Corn Snake

Corn Snake
Conservation status
Not evaluated (IUCN 3.1)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Reptilia Order: Squamata Suborder: Serpentes Family: Colubridae Genus: Elaphe Species: E. guttata
Binomial name
Elaphe guttata Linnaeus, 1766
Synonyms
Pantherophis guttatus Utiger, et al, 2002

The corn snake (Elaphe guttata), or red rat snake, is a North American species of rat snake that subdue their small prey with constriction.^[1] The name "corn snake" comes from the fact that they have a maize-like pattern on their bellies that resembles corn. The Oxford English Dictionary cites this usage as far back as 1676. Corn snakes are found throughout the south-eastern and central United States. Their docile nature, reluctance to bite, moderate adult size 1.2 to 1.8 metres (3.9 to 5.9 ft), attractive pattern, and comparatively simple care make them popular pet snakes. In the wild, they usually live around 10-15 years, but may live as long as 23 years in captivity.^[2] Like all rat snakes, corn snakes are non-venomous.

Contents 1 Subspecies 2 Natural habitat 3 Diet 4 Reproduction 5 As pets 6 Variations 6.1 Color morphs 6.2 Compound morphs 6.3 Intergrades 6.4 Hybrids 7 References 8 External links

Subspecies

There are two subspecies of Elaphe guttata:

• The Common Corn Snake (Elaphe guttata guttata) lives in the southeastern United States, and is distinguished by having brownish-orange skin with orange/red saddles, the saddles having black borders, and usually a black and white underbelly.
• The Great Plains Rat Snake or Emory's Rat Snake (Elaphe guttata emoryi) is found in the United States from Nebraska to Texas, and into northern Mexico.

Natural habitat

Wild Corn Snakes prefer habitats such as overgrown fields, forest openings, trees, and abandoned or seldom-used buildings and farms, from sea level to as high as 6,000 feet. They can be found in the southeastern United States ranging from New Jersey to the Florida keys and as far west as Texas.

In colder regions, snakes hibernate during winter. However, in the more temperate climate along the coast they shelter in rock crevices and logs during cold weather, and come out on warm days to soak up the heat of the sun, a process known as brumation.^[3] During cold weather, snakes are less active and therefore hunt less.

Diet

Corn Snakes have a diet primarily consisting of rodents, mostly mice and rats, which they kill via constriction. They are proficient climbers and may scale trees in search of birds and bats. As litters of infant mice are difficult to find in nature, many neonate Corn Snakes are known to eat small lizards as their first meals, and anoles are the preferred choice. Some individuals retain these dietary tendencies well into adulthood.

Pet Corn Snakes are usually fed by their owners on a diet of commercially available rodents, predominantly mice, while younger and smaller specimens may eat live or dead rat or mouse pups of various sizes. Frozen mice are usually preferable, as live prey can possibly carry disease or injure the snake if it has not been raised on live prey.

Reproduction

Corn snakes usually breed shortly after the winter cooling. The male courts the female primarily with tactile and chemical cues, then everts one of his hemipenes, inserts it into the female, and ejaculates his sperm. If the female is ovulating, the eggs will be fertilized, and she will begin sequestering nutrients into the eggs, then secreting a shell.

Egg-laying occurs slightly more than a month after mating, with 12 to 24 eggs deposited into a warm, moist, hidden location. The eggs are oblong with a leathery, flexible shell. Approximately 10 weeks after laying, the young snakes use a specialized scale called an egg tooth to slice slits in the egg shell, from which they emerge at about 5 inches in length.

As pets

The Corn Snake was one of the first snakes to be kept in captivity by people, and remains one of the most popular.^[4] Large numbers are bred annually to ensure that there is a large captive-bred population, lowering the need to collect specimens from the wild. Cohabitation is inadvisable in captivity, as these are naturally solitary animals.

Keepers of Corn Snakes have emphasised a housing with no chance of escape. Corn Snakes are excellent escape artists and will often escape from any enclosure that is not properly fastened. More beginners lose their snakes to escapes than death.^[5] Corn snakes are good at climbing, squeezing out of very small holes, and can also use their bodies to push the screen top off of a poorly-fitted aquarium; pushing a temporarily-placed top off of a feeding container is not unheard of.

Hatchling Corn Snakes are often kept in a 5 to 10 gallon (19 to 38 L) aquarium or similar-sized plastic tub. As the snake grows, it requires more space. The minimum recommended size of housing for an adult is a 20 gallon (76 liter) tank. A 40 gallon (152 L) is a good recommended size and will provide the adult snake room to move. Corn Snakes become stressed in too large a cage with no hiding places; it is a good idea to use plants and many hiding spots in a large tank so that the snake will feel secure.

Since Corn Snakes, like all reptiles, cannot regulate their internal body heat, proper external heating is necessary for their health. A heat gradient from 70–75 °F (21–24 °C) on one end of the housing to 80–85 °F (26–29 °C) on the other is thought optimal to allow the snake to regulate its body temperature by moving from one part of the housing to the other, as necessary. Insufficient heat available in an enclosure at any point may lead to poor digestion, respiratory infections, and death, while excessive heat which the animal cannot escape, can cause neurological damage. Heat may be provided by a number of measures, including an under-tank heating pad (use at one end of the tank only), or one or more heat lamp(s), which should be attached to a thermostat to control temperature. Ceramic heat emitters may also be used in place of light bulbs, but if heat sources are not placed asymmetically, one part of the tank does not remain available for the animal to escape heaters.

Aspen or cypress shavings are often used to make bedding substrate, allowing the snake to burrow if it wishes; reptile carpet, newsprint, or paper towels also work. Cedar is toxic, so wood shavings containing cedar are not recommended. Feces are usually removed by spot cleaning, and periodically the tank is washed, disinfected, and bedding is replaced.

Juveniles may be fed newborn mice every 5 to 7 days; adults do well on large mice once every two weeks but may be fed weekly. A general rule for food size is that up to 1+¹⁄₂ the snake's body girth is acceptable. Corn snakes also readily take a larger number of smaller meals, and a 50-centimeter Corn Snake has been observed to swallow up to seven smaller-size "pinkie" rodent pups (less than the snake's girth), in rapid succession, in a span of less than five minutes. Thus, as a Corn Snake grows, smaller food items are not necessarily outgrown.

As a matter of good practice, feeding of large prey and handling should be separated as much as possible in snakes. Rapidity of feeding is facilitated if the snake is handled minimally so as not to be upset, before being transferred to the feeding container. After a snake swallows, its prey must pass its thorax and lung, along to its stomach in the mid-portion of its body (ordinarily less than a minute), and handling is avoided while this happens. After feeding and swallowing has been completed, all but minimal handling is avoided for a full 48 hours, until no lump can be seen in the snake's belly, to ensure proper digestion.

If substrates such as aspen or cypress mulch are used, the snake should be fed in a separate empty container, to prevent ingestion of chunks of substrate, which may lead to internal injury. Snakes do not require live prey (which may injure the snake, and which is considered animal cruelty in the UK) ^[6], and many corn snakes feed readily on pre-killed rodents which can be purchased as frozen from commercial suppliers, then completely thawed in warm water, prior to feeding. The food is not required to be warm (above room temperature) for the snake to eat it, but it must be completely thawed.

Non-feeders, snakes that have refused to feed more than twice, can be enticed into feeding by having the prey item slightly warmed, either by a heat lamp or soaked in water warm to the touch a few minutes before feeding. Microwaving prey items is not advisable as they can explode. Another technique called "Braining" where the skull of the prey item is punctured with a very clean needle and liquid from the skull exposed with forceps or tweezers. The smell of the liquid causes most snakes to feed.

Corn Snakes need a water dish and ideally will have access to clean water at all times. Corn Snakes swim well but generally do not seek water to swim in, but may well be found sitting in the water bowl. Corn snakes drink by dipping the end of their snouts in water and sucking up fluid with their cheeks. They need water every day although most people probably will not see the snake drinking.

Variations

After many generations of selective breeding, domesticated Corn Snakes are found in a wide variety of different colors and patterns. These result from recombining the dominant and recessive genes that code for proteins involved in chromatophore development, maintenance, or function. New variations, or morphs, become available every year as breeders gain a better understanding of the genetics involved.

Color morphs

• Normal or wildtype Corn Snakes are orange with black lines around red colored saddle markings going down their back with black and white checkered bellies. Regional diversity is found in wild caught Corn Snakes, the most popular being the Miami and Okeetee phases.
• Miami Phase (originates in the Florida wildtype) These are usually a smaller Corn Snake with some specimens having high contrasting light silver to gray ground color with orange saddle markings surrounded in black. Selective breeding has lightened the ground color and darkened the saddle marks. The "Miami" name, coined by Rich Zuchowski, now is considered an appearance trait. Many Miami Corn Snakes are difficult to start feeding as hatchlings, as they prefer lizards. Miami corns, unlike other varieties, will often readily accept anoles as food for life. This can simplify feeding for residents of Florida, but care should be taken to avoid introducing parasites from wild caught food.
• Okeetee Corns (classic corns, originate in the South Carolina wildtype) These snakes are characterized by deep red dorsal saddle marks surrounded by very black borders. The ground color varies with bright orange being popular amongst breeders. As with the Miami phase, selective breeding has changed the term "Okeetee" to an appearance rather than a locality. Some on the market originate solely from selectively breeding corns from the Okeetee Hunt Club.
• Candycane (selectively bred Amelanistic) These are amelanistic corns bred toward the ideal of red saddle marks on a white background. Some were produced using light creamsicle (emory/albino corn hybrids x corn) bred with Miami phase corns. Most candy canes develop orange coloration around the neck region as they mature and many labeled as candycanes later develop significant amounts of yellow or orange in the ground color. The contrast they have as hatchlings often fades with maturity.
• Reverse Okeetee (selectively bred amelanistic) an amelanistic okeetee Corn Snake which has the normal black rings around the saddle marks replaced with wide white rings. Ideal specimens are high contrast snakes with light orange to yellow background and dark orange/red saddles. Note: Albino Okeetees are not locale-specific okeetees, they are selectively bred amelanistics
• Fluorescent orange (selectively bred amelanistic) develop white borders around bright red saddle marks as adults on an orange background.
• Sunglow (selectively bred amelanistic) another designer albino corn that lacks the usual white speckling that often appears in most albinos, and selected for exceptionally bright ground color. The orange background surrounds dark orange saddle marks.
• Bloodred (selectively bred "Diffused") Corn Snakes carry a recessive trait (known as diffused) that eliminates the ventral checkered patterns. These originated from a somewhat unicolor Jacksonville and Gainesville, Florida strain of Corn Snake. Through selective breeding, an almost solid ground color has been produced. Hatchlings have a visible pattern that can fade as they mature into a solid orange red to ash red colored snake. The earlier bloodreds tend to have large clutches of smaller than average eggs that produce hard to feed offspring, though out-crossing with amelanistic and anerythristic corns hatchlings tend to be larger with fewer feeding problems.
• Crimson (hypomelanistic + Miami) are very light high contrast snakes with a light background and dark red/orange saddle marks.
• Anerythristic (anerythristic A, Sometimes called black albino) are the compliment to amelanism. The inherited recessive mutation of lacking erythrin (red, yellow, and orange) pigments produces a snake that is mostly black, gray and brown. When mature, many type A anerythristic Corn Snakes develop yellow on their neck regions. In 1984 a Type B anerythristic Corn Snake was caught in the wild; it is the ancestor of anerythristics missing the yellow neck regions. Similar snakes include: stonewashed -- copper or light brown saddle marks; charcoal (aka muted anerythristic, Pine Island anerythristic)-- type B anerythristic, very low contrast with shades of gray on white and black background.
  

  Anerythristic A Corn Snake
• Charcoal These snakes (sometimes known as anerythristic type 'B') can lack the yellow color pigment usually found in all Corn Snakes. They are a more muted contrast compared to Anerythristics.
• Caramel corns are another Rich Zuchowski engineered Corn Snake. The background is varying shades of yellow to yellow-brown. Dorsal saddle marks vary from caramel yellow to brown, and chocolate brown.
• Lavender Corn Snakes contain a light pink background with darker purple gray markings and burgundy eyes or lavender gray saddle marks on an orangish background. Variation with this same genetic strain are arguably called mocha, cocoa, and chocolate.
• Cinder reduced red pigment which becomes more like an anerythristic as they become adults.
• Kastanie This gene was first discovered in Germany. Kastanies hatch out looking nearly anerythristic but gain some color as they mature, to eventually take on a chestnut coloration.
• Hypomelanistic or rosy Corn Snakes carry a recessive trait that reduces the dark pigments causing the reds, whites, and oranges to become more vivid. Their eyes remain dark. These snakes range in appearance between amelanistic corns snakes to normals with greatly reduced melanin.
• Ultra Ultra is a hypomelanistic-like gene that is an allele to the Amelanistic gene. Ultra Corn Snakes have light grey lines in place of black.
• Ultramel (Ultra + Amelanistic) Ultramel appear a lot like Amels and Ultras but because they are heterozygous, two bred together will produce Amels, Ultras and Ultramels.
• Dilute is another melanin-reducing gene.
• Sunkissed is a hypo-like gene which was first found in Kathy Love's colony.
• Lava is an extreme hypo-like gene which was discovered by Joe Pierce and named by Jeff Mohr.
• Stargazing is caused by a simple-recessive genetic defect and is considered deleterious.^[7]

Compound morphs

There are tens of thousands of possible compound morphs. Some of the most popular are listed.

• Snow (Amelanistic + Anerythristic) As hatchlings this color variation is composed of white and pink blotches. These predominantly white snakes tend to have yellow neck and throat regions when mature. Light blotches and background colors have subtle shades of beige, ivory, pink, green, or yellow.
• Blizzard (Amelanistic + Anerythristic B) corns resulted from a type B anerythristic corn caught in 1984. Blizzards are a totally white snake with very little to no visible pattern.
• Ghost (Hypomelanistic + Anerythristic A) Corn Snakes are a hypomelanistic anerythristic (type A) snakes. They exhibit varying shades of grays, browns, and blacks on a lighter background. These often create pastel colors in lavenders, pinks, oranges, and browns.
• Phantom These are a combination of charcoal and Hypomelanistic.
• Pewter (Charcoal + Diffused) are silvery lavender with very slight blotches as adults.
• Butter (Amelanistic + Caramel) A two-tone yellow Corn Snake with bits of white between markings.
• Amber (Hypomelanistic + Caramel) corns are a hypomelanistic caramel snake with amber markings on a brownish background.

• Gold Dust (Ultramel + Caramel) Gold dust corns often have a more golden yellow than butters mixed with the grey lines rather than white.
• Plasma (Diffused + Lavander) Hatch out in varying shade of purple.
• Opal (Amelanistic + Lavender) look like blizzard corns once mature with pink to purple highlights.

Intergrades

• Root Beer are intergrades between a normal Corn Snake and a Great Plains Rat Snake (Emory's Rat Snake). Root Beer snakes look much like a sepia toned Corn Snake.
• Creamsicle are intergrades between an albino Corn Snake and an emory's rat snake/common corn cross. These snakes bring out the yellow and downplay the reds of the Corn Snake. Most are varying shades of yellow with darker yellow to orangish blotches. Clutches are generally smaller in number but produce larger, more vigorous hatchlings. Creamsicle with less emory background and increased amelanistic corn generally have lighter backgrounds and red to orange saddles (red creamsicle).
• Cinnamon is the hypomelanistic phase of the corn snake x Great Plains Rat Snake

Hybrids

• Jungle corns are hybrids using the Corn Snake and California Kingsnake (Lampropeltis getula californiae). These show extreme pattern variations taking markings from both parents -- sometimes looking very similar to one parent or the other. Although they are hybrids of different species, they are not sterile.

References

• Pantherophis replaces Elaphe. Utiger, Helfenberger, Schatti, Schmidtkutrjytdf(2002) Russian Journal of Herpetology 9(2): 105-124.
• Taxonomy citation
• Animal Facts: CORN SNAKE
• Taxonomy Citation - Herpetological Review [1]
• Stargazing Information Sheet [2]
• "IUCN Red List of Threatened Species". Retrieved on 2008-09-06.

External links

• herpFocus - video female laying egg.
• Pet Care Portal - A pet owners guide to keeping corn snakes in captivity.
• Ians Vivarium - Photo illustrated corn snake morph guide
• Comprehensive Corn Snake care information
• American Cornsnake Registry
• The Cornsnake Morph Guide - identification and genetic guide for collectors and breeders
• Corn snake care sheet
• Corn Snakes information