

  • Range territory size
    1.6 (high) km^2

Home Range

Adults inhabit home ranges that may extend up to 1.6 km^2. Adults migrate to wetlands during the breeding season. (Elliott, et al., 2009; Jensen, et al., 2008; Jensen, 2013; Metts, et al., 2012)

How do they communicate with each other?

Southern toads rely mainly on their well-developed eyesight for detecting potential prey. During breeding season, they rely on sound production and processing in order to find mates. (Duellman, 2004; Duellman, 2004; Edwards, et al., 2006; Elliott, et al., 2009; Jensen, et al., 2008; Metts, et al., 2012)

What do they eat?

Southern toad tadpoles have a mainly vegetarian diet, consisting of algae and other plant material; they may feed on material suspended in the water or scrape it from the substrate. They have also been observed consuming eggs from dead gravid adult females. Adult southern toads are carnivorous and feed mainly on invertebrates including spiders, beetles, ants, and other insects. Prey is captured using a quick flip of the tongue, which is coated in sticky secretions, and is swallowed whole. These toads may develop fat reserves in order to sustain them through winter months. (Duellman, 2004; Elliott, et al., 2009; Forster, 2013; Jensen, 2013; Moseley, et al., 2004; Schacht, 2009; Todd and Rothermel, 2006)

  • Animal Foods
  • eggs
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • algae

What eats them and how do they avoid being eaten?

Southern toads rely heavily on camouflage to protect them from predators. If caught, they may inflate their lungs in order to appear larger. These toads secrete bufotoxin, a cardiotoxic substance, which makes them unpalatable or even toxic to predators. Southern toads have been observed attempting to escape from predators by charging, moving side-to-side, or kicking sand at them. Eggs and tadpoles may also be unpalatable or toxic to predators. Nonetheless, eggs, tadpoles, and adults are all prey items for many invertebrate and vertebrate predators. (Duellman, 2004; Elliott, et al., 2009; Hammerson, 2013; Jensen, 2013)

  • These animal colors help protect them
  • cryptic

What roles do they have in the ecosystem?

Some trematode larvae parasitize southern toad tadpoles, often using them as intermediate hosts. It has been shown that some trematodes may exhibit a preference for this species as a host. (Jensen, 2013; Sears, et al., 2012)

Commensal or parasitic species (or larger taxonomic groups) that use this species as a host

Do they cause problems?

There are no known adverse affects of this species on humans. (Duellman, 2004; Edwards, et al., 2006; Elliott, et al., 2009; Hammerson, 2013; Moseley, et al., 2004)

How do they interact with us?

There are no known positive economic impacts of this species for humans. In some areas, southern toads may consume insects that would be considered to be pests. (Duellman, 2004; Edwards, et al., 2006; Elliott, et al., 2009; Hammerson, 2013)

  • Ways that people benefit from these animals:
  • controls pest population

Are they endangered?

Southern toads are listed as a species of "least concern" by the International Union for the Conservation of Nature and Natural Resources. They are not currently considered to be threatened or endangered by any agency, although population numbers have decreased in areas where cane toads (Rhinella marina)have been introduced (in southern Florida, particularly). (Hammerson, 2004; Hammerson, 2013)

Some more information...

This species was previously known as Anaxyrus terrestris In 2006, the genus Bufo was split into multiple genera, including Anaxyrus. Nevertheless, some current researchers continue to use the original name for the species in publications, and it has been suggested that the original genus designation should be reinstated, with Anaxyrus considered a subgenus. (Frost, et al., 2006; Smith and Chiszar, 2006)


Jeff Jenkins (author), Sierra College, Jennifer Skillen (editor), Sierra College, Jeremy Wright (editor), University of Michigan-Ann Arbor.


Duellman, W. 2004. Anura (Frogs and Toads). Pp. 61-68 in M Hutchins, ed. Grzimek's Animal Life Encyclopedia, Vol. 6, 2 Edition. Detroit: Gale Virtual Reference Library. Accessed May 09, 2013 at

Edwards, T., K. McCoy, T. Barbeau, M. McCoy, J. Thro, L. Guillette Jr. 2006. Environmental context determines nitrate toxicity in Southern toad (Bufo terrestris) tadpoles. Aquatic Toxicology, 78/1: 50-58. Accessed March 14, 2013 at

Elliott, L., H. Gerhardt, C. Davidson. 2009. The Frogs and Toads of North America: A Comprehensive Guide to Their Identification, Behavior, and Calls. Boston, MA: Houghton Mifflin Harcourt. Accessed April 05, 2013 at

Forster, C. 2013. Dehydration in Southern toads (Anaxyrus terrestris): Metabolic costs and effects of temperature selection. Scripps Senior Theses, Paper 161: 1-19. Accessed August 13, 2013 at

Frost, D., T. Grant, J. Faivovich, R. Bain, A. Haas, C. Haddad, R. De Sa, A. Channing, M. Wilkinson, S. Donnellan, C. Raxworthy, J. Campbell, B. Blotto, P. Moler, R. Drewes, R. Nussbaum, J. Lynch, D. Green, W. Wheeler. 2006. The Amphibian Tree of Life. Bulletin of the American Museum of Natural History, 297: 1-371. Accessed June 09, 2013 at

Hammerson, G. 2013. "Anaxyrus terrestris" (On-line). NatureServe. Accessed May 11, 2013 at

Hammerson, G. 2004. "Anaxyrus terrestris" (On-line). International Union for Conservation of Nature and Natural Resources. Accessed August 15, 2013 at

Jensen, J. 2013. "Anaxyrus terrestris" (On-line). Amphibiaweb. Accessed August 14, 2013 at

Jensen, J., M. Elliott, W. Gibbons, C. Camp. 2008. Amphibians and Reptiles of Georgia. Athens, GA: University of Georgia Press. Accessed April 06, 2013 at,+J.B.,+2008.+Southern+toad+Bufo+(Anaxyrus)+terrestris.+In:+Jensen,+J.B.,&lr=&source=gbs_navlinks_s.

Metts, B., K. Buhlmann, D. Scott, T. Tuberville, W. Hopkins. 2012. Interactive effects of maternal and environmental exposure to coal combustion wastes decrease survival of larval southern toads (Bufo terrestris). Environmental Pollution, 164: 211-218. Accessed March 16, 2013 at

Moseley, K., S. Castleberry, J. Hanula, W. Ford. 2004. Diet of southern toads in Loblolly pine stands subject to coarse woody debris manipulations. The American Midland Naturalist, 153: 327-337. Accessed March 16, 2013 at

Schacht, M. 2009. Factors promoting variation in feeding morphology of larval southern toads (Bufo terrestris). Electronic Theses and Dissertations: Georgia Southern University: 1-96. Accessed August 13, 2013 at

Sears, B., A. Schlunk, J. Rohr. 2012. Do parasitic trematode cercariae demonstrate a preference for susceptible host species?. PLoS ONE, 7/12: e51012. Accessed May 11, 2013 at

Smith, H., D. Chiszar. 2006. Dilemma of name recognition: Why and when to use new combinations of scientific names. Herpetological Conservation and Biology, 1/1: 6-8. Accessed June 09, 2013 at

Tacutu, R., T. Craig, A. Budovsky, D. Wuttke, G. Lehmann, D. Taranukha, J. Costa, V. Fraifeld, J. de Magalhaes. 2013. "AnAge entry for Anaxyrus terrestris" (On-line). AnAge: The Animal Ageing and Longevity Database. Accessed May 11, 2013 at

Todd, B., B. Rothermel. 2006. Assessing quality of clearcut habitats for amphibians: Effects on abundances versus vital rates in the Southern toad (Bufo terrestris). Biological Conservation, 133/2: 178-185. Accessed March 16, 2013 at

University of Michigan Museum of ZoologyNational Science Foundation

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Jenkins, J. 2015. "Anaxyrus terrestris" (On-line), Animal Diversity Web. Accessed October 21, 2017 at

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
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