Farancia abacuraabacura

Geographic Range

Mud snakes, Farancia abacura, are commonly found in the southeastern portion of the United States. The location of mud snakes ranges throughout the southern portion of Virginia's Coastal Plain, southward toward Mississippi, Louisiana and western Tennessee. Mud snakes have been also found as far east as the western half of Tennessee and southward to the Gulf coast.

Two subspecies of Farancia abacura include eastern mud snakes (Farancia abacura abacura) and western mud snakes (Farancia abacura reinwardtii). Eastern mud snakes can be found as far north as Virginia's southern Coastal Plain, and as far south as the southern tip of Florida. Western mud snake can be found as north as the western portion of Tennessee, as far south as Louisiana and they can also be found along the eastern portion of Mississippi. The overlap of western and eastern mud snakes can be found toward southern Mississippi and toward the northern region of Georgia. (Gibbons and Dorcas, 2015; Meade, 1946; Mitchell, 1994)

Habitat

Mud snakes commonly inhabit swampy lowlands where they use the wet conditions to burrow themselves in mud. They are more commonly found in wooded swamplands with lots of rotten logs surrounding the area and they can also be found in lakes and ponds that have muddy or sandy bottoms. In addition, they can also be found in salty marshes, the edges of rivers and tidal streams. These aquatic habitat can be freshwater or brackish waters. (Ernst and Ernst, 2003; Meade, 1946; Snyder, 1945)

Physical Description

Mud snakes are non-venomous snakes with vibrant coloration and patterns. Adult mud snake total length ranges between 91.4 and 121.9 cm. Female mud snakes usually have thicker bodies than males, while males have longer tails. Some individuals are bluish-gray to black, often with a metallic sheen. Their sides are dark with a sporadic series of salmon, pink, or reddish bars and alternating reddish and black bars across the venter. Their necks are slightly constricted and they have a flat head. Mud snake tongues are small and their eyes are small, flat and inconspicuous due to their burrowing habits. The top of their head is mostly black, whereas the center of each light-colored upper and lower lip contains distinct central dark spots. The same dark spots appear on the yellow or orange chin. The dorsal scales of mud snakes are smooth and arranged in 19 rows at mid-body (range 18 to 21). On the venter are 167 to 208 ventral scales, 31 to 55 subcaudal scales and normally a divided anal plate. They average 13.2 teeth (range 11 to 16).

Juvenile mud snakes are slender and smaller than adults (about 17.8 to 22.9 cm long). Overall, the juvenile mud snakes have a similar appearance to the adults: black above, checkered black and red venter. Juveniles possess a needle-like tail that adults lack. (Ernst and Ernst, 2003; Meade, 1946; Zug, et al., 2001)

  • Sexual Dimorphism
  • female larger
  • sexes shaped differently
  • Range length
    91.4 to 121.9 cm
    35.98 to 47.99 in

Development

Mud snakes are egg layers and they can lay between 6 to 104 eggs. Gestation could last about 56 days and the time from egg-laying to hatching could last about 60 days (range 37-80). When the young hatch could be 22.0 cm long (range 15.2-27.0 cm) and could weigh around 6.3 g (range: 2.5-8.0). In about a six-month span post-hatching, they can grow about 13.9 cm. When juvenile mud snakes hatch, they look like the adult mud snakes in color and pattern. During the first week post-hatching, the juveniles go through similar color changes that the adults go through before molting. On the seventh day post-hatching, they shed their skin. It takes about 2.5 years to reach their full adult length, but if food availability allows, they can continue to grow into adulthood. This suggest that mud snakes exhibit indeterminate growth, like most snake do. (Ernst and Ernst, 2003; Gray, 2005; Meade, 1946; Werler and Dixion, 2010; Zug, et al., 2001)

Reproduction

During mating season, male mud snakes use skin pheromones to attract females. Once the males determine the sex of the individual they encounter, they will begin to court the individual if it is a female. Males mate with females in three phases: tactile-chase, tactile-alignment, and intromission-coitus. In tactile-chase, males try to place their bodies alongside the females’ dorsal surface in a wavelike manner. During tactile-alignment, males attempt to mate with the females. This involves rapid muscle contractions of the males’ tails as they try to align with the females’ tails. During the final phase, the females gape their cloacas to allow the insertion of a single hemipenis, resulting in intromission and coitus. Male mud snakes are polygynous, which means they are capable of mating with more than one female mud snake.

When male mud snakes want to show their dominance, they do it through combat. That is generally a contest in which one male tries to push down the head of the other male. (Gray, 2005; Meade, 1946; Solberg and Reynolds, 1942; Werler and Dixion, 2010; Zug, et al., 2001)

Mud snakes of both sexes reach sexual maturity in about 2.5 years. Female mud snakes produce one clutch per year. The breeding season is March-April in Florida, and July-September through the remainder of their range. Gestation could last about 56 days, and the time from egg-laying to hatching could last about 60 days (range 37-80). Females lay between 6 -104 eggs at a time, with an average clutch of 27 eggs. The eggs are creamy white, smooth and tough. The eggs range between 2.4 to 4.8 cm in diameter and weigh 7.9-11.0 g. This species’ reproductive behavior is different from other snakes, other than pythons, because they exhibit maternal care during incubation. The females do not spend time with the young once the eggs are hatched, and therefore the young are fully independent at hatching. (Gray, 2005; Meade, 1946; Solberg and Reynolds, 1942; Werler and Dixion, 2010)

  • Breeding interval
    Mud snakes breed once a year
  • Breeding season
    March through April in Florida, July through September elsewhere
  • Range number of offspring
    6 to 104
  • Average number of offspring
    27
  • Average gestation period
    56 days
  • Average time to independence
    0 days
  • Average age at sexual or reproductive maturity (female)
    2.5 years
  • Average age at sexual or reproductive maturity (male)
    2.5 years

Female mud snakes provide parental care before eggs hatch, and males do not play a role in raising the young. Females tightly coil up with their eggs and they remain coiled until the eggs are hatched. The only time the females leave their young is when they have to feed or shed their skin. There is no evidence that female mud snakes can raise their body temperature according to their surroundings to increase the temperature of the eggs during incubation. Further, there is no evidence that the females watch over the young post-hatching.

Female mud snakes were suspected to nest-guard to protect the eggs from predators. However, when researchers observed the snakes in the wild or in captivity, females did not attempt to protect the nest from any predators. Nothing was reported of any behavior such as biting or striking. One anecdotal observation of a tightly coiled female mud snake in the wild supported this. When researchers approached the female to examine the eggs, the female hid her head from view and then escaped through the bottom of the nest materials. (Gray, 2005; Meade, 1946; Werler and Dixion, 2010; Zug, et al., 2001)

  • Parental Investment
  • female parental care
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female

Lifespan/Longevity

The longest recorded lifespan of mud snakes in captivity was about 19 years. No information on lifespan in the wild is currently available. (Northeast Partners in Amphibian and Reptile Conservation, 2017)

  • Average lifespan
    Status: captivity
    19 years

Behavior

Mud snakes in the northern portion of their geographic range must hibernate, but they are active year-round further south. Mud snakes have the ability to live in water and also on land. Some mud snakes leave the water in late fall and burrow deeply into wood of decaying pine trees or banks overlooking the water. It is not reported when the snakes actually return to the water. It is uncommon to find mud snakes far from the water. When on land, they spend most of their time buried in mud.

In captivity, mud snakes stop feeding in October. They will hibernate in a hole underground in November. Occasionally they will emerge and drink some water. The emerge from hibernation in March. These snakes are often conditioned well, as it has been noted that they are not sluggish and have frequent tongue motions.

Mud snakes are active at night especially during the summer. During rainstorms, they hide under aquatic plants or in burrows. In the spring, they are active during the daytime, at least in Florida. (Gray, 2005; Meade, 1946; Werler and Dixion, 2010; Zug, et al., 2001)

Home Range

Although home ranges have not been reported for mud snakes, a study of movement in western mud snakes reported that individuals were typically 62 m (range 0-264m) away from the land-water interface of a wetland. Individuals were as far as 1288m away from wetlands. They are not known to defend a territory. (Steen, D., et al., 2013)

Communication and Perception

Initial social communications in mud snakes are chemical, but tactile interactions are used as close range signals between the sexes and also between the males. When male mud snakes want to show their dominance, they do it through combat. That is generally a contest in which one male tries to push down the head of the other male.

Some skin pheromones are used by females during the breeding season. These pheromones allow individuals to identify members of their own species. Paired cloacal glands are produce these and other pheromones used for defense and trailing other females. Defense pheromones are foul-smelling, deterring humans and other potential predators from handling them.

Females tightly coil up with their eggs and they remain coiled until the eggs are hatched. This is a tactile effort to assist in protecting young prior to hatching.

When young mud snakes are bitten by a predator, they stab the predator with their spine-like tails to make the predator release its hold. Larger individual mud snakes have sufficient body strength to break the hold without the use of the spine. (Meade, 1946; Zug, et al., 2001)

Food Habits

Mud snakes are carnivores and their prey consists of aquatic salamanders, amphiumas, and sirens. Typical species within their range include: mole salamanders (Ambystoma talpoideum), two-toed amphiumas (Amphiuma means), one-toed amphiumas (Amphiuma pholeter), greater sirens (Siren lacertina), and northern dwarf sirens (Pseudobranchus striatus).Their diet also consists of frogs, tadpoles, and occasionally fish. Mud snakes have enlarged teeth at the rear of their jaws that probably give them a more firm grip on large slippery amphiumas and sirens. Juvenile mud snakes eat small salamanders, small frogs, and tadpoles. (Dabney, 1919; Ernst and Ernst, 2003; Meade, 1946; Werler and Dixion, 2010)

  • Primary Diet
  • carnivore
    • eats terrestrial vertebrates
  • Animal Foods
  • amphibians
  • fish

Predation

Mud snakes are eaten by a variety of predators that include other snakes, carnivorous mammals, such as raccoons and skunks, and large wading birds, such as herons. American alligators (Alligator mississippiensis) and cottonmouths (Agkistrodon piscivorous) also prey on mud snakes. Large wading birds, such as herons, prey on juvenile mud snakes. When mud snakes are disturbed, they often tuck their heads and curl their tail to displays their red and black venter. Sometimes they roll over on their backs to display their red and black belly. Those flashes of color act as a warning signal that mimics the venomous coral snakes (Micrurus fulvius). (Ernst and Ernst, 2003; Gibbons and Dorcas, 2015)

Ecosystem Roles

There are several parasites that infects the mud snakes. A cestode, Proteocephalus faranciae, infects the intestines. Tongue worms, Kiricephalus coarctatus, infect lungs, muscles, and kidneys. Finally, trematodes, Pneumatophilus tracheophilus, infect trachea and lungs. Mud snakes can be infected by fungal diseases including, Ophidiomyces ophiodiicola, which leads to severe dermatitis and facial disfiguration in captive mud snakes. (Goodman and Monks, 2006; Last, et al., 2016; McAllister, 2015; Goodman and Monks, 2006; Last, et al., 2016; McAllister, 2015)

Commensal/Parasitic Species
  • cestodes (Proteocephalus faranciae)
  • tongue worms (Kiricephalus coarctatus)
  • trematodes (Pneumatophilus tracheophilus)
  • fungal disease (Ophidiomyces ophiodiicola)

Economic Importance for Humans: Positive

Mud snakes are sometimes kept as pets. A Florida study from 1990-1994 reported that 246 mud snakes were captured and sold as part of the Florida pet trade. (Enge, 2005)

Economic Importance for Humans: Negative

Mud snakes do not have a negative impact on the economy.

Conservation Status

Mud snakes are listed as a species of "Least Concern" by the IUCN Red List, and have no special status on any of the government lists in the United States or on CITES.

Their are no major threats to the mud snakes; some minor ones include loss of habitat or fragmentation. Fragmentation makes it hard for these snakes to travel without having to go across a highway. In the Payne Prairie State Preserve in Florida, they had a problem with many vertebrates getting ran over on the highway, and to solve this problem they built barrier wall-culvert system to protect them from getting killed on the highway. (Dodd, et al., 2004)

Contributors

Corney Ricks (author), Radford University, Alex Atwood (editor), Radford University, Karen Powers (editor), Radford University, Joshua Turner (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

aposematic

having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

bog

a wetland area rich in accumulated plant material and with acidic soils surrounding a body of open water. Bogs have a flora dominated by sedges, heaths, and sphagnum.

brackish water

areas with salty water, usually in coastal marshes and estuaries.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

estuarine

an area where a freshwater river meets the ocean and tidal influences result in fluctuations in salinity.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

freshwater

mainly lives in water that is not salty.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

marsh

marshes are wetland areas often dominated by grasses and reeds.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

visual

uses sight to communicate

References

Blackwell, E., J. Johnson. 2011. Population dynamics of two aquatic salamanders, Siren intermedia and Amphiuma tridactylum in the Mississippi Delta. BIOS, 82/3: 72-77.

Buck, D. 1946. Food of Farancia abacura in Texas. Herpetologica, 3/4: 111.

Dabney, T. 1919. Character and feeding habits of Farancia abacura, the socalled ‘stinging snake'. Copiea, 1919/73: 73-75.

Dodd, K., W. Barichivich, L. Smith. 2004. Effectiveness of a barrier wall and culverts in reducing wildlife mortality on a heavily traveled highway in Florida. Biological Conservation, 118/5: 619-631.

Dwight, D. 1948. Flash display of aposematic colors in Farancia and other snakes. Copeia, 1948/3: 208-211.

Enge, K. 2005. Commercial harvest of amphibians and reptiles in Florida for the pet trade. Pp. 198-211 in E Kevin, ed. Amphibians and Reptiles: Status and Conservation in Florida. Malabar, Florida: Krieger Publishing Company.

Ernst, C., E. Ernst. 2003. Snakes of the United States and Canada. Washington, D.C.: Smithsonian Institution Press.

Etheridge, R. 1950. Color variants in snakes from the southeastern United States. Copeia, 1950/4: 321.

Ford, N., D. Lancaster. 2007. The species-abundance distribution of snakes in a bottomland hardwood forest of the southern United States. Journal of Herpetology, 41/3: 385-393.

Gibbons, W., M. Dorcas. 2015. Snakes of the Southeast. Athens, Georgia: University of Georgia Press.

Goodman, J., S. Monks. 2006. Taxonomic Revision of Pneumatophilus Odhner, 1910, and description of Pneumatophilus tracheophilus n. sp.(Ochetosomatoidea: Ochetosomatidae) from the mud snake, Farancia abacura abacura (Serpentes: Colubridae: Xenodontinae. Comparative Parasitology, 73/1: 14-19.

Gray, B. 2005. The Serpent's Cast: A Guide to the Identification of Shed Skins from Snakes of the Northeast and Mid-Atlantic States. Lansing, Michigan: ECO Herpetological Publishing & Distribution.

Hall, P., A. Meier. 1993. Reproduction and behavior of western mud snakes (Farancia abacura reinwardtii) in American alligator nests. Copeia, 1993/1: 219-222.

Last, L., H. Fenton, J. Gonyor-McGuire, M. Moore, M. Yabsley. 2016. Snake fungal disease caused by Ophidiomyces ophiodiicola in a free-ranging mud snake (Farancia abacura). Journal of Veterinary Diagnostic Investigation, 28/6: 709-713.

Linzey, D., M. Clifford. 1981. Snakes of Virginia. Charlottesville, Virginia: University of Virginia Press.

Lowichik, A., R. Yaeger. 1987. Ecological aspects of snake Hemogregarine infections from two habitats in southeastern Louisiana. The Journal of Parasitology, 73/6: 1109-1115.

McAllister, C. 2015. New host and distributional records for helminth parasites (Trematoda, Cestoidea, Nematoda) of herpetofauna from southeastern Oklahoma. Proceedings of the Oklahoma Academy of Science, 92: 29-36.

McDaniel, R., K. John. 1983. Farancia abacura. Catalogue of American Amphibians and Reptiles: 314.1-314.2.

Meade, G. 1946. The natural history of the mud snake. The Scientific Monthly, 63/1: 21-29.

Meade, G. 1940. observations on Louisiana captive snakes. Copeia, 1940/3: 165-168.

Mitchell, J. 1994. The Reptiles of Virginia. Washington, DC: Smithsonian Institution Press.

Neil, W. 1964. Taxonomy, natural history, and zoogeography of the rainbow snake, Farancia erytrogramma (Palisot de Beauvois). The American Midland Naturalist, 71/2: 257-298.

Northeast Partners in Amphibian and Reptile Conservation, 2017. "Northeast Partners in Amphibian and Reptile Conservation" (On-line). Accessed October 25, 2017 at http://northeastparc.org/.

Powell, C., D. Stevenson, M. Smith, J. Jensen. 2010. A new clutch size record for the mud snake (Farancia abacura). Southeastern Naturalist, 9/1: 177-178.

Riemer, W. 1957. The snake Farancia abacura: An attended nest. Herpetologica, 13/1: 31-32.

Snyder, R. 1945. Notes on the snakes of southeastern Alabama. Copeia, 1945/3: 173-174.

Solberg, A., F. Reynolds. 1942. Notes on the life history of the mud snake. Copeia, 1942/1: 25-26.

Steen, D., D., D. Stevenson, J. Beane, J. Willson, M. Aresco, J. Godwin, S. Graham, L. Smith, J. Howze, D. Rudolph, J. Pierce, L. Lee, B. Gregory, J. Jensen, S. Stiles, J. Stiles, N. Nazdrowicz, C. Guyer. 2013. Terrestrial movements of the red-bellied mudsnake (Farancia abacura) and rainbow snake (F. erytrogramma). Herpetological Review, 44/2: 208-213.

Van Hyning, O. 1932. Food of some Florida snakes. Copeia, 1932/1: 37-37.

Werler, J., J. Dixion. 2010. Texas Snakes: Identification, Distribution, and Natural History. Austin, TX: University of Texas Press.

Wilson, l. 1995. The Land Manager's Guide to the Amphibians and Reptiles of the South. Chapel Hill, North Carolina: The Nature Conservancy, Southeastern Region.

Zug, G., L. Witt, J. Caldwell. 2001. Herpetology: An Introductory Biology of Amphibians and Reptiles. San Diego, CA: Academic Press.