Animal Diversity Web

Ge­o­graphic Range

Corn snakes are found through­out the east­ern and south­ern cen­tral United States, into north­ern Mex­ico. Two sub­species, Pan­therophis gut­ta­tus gut­ta­tus (corn snake) and P. gut­ta­tus emoryi (Great Plains rat snake) are cur­rently rec­og­nized. Corn snakes are found from south­ern New Jer­sey to Florida and west­ward through Mis­sis­sippi to Louisiana. The range of Great Plains rat snakes ex­tends from south­west­ern Illi­nois through Texas and into north­ern Mex­ico, and as far west as east­ern New Mex­ico. (Bartlett and Bartlett, 2005; Bur­brink, 2002; Co­nant and Collins, 1998)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Corn snakes can be found in a wide va­ri­ety of ter­res­trial habi­tats, pre­fer­ring de­cid­u­ous forests and rocky re­gions where crevices and logs pro­vide nests. They can also be found in fields, grassy areas, and in sub­ur­ban areas near homes and barns. This species has been found in moun­tain­ous re­gions up to about 1800 m in el­e­va­tion but typ­i­cally pre­fer lower el­e­va­tions. (Bartlett and Bartlett, 2005)

• Habitat Regions
• temperate
• terrestrial

• Terrestrial Biomes
• savanna or grassland
• forest

• Other Habitat Features
• suburban

• Range elevation

  1800 (high) m

  5905.51 (high) ft

Phys­i­cal De­scrip­tion

Corn snakes are mild-tem­pered, non-ven­omous snakes. Large spots run along dor­sal side of the body, while the flat un­der­side com­monly has a black and white check­ered pat­tern. The body tends to be brown and red-or­ange, but col­ors vary with re­gion and can in­clude gray and yel­low. In cap­tiv­ity, breed­ers have cre­ated a wide va­ri­ety of color pat­terns, or morphs. Pet corn snakes range in color from white to yel­low to black, though most still re­tain the pri­mary red/brown col­ors. Cap­tive pat­terns in­clude spots, stripes, and solid col­or­ing over the snake's body. Males are larger than fe­males, with an av­er­age length of 70 to 120 cm for the com­bined sexes. Snakes in warmer cli­mates tend to be shorter, with an av­er­age adult length of ap­prox­i­mately 48 cm. Hatch­lings are paler and duller when they first hatch, and mea­sure 20 to 35 cm. (Bartlett and Bartlett, 2005; Mat­ti­son, 2007)

Corn snakes can some­times be con­fused with ven­omous south­ern cop­per­heads (Agk­istrodon con­tor­trix), but the two can be dif­fer­en­ti­ated by the nar­rower head, lighter col­oration, and square-shaped spots that are found in red corn snakes. (Bartlett and Bartlett, 2005; Mat­ti­son, 2007)

• Other Physical Features
• heterothermic

• Sexual Dimorphism
• male larger

• Average mass

  900 g

  31.72 oz

  AnAge

• Range length

  48 to 120 cm

  18.90 to 47.24 in

De­vel­op­ment

Ju­ve­nile corn snakes are fully de­vel­oped when hatched. This species has ZZ/ZW sex de­ter­mi­na­tion, with the male snake con­tribut­ing only Z chro­mo­somes, while the fe­male con­tributes the Z or W chro­mo­some that de­ter­mines the gen­der of the hatch­lings (ZZ=male, ZW=fe­male). (Ernst and Bar­bour, 1989)

As they grow, ju­ve­nile corn snakes shed their skin sev­eral times, and will con­tinue to shed after reach­ing adult­hood. After shed­ding, the col­oration of the scales turns more vivid and the pat­terns be­come clearer. Growth is di­rectly re­lated to how much food is avail­able to the snake; ju­ve­niles grow faster on a reg­u­lar diet of warm-blooded an­i­mals. In gen­eral, a ju­ve­nile reaches its full length shortly after reach­ing sex­ual ma­tu­rity, at around two years of age. (Ernst and Bar­bour, 1989; Mat­ti­son, 2007)

• Development - Life Cycle
• indeterminate growth

Re­pro­duc­tion

Not much is known about the mat­ing sys­tems of corn snakes. Dur­ing mat­ing sea­son, the snakes lo­cate each other using pheromones. Males fight each other for dom­i­nance, with the dom­i­nant male earn­ing mat­ing rites to the fe­male. (Ernst and Bar­bour, 1989)

• Mating System
• polygynous

Corn snakes reach sex­ual ma­tu­rity at 16 to 18 months of age. De­pend­ing on the cli­mate, the breed­ing sea­son lasts from March to May, or year-round in the south. Ges­ta­tion lasts one to two months, with fe­males lay­ing 10 to 15 (up to 30) eggs from May to early July in stumps, logs, or bur­rows that are warm and humid. The eggs are white and cylin­dri­cal, mea­sur­ing 3.8 to 6.4 cm in length and 1.3 to 2.5 cm in di­am­e­ter. Find­ing a corn snake nest is very rare, be­cause fe­males seek out se­cluded nest­ing sites. After ap­prox­i­mately two months of in­cu­ba­tion at an ideal tem­per­a­ture of 27.8 de­grees Cel­sius, the eggs hatch be­tween July and Sep­tem­ber. Not all healthy eggs hatch, as some hatch­lings can­not pen­e­trate the tough eggshell. (Ernst and Bar­bour, 1989; Mat­ti­son, 2007; Seigel and Ford, 1991; Stew­art, et al., 2004)

Fe­males in the wild lay one clutch of eggs per year. In cap­tiv­ity, fe­male corn snakes may lay a sec­ond clutch of eggs. If a fe­male snake breeds a sec­ond time, she can pro­duce fer­tile eggs within days of lay­ing her first clutch. She will lay her sec­ond clutch fol­low­ing the same time­line as the first. (Ernst and Bar­bour, 1989; Seigel and Ford, 1991)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• year-round breeding
• sexual
• fertilization
• oviparous

• Breeding interval

  Wild corn snakes breed once annually.

• Breeding season

  Snakes mate in spring; eggs hatch during the summer.

• Range number of offspring

  10 to 30

• Average number of offspring

  10-15

• Average number of offspring

  12

  AnAge

• Range gestation period

  35 to 68 days

• Range age at sexual or reproductive maturity (female)

  16 to 18 months

• Range age at sexual or reproductive maturity (male)

  16 to 18 months

Corn snakes pro­vide no care to their young. Male snakes leave the fe­male after mat­ing, and fe­males leave their eggs after lay­ing them in a se­cluded nest. (Mat­ti­son, 2007)

• Parental Investment
• no parental involvement
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female

Lifes­pan/Longevity

The longest recorded lifes­pan of this species in cap­tiv­ity was just over 32 years. Al­though no in­for­ma­tion on lifes­pan in the wild is cur­rently avail­able, it can be rea­son­ably as­sumed that pre­da­tion and dis­ease cause wild in­di­vid­u­als to have shorter av­er­age lifes­pans. (de Ma­g­a­l­haes and Costa, 2009)

• Range lifespan
  Status: captivity

  32.3 (high) years

• Average lifespan
  Status: captivity

  32.3 years

  AnAge

Be­hav­ior

Corn snakes climb trees or bushes to hunt for prey. In areas in which the pri­mary diet is ro­dents, they also spend time un­der­ground in the bur­rows of their prey. When they are not hunt­ing, they spend much of their time bask­ing on rocks. (Bartlett and Bartlett, 2005; Ernst and Bar­bour, 1989; Mat­ti­son, 2007; Siev­ert, et al., 2005)

When shed­ding their skins, corn snakes be­come ag­gres­sive and reclu­sive. They first rub their nose against rocks and sticks to loosen the skin from the head. Once this is ac­com­plished, they will slither for­ward and the rest of the skin slides off in one long piece. Shed­ding also seems to de­crease a snake's ap­petite, but once the old skin is shed the snake hunts and eats nor­mally. (Bartlett and Bartlett, 2005; Mat­ti­son, 2007)

Corn snake ac­tiv­ity varies among re­gions, gen­er­ally be­com­ing more ac­tive far­ther south in the species’ range. Red corn snakes are gen­er­ally di­ur­nal, but dur­ing warmer pe­ri­ods or in warmer cli­mates sci­en­tists have ob­served them to be cre­pus­cu­lar. They hi­ber­nate in crevices like logs or caves dur­ing the win­ter. In most of their range, corn snakes begin hi­ber­na­tion around Oc­to­ber, emerg­ing in the spring around April. Corn snakes in south­ern re­gions have been ob­served to hi­ber­nate for very brief pe­ri­ods, if at all. (Bartlett and Bartlett, 2005; Ernst and Bar­bour, 1989; Mat­ti­son, 2007; Siev­ert, et al., 2005)

When male corn snakes en­counter each other, they may per­form dis­plays of dom­i­nance, es­pe­cially dur­ing mat­ing sea­son. A male snake shows dom­i­na­tion by a se­ries of spas­tic move­ments and re­strict­ing the move­ment of the weaker male. (Ernst and Bar­bour, 1989)

• Key Behaviors
• terricolous
• diurnal
• crepuscular
• sedentary
• hibernation
• solitary

• Range territory size

  39800 to 269500 m^2

Home Range

Great Plains rat snakes have home ranges that in­crease and de­crease in size with the sea­sons, reach­ing peaks in the late spring and early au­tumn. Ter­ri­tory size ranged from 3.980 ha in the win­ter to 2.695 ha dur­ing peak sea­sons and did not over­lap with the ter­ri­to­ries of other rat snakes. Be­cause of the lim­ited num­ber of stud­ies on corn snake ter­ri­tory size, the find­ings for this sub­species can only be ten­ta­tively ap­plied to the species as a whole. (Sperry and Tay­lor, 2008)

Com­mu­ni­ca­tion and Per­cep­tion

Corn snakes have rather poor eye­sight and de­pend mainly on ol­fac­tion to per­ceive their en­vi­ron­ment. Like other snakes, their tongues, in con­junc­tion with the Ja­cob­son's organ in the roof of the mouth, de­tect scent mol­e­cules in the sur­round­ing en­vi­ron­ment. In ad­di­tion to the pres­ence of these scents, corn snakes can also de­ter­mine the di­rec­tion from which the mol­e­cules were re­leased. Corn snakes can also feel ground vi­bra­tions through­out their body, which are used to lo­cate small or oth­er­wise hid­den prey or preda­tors. Al­though they have no ex­ter­nal ears, snakes have well-de­vel­oped, func­tion­ing inner ears. When sound waves con­tact a snake's skin, the vi­bra­tion is con­ducted through the bones of the jaw to the cochlea. Each of the jaws func­tions in­de­pen­dent of the other in this re­spect, ef­fec­tively al­low­ing stereo hear­ing and di­rec­tional sound lo­ca­tion. (Friedel, et al., 2008; Mat­ti­son, 2007; Zug, et al., 2001)

Corn snakes com­mu­ni­cate in the same ways as most other species of snake. Dur­ing the mat­ing sea­son, males give off pheromones that are de­tected by fe­males. Com­mu­ni­ca­tion is rare out­side of mat­ing sea­son, as they are soli­tary an­i­mals. (Mat­ti­son, 2007)

• Communication Channels
• tactile
• chemical

• Other Communication Modes
• pheromones

• Perception Channels
• visual
• tactile
• acoustic
• vibrations
• chemical

Food Habits

Corn snakes are car­niv­o­rous and do not need to eat often. They eat every few days in the wild. They kill prey by con­stric­tion and con­sume any­thing smaller than they are, in­clud­ing other corn snakes. Over half of their diet con­sists of ro­dents such as hispid cot­ton rats, white-footed mice and other mam­mal prey, such as east­ern moles. In Florida, their diet con­sists mainly of rep­tiles and am­phib­ians, which this may be a cause for this re­gion's smaller snake sizes. Corn snakes will also climb trees and swal­low bird eggs from un­guarded nests. (Bartlett and Bartlett, 2005; Ernst and Bar­bour, 1989; Siev­ert, et al., 2005; Stake, et al., 2005)

• Primary Diet
• carnivore
  • eats terrestrial vertebrates

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• eggs

Pre­da­tion

Corn snakes have few nat­ural preda­tors, mostly larger snakes and birds of prey. Car­niv­o­rous mam­mals may also eat corn snakes. Larger snakes, such as east­ern kingsnakes and black rac­ers, will con­sume corn snakes. A corn snake’s pri­mary method of avoid­ing preda­tors is by cam­ou­flage and flee­ing from dan­ger. Ju­ve­niles hide from preda­tors under tree bark. (Bartlett and Bartlett, 2005; Mat­ti­son, 2007)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • eastern kingsnakes (Lampropeltis getula)
  • black racers (Coluber constrictor)

Ecosys­tem Roles

The biggest im­pact that corn snakes have on their ecosys­tem is their abil­ity to con­trol pop­u­la­tions of small mam­mals and birds. Sev­eral species of api­com­plexan par­a­sites in­fect corn snake blood cells, liver, and lung tis­sue. He­pa­to­zoon gut­tata (named for its host) is thought to be ex­clu­sive to red corn snakes and has been iden­ti­fied in in­di­vid­u­als from south­east Florida. It is not known how the par­a­sites spread from in­di­vid­ual to in­di­vid­ual. (Kim­bell III, et al., 1999; Mat­ti­son, 2007; Plutzer and Kara­nis, 2007; Telford, et al., 2002)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Like many snake species, corn snakes play a vital role in con­trol­ling ro­dent pop­u­la­tions, help­ing to pre­vent the spread of dis­ease and crop dam­age in areas in­hab­ited by hu­mans. Corn snakes are also pop­u­lar pets for rep­tile en­thu­si­asts. Breed­ers have de­vel­oped a va­ri­ety of color morphs for the pet mar­ket. They are easy to care for if proper at­ten­tion is paid to set­ting up their ter­rar­ium (dry, clean, with an area set up for them to bask under a heat lamp) and are gen­er­ally safe for fam­i­lies with chil­dren. As pets, corn snakes are fed high pro­tein diets con­sist­ing mainly of mice and rats, al­though day-old chicks have been shown to pro­vide sim­i­lar nu­tri­tion. (Ar­buckle, 2010; Bartlett and Bartlett, 2005; Mat­ti­son, 2007)

• Positive Impacts
• pet trade
• controls pest population

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Al­though a corn snake's pre­ferred de­fense is to flee, cor­nered snakes will bite hu­mans. (Bartlett and Bartlett, 2005)

• Negative Impacts
• injures humans
  • bites or stings

Con­ser­va­tion Sta­tus

Al­though some nat­ural habi­tat has been lost to human de­vel­op­ment, corn snakes show no sign of being a threat­ened species. (Ham­mer­son, 2012)

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

This species was for­merly known as Elaphe gut­tata. Re­cent phy­lo­ge­netic stud­ies have sug­gested that the name Pan­therophis gut­ta­tus should be ap­plied to this species, New World rat snakes ap­pear to be more closely re­lated to species of the tribe Lam­pro­pel­tini (which in­cludes kingsnakes) rather than Old World rat snakes (for which the generic name Elaphe still ap­plies). (Pyron and Bur­brink, 2009; Utiger, et al., 2002)

Con­trib­u­tors

Sarah Hogrefe (au­thor), Rad­ford Uni­ver­sity, Karen Pow­ers (ed­i­tor), Rad­ford Uni­ver­sity, Kier­sten Newtoff (ed­i­tor), Rad­ford Uni­ver­sity, Melissa Whistle­man (ed­i­tor), Rad­ford Uni­ver­sity, Je­remy Wright (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Ar­buckle, K. 2010. Suit­abil­ity of day-old chicks as food for cap­tive snakes. Jour­nal of An­i­mal Phys­i­ol­ogy and An­i­mal Nu­tri­tion, 94/6: 296-307.

Bartlett, R., P. Bartlett. 2005. Guide and Ref­er­ence to the Snakes of East­ern and Cen­tral North Amer­ica (North of Mex­ico). Gainesville, Florida: Uni­ver­sity Press of Florida.

Bur­brink, F. 2002. Phy­lo­geo­graphic analy­sis of the corn­snake (Elaphe gut­tata) com­plex as in­ferred from max­i­mum like­li­hood and Bayesian analy­ses. Mol­e­c­u­lar Phy­lo­ge­net­ics and Evo­lu­tion, 25/3: 465-476.

Co­nant, R., J. Collins. 1998. A Field Guide to Rep­tiles and Am­phib­ians of East­ern and Cen­tral North Amer­ica. Third Edi­tion, Ex­panded. New York, NY: Houghton Mif­flin Com­pany.

Ernst, C., R. Bar­bour. 1989. Snakes of East­ern North Amer­ica. Fair­fax, Vir­ginia: George Mason Uni­ver­sity Press.

Friedel, P., B. Young, J. van Hem­men. 2008. Au­di­tory Lo­cal­iza­tion of Ground-Borne Vi­bra­tions in Snakes. Phys­i­cal Re­view Let­ters, 100/4: 4 pages.

Ham­mer­son, G. 2012. "Pan­therophis gut­ta­tus" (On-line). The IUCN Red List of En­dan­gered Species. Ac­cessed Feb­ru­ary 07, 2012 at http://​www.​iucnredlist.​org/​apps/​redlist/​details/​63863/​0.

Kim­bell III, L., D. Miller, W. Chavez, N. Alt­man. 1999. Mol­e­c­u­lar analy­sis of the 18S rRNA gene of Cryp­tosporid­ium ser­pen­tis in a wild-caught corn snake (Elaphe gut­tata gut­tata) and a five-species re­stric­tion frag­ment length poly­mor­phism-based assay that can ad­di­tion­ally dis­cern C. parvum from C. wrairi. Ap­plied and En­vi­ron­men­tal Mi­cro­bi­ol­ogy, 65/12: 5345-5349.

Mat­ti­son, C. 2007. The New En­cy­clo­pe­dia of Snakes. Prince­ton, New Jer­sey: Prince­ton Uni­ver­sity Press.

Plutzer, J., P. Kara­nis. 2007. Mol­e­c­u­lar iden­ti­fi­ca­tion of a Cryp­tosporid­ium saurophilum from corn snake (Elaphe gut­tata gut­tata). Parisatol­ogy Re­search, 101/4: 1141-1145.

Pyron, R., F. Bur­brink. 2009. Neo­gene di­ver­si­fi­ca­tion and tax­o­nomic sta­bil­ity in the snake tribe Lam­pro­pel­tini (Ser­pentes: Col­u­bri­dae). Mol­e­c­u­lar Phy­lo­ge­net­ics and Evo­lu­tion, 52: 524-529.

Seigel, R., N. Ford. 1991. Phe­no­typic plas­tic­ity in the re­pro­duc­tive char­ac­ter­is­tics of an oviparous snake, Elaphe gut­tata: Im­pli­ca­tions for life his­tory stud­ies. Her­peto­log­ica, 47/3: 301-307.

Siev­ert, L., D. Jones, M. Puck­ett. 2005. Post­pran­dial ther­mophily, tran­sit rate, and di­ges­tive ef­fi­ciency of ju­ve­nile corn­snakes, Pan­therophis gut­ta­tus. Jour­nal of Ther­mal Bi­ol­ogy, 30/5: 354-359.

Sperry, J., C. Tay­lor. 2008. Habi­tat use and sea­sonal ac­tiv­ity pat­terns of the Great Plains rat­snake (Elaphe gut­tata emoryi) in cen­tral Texas. The South­west­ern Nau­tral­ist, 53/4: 444-449.

Stake, M., F. Thomp­son, J. Faaborg, D. Burhans. 2005. Pat­terns of snake pre­da­tion at song­bird nests in Mis­souri and Texas. Jour­nal of Her­petol­ogy, 39/2: 215-222.

Stew­art, J., T. Ecay, D. Black­burn. 2004. Sources and tim­ing of cal­cium mo­bi­liza­tion dur­ing em­bry­onic de­vel­op­ment of the corn snake, Pan­therophis gut­ta­tus. Com­par­a­tive Bio­chem­istry and Phys­i­ol­ogy, 139/3: 335-341.

Telford, S., J. But­ler, R. Telford. 2002. He­pa­to­zoon species (Api­com­plexa: He­pa­to­zoidae) of the corn snake, Elaphe gut­tata (Ser­pentes: Col­u­bri­dae) and the pigmy rat­tlesnake, Sistru­rus mil­iar­ius bar­bouri (Ser­pentes: Viperi­dae) in south Florida. The Jour­nal of Par­a­sitol­ogy, 88/4: 778-782.

Utiger, U., N. Helfen­berger, B. Schätti, C. Schmidt, M. Ruf, V. Ziswiler. 2002. Mol­e­c­u­lar sys­tem­at­ics and phy­logeny of old and new world rat snakes, Elaphe Auct., and re­lated gen­era (Rep­tilia, Squa­mata, Col­u­bri­dae). Russ­ian Jour­nal of Her­petol­ogy, 9/2: 105-124.

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

de Ma­g­a­l­haes, J., J. Costa. 2009. A data­base of ver­te­brate longevity records and their re­la­tion to other life-his­tory traits. Jour­nal of Evo­lu­tion­ary Bi­ol­ogy, 22/8: 1770-1774.