Snakes

There are 2,700 species of snake in the world. They come in 2,000 ways & colors.

There are snakes that lived 16,500feet (5,000meters) up in the mountains.

There are 100 species of dangerous & venomous snakes that can kill you.

The Giant Python could grow to 20feet (6meter). But 188 species are known to kill a human being.

There are 400 species of venomous snake. 235 of them can’t kill you.

In the pools the Anaconda can swim very well. They can strike up 23feet (7meters) per second. Imagine I can only strike 4feet (1.2meter) per second.

The Black Mamba can move at speeds of 18mph (24kph).

You don’t think the sidewinder is slow. It can move at 16-20kph (12-14mph). The Green Mamba can also move at 19- 21kph (13-15mph).

The Slowest snake is the Rough Scaled snake ( a kind of tiger snake) it moves at 3-7kph (1-3mph).

The Yellow Rat snake can be 7feet (2.1meters) long.

The African Python grew to 7.8meters (25feet 8inch). The record length of African Pythons is 9.78meters (31feet) long. But the Green Anaconda which weighs 400kilograms (900pounds) record length is 12.2meters (37feet 4inches).

The world’s longest snake goes to Reticulated Python it can grow to an amazing 17.8meters (59feet 2inches). But true stories of 190feet (53meters) anaconda from the wild heart of Amazon Basin.

The Puff Adder 1 kind of venomous snake, can strikes 3/4 times a second (18feet per second).


REPTILES:-Snakes are reptiles. Reptiles are cold-blooded so they must warm themselves in the sun or on rocks. Snakes have skin covered with scales and most lay eggs. Some snakes hold their eggs inside until they hatch. Snakes have no legs and no ears

PREDATORS OR PREY:-Snakes are skilled predators. How would you catch prey without arms or legs? Venomous snakes have poison to inject in their prey. The venom keeps small prey still so the snake can grab it with its mouth and swallow it whole. This is a helpful adaptation for snakes. Snakes help the balance of nature by eating prey that reproduces frequently, everything from earthworms to rabbits. Snakes also eat eggs. Snakes are especially important in the control of mice and rats.

Venomous Snakes in Texas

There are four kinds of venomous snakes in Texas: coral snakes, copperheads, cottonmouths (water moccasins) and rattlesnakes.

Coral Snakes



Only one species of coral snake is native to Texas. The coral snake is shy and rarely seen. It has, in order, red, yellow and black colors. The coral snake has a small mouth, and is usually not aggressive. Its bites are dangerous, but very rare.

Other, harmless snakes have similar colors in a different order. The rhyme "red and yellow kill a fellow" can help you remember that the coral snake's red and yellow colors touch, but the harmless milk snake has red touching black.

What is a Pit Viper?

A pit viper is a type of venomous snake. Copperheads, cottonmouths and rattlesnakes are called pit-vipers because they have a pit near each nostril which is highly sensitive to heat. This pit helps the snake in locating warm-blooded prey.

Copperheads

Copperhead snakes have bands of gray and/or brown with a copper-colored heard. They blend in with leaf-covered forest floors and it's possible to stare right at a copperhead without seeing it! Copperheads bite rather than strike. Because they are so well camouflaged, most bites occur when a snake is accidentally picked up or sat or laid on. Always use care when picking up or flipping over logs, boards, old tin or other items where copperheads may be resting.

Cottonmouths

The cottonmouth, or water moccasin, rarely strays far from water. It can be found in marshes, swamps, ponds, lakes, ditches, and canals in East and Central Texas and along the Gulf coast. It is a stubby, muscular snake and can grow to nearly six feet. When threatened, it will open its mouth to show its fangs. The inside of its mouth is white and reminded people of cotton, hence the name cottonmouth. They eat frogs, fish an small animals. These snakes can be very defensive and sometimes aggressive. They can bite underwater. Swimmers, bathers and anglers on river banks should always keep an eye open for these snakes.

Rattlesnakes

The Western Massasauga lives in prairies from the Gulf Coast up to the Panhandle

The Timber Rattlesnake lives in East Texas.

Western Diamondback lives in North, Central, South and West Texas.

Nine kinds of rattlesnakes are found in Texas, including the massasauga. Rattlesnakes usually "rattle" before striking, but if they are totally surprised, they may strike before rattling. Most of the rattlesnakes are active at night, when they hunt for prey such as mice, rats and rabbits.

How Snakes Work

Introduction to How Snakes Work.




­In the more than 130 million years since they appeared, snakes haveevolve into a highly versatile­ vertebrate, boasting the ability to climb straight up, dart through water and, in some species, even fly -- all without limbs. Combine this mobility with a worldwide presence and a sometimes-deadly bite, and snakes can quickly become the stuff of myths.


Snake Basics

­ There are 2,700 known snake species, and the reptiles all share the following characteristics:
  • They have thin, linear and limbless bodies.
  • They are meat-eaters (carnivores).
  • They are cold-blooded (ectothermic), meaning their inner temperature varies with the temperature in the environment.

Snakes look like legless lizards for a reason -- the two reptiles make up the order Squamata, which is divided into the suborders Sauria for lizards and Serpentes (or Ophidia) for snakes. Because of their long shape, snakes' organs are arranged linearly, but they are otherwise similar to those of other vertebrates, including people. The bone-encased brain and sensory organs are contained in the head, and snakes have almost all the senses people do -- with a few interesting modifications:

  • Hearing - Although snakes are not equipped with outer ears like people, sound waves from the air hit their skin and are transferred from muscle to bone. When the sound reaches the ear bone beneath the skull, it sends vibrations to the inner ear, and the sound is processed by the brain.

  • Sight - Snakes do not see colors, but their eyes are equipped with a combination of light receptors: rods that provide low-light but fuzzy vision, and cones that produce clear images. The complexity of the eyes varies among species because of their different lifestyles. For instance, snakes that live primarily underground have smaller eyes that only process light and dark, but snakes that live above ground and hunt by sight have crystal-clear vision and good depth perception. Some species, specifically boas and pythons, have a second visual tool: Pit organs on their heads see heat sources in their surroundings like infrraded surrondings-- an effective ability for nocturnal hunters of warm-blooded animals.


    Photo courtesy Saint Louis Zoo
    Annulated boa

  • Smell - Like humans, snakes breathe airborne smells into nasal openings that lead to an olfactory chamber for processing; but snakes have a secondary system, as well. When a snake flicks its tongue, it is gathering odor particles for transfer to two fluid-filled sacs at the roof of the mouth -- Jacobson's organs -- that lead to a second, smaller olfactory chamber. The tongue is used only to assist in this process; snakes do not have a sense of taste.


The digestive tract runs nearly the entire length of the body and includes the mouth, esophagus, stomach, small intestine, large intestine and anus -- all stretchable to digest prey larger than a snake's diameter (See Feeding section). When the snake's mouth is full, it has to extend its trachea (breathing tube) below the food and out in order to keep breathing. Snakes do not have a diaphragm like people do, so they circulate air in and out of the lungs by narrowing the rib cage to push air out and then widening it again to create a vacuum to suck air in. After each breathing cycle, snakes experience apnea -- a stop in breathing -- that lasts from a few seconds to as long as a few minutes. To process the oxygen, all snakes have an elongated right lung; many also have a smaller left lung, and a few even have a third lung along the trachea.

Two-headed Snakes
Two-headed snakes are less like the terrifying multi-headed monsters of myth and more like conjoined twins. Within the mother snake, an embryo begins to split to create identical twins, but the process does not finish, leaving part of the snake split and the other parts conjoined.

Unlike the mythical creatures, whose multiple heads make them significantly more dangerous, two-headed snakes rarely survive in the wild. With two heads, the senses are duplicated: When they sense prey, the heads will fight over which one gets to eat it. To make matters worse, if one head catches the scent of food on the other, it will try to eat its other head.


Photo courtesy Saint Louis Zoo
In the early 1980s, a two-headed bull snake was donated to the Saint Louis Zoo. It grew to be about 3 feet long and lived two and half years, an unsually long life span for two-headed animals. The snake had a dominant right head, and keepers had to put an index card between the two heads when feeding the snake so it didn't fight with itself.

Snake Structure & Growth

Snakes range from 4 inches (10 cm) to more than 30 feet (9 meters) in length. Hundreds of tiny vertebrae and ribs span this distance and connect to each other through an intricate system of muscles, creating unrivaled flexibility (See Getting Around section). An extremely elastic skin attaches to the muscles and is covered with scales made of keratin -- the same substance as human fingernails. The scales are produced by the epidermis, the outer layer of skin. As the snake grows, the number and the pattern of its scales stay the same, although a snake's scales are shed many times over the course of its life.


Photo courtesy U.S. National Oceanic and Atmospheric Administration
Molted snake skin

Unlike people, who shed worn-out skin constantly in tiny pieces, snakes shed all of their scales and outer skin in one piece during a process called molting. When the skin and scales start to wear down from time or injury, the epidermis begins to create new cells to separate the old skin from the developing inner layer. The new cells liquefy, making the outer layer soften. When the outer layer is ready to shed, the snake scrapes the edges of its mouth against a hard surface, such as a rock, until the outer layer begins to fold back around its head. It continues scraping and crawling until it is completely free of the dead skin. The molting process, which takes about 14 days, is repeated after anywhere from a few days to a few months.

Like people, snakes grow quickly until they reach maturity, which can take one to nine years; however, their growth, though much slowed after maturity, never stops. It's a phenomenon known as indeterminate growth. Depending on the species, snakes can live from four to more than 25 years.




Sidewinder snake (a.k.a. "horned rattlesnake")

Snake Movement: Getting Around

ARE U FOUND OF SNAKES

The key to snakes' agility -- hundreds of vertebrae and ribs -- is closely related to the key to their locomotion: ventral scales. These specialized rectangular scales line the underside of a snake, corresponding directly with the number of ribs. The bottom edges of the ventral scales function like the tread on a tire gripping the surface and propelling the snake forward.

Snakes have four basic methods of movement:


 

  • Serpentine - This S-shape movement, also known as undulatory locomotion, is used by most snakes on land and in water. Starting at the neck, a snake contracts its muscles, thrusting its body from side to side, creating a series of curves. In water, this motion easily propels a snake forward because each contraction pushes against the water. On land, a snake usually finds resistance points in the surface -- such as rocks, branches or dents -- and uses its scales to push on the points all at once, thrusting the snake forward.


    Speckled rattlesnake using rocks as resistance points

  • Sidewinding - In environments with few resistance points, snakes may use a variation of serpentine motion to get around. Contracting their muscles and flinging their bodies, sidewinders create an S-shape that only has two points of contact with the ground; when they push off, they move laterally. Much of a sidewinding snake's body is off the ground while it moves.

    Can Snakes Fly?
    There are five different species of "flying" snakes. These venomous, tree-dwelling snakes are found in Sri Lanka and Southeast Asia.

    They hang from a high branch and swing themselves into the air. They then flatten their bodies by widening their many ribs and use side-to-side, S-shaped motions to keep themselves in the air. These snakes cannot fly upward but can glide for a good distance.

  • Caterpillar - A much slower method of movement is caterpillar or rectilinear locomotion. This technique also contracts the body into curves, but these waves are much smaller and curve up and down rather than side to side. When a snake uses caterpillar movement, the tops of each curve are lifted above the ground as the ventral scales on the bottoms push against the ground, creating a rippling effect similar to how a caterpillar looks when it walks.

  • Concertina - The previous methods work well for horizontal surfaces, but snakes climb using the concertina technique. The snake extends its head and the front of its body along the vertical surface and then finds a place to grip with its ventral scales. To get a good hold, it bunches up the middle of its body into tight curves that grip the surface while it pulls its back end up; it then springs forward again to find a new place to grip with its scales.
Anaconda: King of the Jungle

The heaviest snake in existence is also one of the most prolific swimmers. The anaconda, which can weigh as much as 550 pounds (250 kg) and measure more than 12 inches (30 cm) in diameter, usually lives near slow-moving rivers and swamps in the jungles of South America. It spends most of its time in the water, where it can move much faster than on land, using its powerful muscles to propel itself through the water using serpentine locomotion.

Like an alligator the Anaconda's eyes and nostrils are located on the top of its head so it can see prey and breathe while keeping the rest of its body hidden beneath the surface. When it does go completely underwater, the anaconda can hold its breath for up to 10 minutes. These snakes copulate and give birth in the water, as well (See Snake Sex section). To feed, the non-venomous anaconda uses constriction to suffocate and often drown its prey (See Feeding section).

Snake Digestion: What a Snake Eats

SNAKES ARE WONDERFUL CREATURES

Although snake species have different methods of finding and catching prey, all snakes eat in basically the same way. Their amazingly expandable jaws enable them to prey on animals of much larger size -- and swallow them whole. Whereas the upper jaw of a human is fused to the skull and therefore unable to move, a snake's upper jaw is attached to its braincase by muscles, ligaments and tendons, allowing it some front-to-back and side-to-side mobility. The upper jaw connects to the lower jaw by the quadrate bone, which works like a double-jointed hinge so the lower jaw can dislocate, allowing the mouth to open as wide as 150 degrees. Also, the bones that make up the sides of the jaws are not fused together at the front like the human chin, but instead are connected by muscle tissue, allowing the sides to separate and move independently of one another. All of this flexibility comes in handy when a snake encounters prey bigger than its head -- its head can stretch to accommodate it.


Once a snake is ready to eat, it opens its mouth wide and begins to "walk" its lower jaw over the prey as its backward-curving teeth grip the animal -- one side of the jaw pulls in while the other side moves forward for the next bite. The snake drenches the prey with saliva and eventually pulls it into the esophagus. From there, it uses its muscles to simultaneously crush the food and push it deeper into the digestive tract, where it is broken down for nutrients.

Even with all of these advantages, eating a live animal can be a challenge. Because of this, some snakes have developed the ability to inject venom into prey to kill or subdue the animal prior to eating it. Some venom even gives the digestion process a kick-start. Snakes with this effective tool must have an equally effect way of getting the poison into an animal's system: fangs.

At the front or back of their upper jaw, venomous snakes have two sharp teeth that are hollowed out to allow the poison to pass through. Once a snake strikes, inserting these teeth into its prey, venom is squeezed from a gland under each eye into the venom duct -- where it passes more glands that release compounds thought to make the venom more effective -- and out through the venom canal in the fangs.


In non-venomous, constrictor snakes, the teeth are stationary; in snakes with long (grooved) fangs, the teeth fold backward into the mouth when not in use -- otherwise, the snake would puncture the bottom of its own mouth.

Although the venomous snake species -- which make up only one fifth of all snakes -- each have their own special brew, the following are the three most important types of toxins found in snake venom:

  • Neurotoxins - Affect the nervous system by seizing up the nerve centers, often causing breathing to cease
  • Cardiotoxins - Deteriorate the muscles of the heart, causing it to stop beating
  • Hemotoxins - Cause the blood vessels to rupture, resulting in widespread internal bleeding

Boa Constrictor: The Main Squeeze

Photo courtesy Saint Louis Zoo
Emerald tree boa

The boa constrictor is related to the anaconda, but the boa stays out the water as much as the anaconda stays in it.

This non-venomous South and Central American snake, which can weigh more than 60 pounds (27 kg) and grow to nearly 10 feet (3 meters), uses the process of constriction to suffocate and kill its prey before eating it whole. It has been known to constrict and eat monkeys, rodents and other reptiles, often using its prehensile tail to hang from trees and drop down on prey.


Some venom may also include agglutinins, which make the blood clot, or anticoagulants, which make the blood thin. Most snake venom makes use of several of these compounds for a deadly combined effect. A few snakes squeeze the life out their prey in another way -- constriction. Once a snake has the animal firmly in the grip of its jaws, it loops its body in coils around the prey. When the animal exhales, letting the air out of its body cavity, the snake contracts its powerful system of muscles to tighten the coils, squeezing the body so that the animal cannot breathe in again. According to a Carnegie Mellon University study in 2002, depending on its size, a constrictor can apply 6 to 12 pounds of pressure per square inch. Although this pressure suffocates the prey by compressing the lungs, it can also have the same effect on the heart, speeding up death significantly.

Snake Sex

One might think having no limbs would put a damper on the love life, but not for snakes. When a female snake is ready to mate, she begins to release a special scent (pheromones) from skin glands on her back. As she goes about her daily routine, she leaves an odor trail as she pushes off resistance points on the ground. If a sexually mature male catches her scent, he will follow her trail until he finds her. The male snake begins to court the female by bumping his chin on the back of her head and crawling over her. When she is willing, she raises her tail. At that point, he wraps his tail around hers so the bottoms of their tails meet at the cloaca -- the exit point for waste and reproductive fluid. The male inserts his two sex organs, the hemipenes, which then extend and release sperm. Snake sex usually takes under an hour, but it can last as long as a whole day.

Red-sided garter snakes in mating ball
Red-sided garter snakes in mating ball.

Female snakes reproduce about once or twice a year; however, the methods of birth vary among species. Some snakes give birth to live young (from one to 150 at a time), while others lay eggs (from one to 100 at a time); some even combine these methods by holding eggs internally until they hatch, and the babies are born live. For the most part, female snakes do not sit on their eggs like a hen, but in some cases they will protect their eggs (and their young) for a few days after they leave the mother's body.


RED BELLY SNAKE




Status

PROTECTED. It is illegal to kill or collect this species by law in Iowa. Redbelly snakes are common but secretive in Iowa.

Redbelly snakes, red phase and grey phase
Redbelly snakes, red phase and grey phase
 

Description

This is Iowa's smallest species of snake measuring 7-10 inches long (Conant and Collins, 1991). It is non venomous. Generally speaking, there are two color phases of this snake and even these are subject to variation. One phase is dark brown to light tan dorsally with a single light mid dorsal stripe. The other phase is a shade of gray dorsally with four black or rust red stripes running lengthwise down the snake.

The following characteristics are shared by both: the belly is usually bright red or pink with no markings. There may or may not be three pale spots on the nape. The scales are keeled and the anal plate is divided. The bright red belly with no markings and the presence of dorsal striping is sufficient to distinguish it from other small Iowa snakes.

Red belly snake, venter
Redbelly snake, venter
 

Subspecies

There are three subspecies of the redbelly snake, two of which supposedly occur in Iowa. The northern redbelly snake, Storeria occipitomaculata occipitomaculata, differs only by the presence of three light spots on the nape. The other, the Black Hills redbelly snake, Storeria occipitomaculata pahapsae, lacks these spots. These subspecies intergrade throughout their Iowa range. Furthermore, these subspecies are weakly defined and both forms are found in the same populations outside the intergrade zone.

Range

The redbelly snake snake seems to occur through out the northeastern half of Iowa.

County records for  the redbelly snake in Iowa
County records for the redbelly snake in Iowa
 

Habitat

This snake is generally considered a woodland snake, but it is also found in dry sandy habitats. It is often found near marshes, lakes, or other water sources.

Habits

This small snake may be found under flat objects or crawling across woodland trails in the evening or at night. Sometimes they may be found in garages or while moving a woodpile. Great numbers of these snakes are seen in the fall as they migrate to their hibernaculums. They make no attempt to bite when handled, but they may release musk which is relatively mild compared to other species of snakes. The redbelly snake is secretive and their main defense from predators is hiding under rocks, logs or leaf litter. They hibernate underground in rock crevices, abandoned ant mounds, and in burrows dug by other animals. They breed in spring. Five to eight young are born alive in late summer and are very small, only 3 1/2 inches long.

Redbelly snake, Storeria occipitomaculata
Redbelly snake, Storeria occipitomaculata
 

Food

The redbelly snake eats slugs, earthworms, and insect larvae. It is usually very difficult to get these snakes to consume anything other than slugs without using scent-transfer techniques.

Redbelly snake, Storeria occipitomaculata
Redbelly snake, Storeria occipitomaculata
Redbelly snake, Storeria occipitomaculata
Redbelly snake, Storeria occipitomaculata


EASTERN  GARTER SNAKE  

Copyright, Jeff LeClere

The Eastern Garter Snake is one of our most common snakes. It grows up to four feet long. It's color patterns can vary, but it almost always has three yellow stripes. Usually there is a checkerboard pattern of dark spots between the stripes.

These snakes are usually found near water or moist places, including marshes, streams, damp woods, wet meadows, parks, gardens, weed patches, farms, and forest edges.

Garter snakes are very active, and can be found day or night, though they're most active during the day. They are usually seen among vegetation (plants).

Martin C. Schmidt, Ph.D.

Copyright 2001, Troy Bartlett (http://troyb.com/photo/index.htm)

Eastern Garter Snakes hunt or bask during the day. Basking is what cold-blooded animals, like reptiles, do to get warm. Their bodies need the heat of the sun to digest their food. Snakes usually bask somewhere that gives them a place to quickly hide, such as rocks, logs, or mammal burrows.

Garter snakes have many types of prey, including: frogs, toads, salamanders, earthworms, small fish, tadpoles, mice, bird eggs, slugs, crayfish, leeches, insects, and small snakes. They also eat carrion, and often get run over by cars when they try to eat some small dead animal (such as a frog) off a road.

Copyright, Mike Pingleton

Eastern Garter Snakes mate from late March to early May. Sometimes when several males find a female at the same time, they form a "breeding ball." A breeding ball is when snakes wrap themselves around each other, trying to mate. See the picture of a garter snake breeding ball further down the page.

Females do not lay eggs, like most snakes, but instead give birth to live young. Each baby snake is five to nine inches long. Over 50 young can be born together. Most of them will not survive as young snakes have many predators.

Predators of garter snakes include: hawks, skunks, raccoons, Virginia Opossum, larger snakes, and Bullfrogs.

Copyright 2001, Troy Bartlett (http://troyb.com/photo/index.htm)

Copyright, Mike Pingleton

In Winter, garter snakes hibernate, usually with other garter snakes, and sometimes with other species. Winter dens may be under large rocks or inside mammal burrows.

Eastern Garter Snakes are the first snakes to become active in Spring. They have even been seen crawling over snow.

Garter snakes are good swimmers, but are not as good at climbing as some other snakes. They spend most of their time on the ground or in low shrubs and other plants.

If attacked, a garter snake will release a bad-smelling odor. They also bite.

Garter snakes can live up to 10 years.





Prairie RattlesnakeThis e-mail address is being protected from spam bots, you need JavaScript enabled to view it

Status

Prairie Rattlesnake, Crotalus viridis, Plymouth County, Iowa
Prairie Rattlesnake, Plymouth County, Iowa
 

ENDANGERED. It is illegal to kill or collect this species by law in Iowa. Known from only a few locations in northwestern Iowa. Please report this snake to usThis e-mail address is being protected from spam bots, you need JavaScript enabled to view it or the DNR, especially if found outside of Plymouth County.

Description

This is a large, venomous Iowa species that is very heavy bodied and measures from 35 to 45 inches in length; the record is 57 inches (Conant and Collins, 1991). Prairie rattlesnakes have a diamond shaped head which is set off from the relatively thin neck. The pupils of the eyes are elliptical in bright light and there is a heat-sensitive pit between the eye and nostril on both sides of the head. Ground color consists of varying shades of brown, from tan to greenish, to dark brown. There are darker blotches down the back, and smaller spots on the sides. The belly is usually light yellow or cream and unmarked except for darker stippling on some specimens. The tail is ringed with a tan rattle at the end. The rattle at the end of the tail will distinguish this snake from all others in its Iowa range. The scales are keeled and anal plate is single. The subcaudals are single (instead of divided as in all harmless Iowa snakes). Young are patterned the same as the adults and some specimens may have a lot of white outlining the blotches. They are 7 to 13 inches in length at birth.

Prairie Rattlesnake, Crotalus viridis, Plymouth County, Iowa
Prairie Rattlesnake, Plymouth County, Iowa
 

Subspecies

The prairie rattlesnake, Crotalus viridis viridis, is the only subspecies found in Iowa.

Range

Although common in South Dakota and in other states to the west, this species barely enters Iowa. It is known from only one population in the loess hills in western Plymouth County. It may have had a slightly larger range in the past; recent reports suggest relict populations re-establishing or movement of the existing population.

County Records for the Prairie Rattlesnake in Iowa
County Records for the Prairie Rattlesnake in Iowa
 

Habitat

Prairie rattlers are found in rolling prairies, grasslands, pastures, and other open prairie areas. Klauber (1997) states that the most common habitat utilized by C. v. viridis are the grassy plains, the country of the prairie dog and the burrowing owl.

Habits

These snakes seem to emerge from hibernation in late April and early May. Many may be found hibernating together and groups may be seen basking outside the dens in spring and fall. Klauber (1997) gives a detailed summary of dens from South Dakota. They are located on south facing slopes in rocky crevices. In the absence of such structure, they use deep burrows dug by prairie dogs and badgers. These burrows are favored on slight south facing elevations for warmth. During the summer, they move into home ranges. As with many snakes, they are diurnal in the spring and fall, but shift to nocturnal activity during warmer summer months.

Prairie Rattlesnake, Plymouth County, Iowa
Prairie Rattlesnake, Plymouth County, Iowa
 

Prairie rattlesnakes may not mate immediately following emergence from hibernation as males are reported to locate females away from dens (Rubio, 1998). Males search for females in the latter part of the active season; this species mates from mid-July to early September (Ernst, 1992). Gravid females do not eat during the gestation period and spend most of their time basking. Females give birth from August to early October (Diller and Wallace, 1984). Litter sizes ranges from 6 to 16 young. Unlike Iowas other venomous species, the prairie rattlesnake is pugnacious; coiling and striking with little provocation. This is how many have reacted when I have found them, including specimens from Plymouth County. They will flee if given the opportunity, a bite will not occur if they are left alone when found. Sometimes they sit quietly blending in with the grass, but they are more apt to rattle.

Prairie Rattlesnake with young, Plymouth County, Iowa
Prairie Rattlesnake with young, Plymouth County, Iowa
 

A prairie rattlesnake is easy to identify from other harmless species, even though they are patterned the same. A prairie rattlesnake will hold its rattle high off the ground when it rattles making the rattle very obvious. A harmless snake will vibrate its tail to make a similar sound, but the tail must be held close to the ground to produce any noise; not high in the air like the rattlesnake. This snake is very rare in Iowa and I know of no deaths caused by this snake. Agriculture and human interference have reduced the numbers or this already rare snake. Fortunately, the areas where this snake is now found is difficult to farm and some areas are protected. A prairie rattlesnake found outside of Plymouth County in Iowa should be reported!

Food

Prairie rattlesnakes eat mammals, birds, and ground nesting birds eggs. Mice, young prairie dogs, and cottontail rabbits are common foods. Among the birds, the highest ranking found in Klauber (1997) were meadow larks. Small reptiles and frogs may be eaten as well. Prey is envenomed with a quick bite and released. The strike is aided by the heat sensitive pits present in all of Iowa's venomous snakes. Prey is then tracked using scent (Ernst, 1992).

Prairie Kingsnake - Lampropeltis calligaster


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Status

PROTECTED. It is illegal to kill or collect this species by law in Iowa. These snakes are common in the southern two tiers of counties. We are looking for any reports north of those counties.

Prairie King Snake, Lampropeltis calligaster
Prairie King Snake
 

Description

A medium sized Iowa snake that is 30 to 42 inches in length (Conant and Collins, 1991). It is nonvenomous. The prairie kingsnakes general coloration is quite variable. Some specimens can be beautifully light colored, having a light gray or brown ground color and darker body blotches. The blotches are usually brown, but some snakes may have reddish or greenish blotches. Some, especially older specimens, may lose the spots and develop four longitudinal stripes down the back. This appears to be rare in Iowa, however. There are two rather oblong blotches behind the head; and an alternating row (sometimes two) of dark lateral spots on the sides. These lateral spots vary in size, but are never as big as the dorsal blotches.

Prairie King Snake, Lampropeltis calligaster
Prairie King Snake
 

The belly is cream or yellowish with brown checkers scattered randomly about the venter. There is often a dark line from the eye to the angle of the jaw, and there may be dark sutures on the lips. The prairie kingsnakes scales are smooth and the anal plate is single. The prairie kingsnake closely resembles the fox snake. Fox snakes have weakly keeled scales, a divided anal plate, and less markings on the head.

Subspecies

The prairie kingsnake, Lampropeltis calligaster calligaster, is the only subspecies found in Iowa.

Range

Prairie kingsnakes are found in the southern third of Iowa.

County Records for the Prairie Kingsnake in Iowa
County Records for the Prairie Kingsnake in Iowa
 

Habitat

These snakes utilize a wide variety of habitats. They are found in prairies, (including sand prairies), open grassland, fields, pastures, in ditches along cultivated field and roads, woodlands, and some stream valleys and blufflands. They are most common in grasslands along forest edges, and are only occasionally found in blufflands or sand prairies. They also do not appear to be found deep in heavy woodlands very often.

Habits

Prairie kingsnakes are active from April to October in Iowa. They are diurnal in the spring and fall becoming largely nocturnal in summer. This is the most common large constricting snake in southern Iowa. I find that prairie kings are the most commonly road-killed snake in this area.

I have noticed a rather interesting distributional relationship between prairie kingsnakes and fox snakes in Iowa. While the fox snake is one of the most common species in the northern two thirds of the state, the prairie kingsnake seems to replace it in the south. However, the fox snake still has a stronghold in the Mississippi and Missouri River Valleys. I rarely find both species in the same area, but I have seen DOR specimens of both species within a few hundred feet of one another in Louisa County. Undoubtably this occurs in other areas as well, but in south central Iowa, there is an obvious reduction in the number of fox snakes and an increase in the number of prairie kingsnakes. Minton (1972) mentions the same relationship between these species in Indiana. The prairie kingsnake utilizes the same habitats as the fox snake and may be slightly more diverse in habitat usage. The prairie kingsnake is certainly more diverse in prey acceptance than the fox snake, and in this respect gives the prairie kingsnake the advantage over the fox snake.

Prairie kingsnakes are active snakes that wander a great deal, but they are still somewhat secretive. They are often seen on the roads in the morning or at dusk, and later after sunset in warm summer months. Individuals are rather passive when picked up, but a few will bite. They also release musk and vibrate their tails when agitated.

Prairie kingsnakes mate soon after emergence from their hibernaculums(Johnson, 1992). The male will bite the head or neck of the female during courtship and keep a hold during copulation. Collins (1993) reports egg laying in June or July. The average clutch size is 11 (Minton, 1972). The eggs hatch in September. The young look like adults, but are often more reddish in overall coloration; some specimens retain this color, but most will become much darker as adults.

Food

Prairie kingsnakes are dietary generalists and feed on a wide variety of prey. Mammals, birds, birds eggs, snakes, lizards, frogs, and reptile eggs have been reported as food. Prairie kings, like other kingsnakes, will eat venomous snakes. They are immune to the venom of North American venomous snakes and such snakes will use other methods to escape kingsnakes. Instead of striking, the the venomous species will throw loops of coils at the kingsnake in an attempt to bat the head and make a quick escape. Prairie kingsnakes are even known to consume other prairie kingsnakes (Smith, 1961). Kingsnakes are constrictors; killing their prey by suffocation before devouring it.

Prairie kingsnakes are often found around farms and barns. They are looking for mice and other prey. Constricting snakes are very beneficial to farmers. Unfortunately, many people are ignorant of this fact and kill the snake believing it to be venomous. This is foolish; because of the snakes broad diet, the kingsnake will not only rid the farmer of mice, but this harmless species will actually rid the farmer of any venomous species that happen to be around as well.

Plains Garter Snake - Thamnophis radix


Status

UNPROTECTED. Garter snakes are afforded no protection in Iowa. Plains garter snakes are found statewide..

Plains Gartersnake, garter snake, Thamnophis radix
Plains Garter Snake
 

Description

The plains garter snake is a medium sized Iowa snake measuring 14 to 43 inches in length (Conant and Collins, 1991). Plains garter snakes are the most heavy bodied of all Iowa garter snakes. It is non venomous and can be more docile than the eastern garter snake. The ground color is light brown to black with two alternating rows of black spots. Some specimens have an olive green background color in which the spots stand out especially well. Some populations have bright red pigment on the sides. I have seen reddish specimens in Linn and Mills Counties.

Lateral stripe on 3rd and 4th scale rows
Lateral stripe on 3rd and 4th scale rows
 

Plains garters have three longitudinal stripes. The dorsal stripe is usually yellow or orange; some have an orange stripe anteriorly that changes to yellow before mid body and remains yellow to the tip of the tail. The lateral stripes are cream to yellow and are located on the third and fourth scale rows. There is usually a row of black spots below the lateral stripes at the edge of the ventral scales. The belly may be white, yellowish, or bluish. The head is brown or black with one or two small yellow dots near the parietals scales atop the head (these may be absent). There dark black bars on the labial scales. The scales are keeled and the anal plate is single.

The very similar eastern garter snake has the lateral stripes on rows two and three. Ribbon snakes are more slender, have a longer tails, and have white, unmarked labials.

Unusual red specimen, Thamnophis radix, gartersnake
Unusual red specimen of the Plains Garter Snake
 

Subspecies

I choose to recognize no subspecies of the plains garter snake, Thamnophis radix. There were formerly two weakly defined subspecies of the plains garter snake, both found in Iowa. The eastern plains garter snake, Thamnophis radix radix, was characterized by possessing 19 scale rows on the neck and 154 or fewer ventral scales. The western plains garter snake, Thamnophis radix haydeni, differed by having 21 or more scale rows on the neck and 155 or more ventral scales. There were apparently slight differences in coloration and the western race has smaller dorsal spots, but this was certainly not always consistent. These two subspecies reportedly intergraded heavily in Iowa so specimens resembling either subspecies would have been found anywhere in Iowa. Additionally, the the most striking, obvious geographical morphological changes occur much farther west than the described subspecies ranges showed.

Range

The plains garter snake is found statewide in Iowa.

County Records for the Plains Garter Snake in Iowa
County Records for the Plains Garter Snake in Iowa
 

Habitat

The plains garter snake is one of Iowa's most common snakes. They occur almost anywhere there is adequate food and shelter. They are extremely adaptable to environmental changes like the eastern garter snake. Unlike the eastern garter snake, however, the majority of plains garters prefer drier habitats, though a few individuals may be found at the waters' edge. Open plains or grasslands on forest edges are favorite natural haunts. City parks, vacant lots, farmlands, or suburban backyards are also utilized.

Habits

This is a diurnal, active snake that is usually much less aggressive than the eastern or red-sided garter snake. Instead of biting, it often expels a foul smelling musk and excretement to dissuade enemies. If cornered, it may hide its head under its coils, raise its tail in the air, and slowly wag its tail back and forth. Garter snakes are active thermoregulators and will alternately hunt and bask throughout the day. They take refuge underneath logs, rocks, boards, and in mammal burrows.

Thamnophis radix, plains gartersnake
Plains Garter Snake, Iowa

 

Garter snakes breed in the spring and the young are born alive in late summer or autumn. There may be 10-70 or more in a litter and are 5-8 inches irn length. They may hibernate with other species of snakes and use any place they can get below the frost line. Road embankments, mammal burrows, and basements are common hibernaculums.Young plains garter snakes may hibernate with redbelly and green snakes in abandoned ant mounds.

Food

Plains garter snakes are voracious feeders and will eat anything they can catch and swallow, especially when warm. Earthworms, fish, frogs, toads, salamanders, mice, and birds eggs are consumed. These snakes may eat carrion. They eat their prey without constriction or venom, thus they have strong jaws to overpower their prey



Plainbelly Watersnake - Nerodia erythrogaster


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Status

Plainbelly watersnake, Nerodia erythrogaster
Adult Plainbelly Watersnake, Louisa County, Iowa
 

ENDANGERED. It is illegal to kill or collect this species by law in Iowa. One of Iowa's rarest snakes, the copperbelly water snake may be found in swampy habitats in southeastern Iowa. Records are few for this snake and any reports would be appreciated. Please send reports to usThis e-mail address is being protected from spam bots, you need JavaScript enabled to view it or the Iowa DNR.

Description

Plainbelly watersnake, Nerodia erythrogaster, Iowa
Adult Plainbelly Watersnake, Louisa County, Iowa
 

Plainbelly water snakes are a medium sized Iowa snake. They range in length from 30 to 48 inches (Conant and Collins, 1998) and may be quite heavy bodied as adults. Adult plainbelly water snakes have a dark brown or black dorsum with no markings, even when wet. The belly is orange or red and is unmarked except for dark pigment that is sometimes present on the edges of the ventral scales. The labials also share the distinct coloration of the belly, and may also have dark suture lines.

Newborn plainbellies look much like northern water snakes and have a gray or very light brown ground color with striking black or dark brown bands and blotches. The crescents on the belly of the young usually have no red but are solid black or brown instead, and there may be a light pink wash on the belly. They change to the adult coloration quickly; specimens only one or two years old are marked like adults.

Plainbelly watersnake, Nerodia erythrogaster, venter, Iowa
Plainbelly Watersnake, venter, Louisa County, Iowa
 

Subspecies

I list the copperbelly water snake, Nerodia erythrogaster neglecta, as the subspecies found in Iowa (LeClere, 1998). Christiansen and Bailey (1991) and the State list the yellowbelly water snake, Nerodia erythrogaster flavigaster as the subspecies found in Iowa, however, there is much debate as to which one is found here. Please see the Subspecies Remarks found at the end of this account for more information.

Range

The plainbelly water snake is found in only a few scattered locations close to the Mississippi River in southeastern Iowa. This is one of Iowa's rarest snakes and any specimens seen in Iowa should be reported to us or the DNR. Ventral coloration is extremely important in the identification of this species and reports should include photos or a clear description of the belly. Incidental roadkills should be frozen until someone can pick them up. Remember, it is illegal to keep, harm, or kill these snakes in Iowa.

County distribution map for Plainbellywatersnakes in Iowa
County Records for Plainbelly Watersnakes in Iowa
 

Habitat

The plainbelly water snake may be found in the Mississippi river itself, or on one of the islands. Inland habitats consist of backwaters, pools in wet woodlands, rivers, ponds, sloughs, lakes, dams; any waterway closely associated with the Mississippi River.

Juvenile Plainbelly Watersnake, Nerodia erythrogaster, Iowa
Plainbelly Watersnake, Juvenile, Louisa County, Iowa
 

Habits

Plainbelly water snakes are similar to the other water snakes in habits. They are active from April to October and begin breeding soon after emergence. Many males may court one female at the same time. The females are usually quite a bit larger than the males. The pair usually will select a basking perch such as a shrub or branch overhanging water for copulation. Matings have been observed on the banks or even in the water, however. During breeding, both snakes may make undulating movements with their bodies and the pair may remain locked up for an hour or more.

Young are born alive in late June into August. They are roughly 6 - 10 inches at birth and are pugnacious like the adults. Minton (1972) reports litters of 8 to 37 from specimens from Indiana.

Nerodia erythrogaster, Plainbelly watersnake, copperbelly watersnake
Plainbelly Watersnake, Louisa County Iowa
 

Plainbelly water snakes are reported to wander farther distances from the waters edge than other water snake species. Specimens may be encountered in wet forests moving from pool to pool. They are most likely seen basking in shrubs, fallen trees, or vegetation over the water. They may also bask on the banks and use rocks, logs, or other debris for shelter. They seem to be more wary than northern water snakes and will slide into the water at any disturbance. They are also more likely to stay submerged after fleeing. They are mainly diurnal.

Juvenile Plainbelly Watersnake, venter, Louisa County, Iowa
Juvenile Plainbelly Watersnake, venter, Louisa County, Iowa
 

When caught, they will flatten their jaws and bodies. They release musk and strike viciously. Their bite will draw blood. Even after some time in captivity, they will still strike, although a very few may calm down. Plainbelly water snakes are nonvenomous!! The famous, and venomous, cottonmouth (or water moccasin), Agkistrodon piscivorus, is not found in Iowa. The farthest north cottonmouths have been recorded is central Missouri.

Food

Plainbelly Watersnake, venter, Louisa County, Iowa
Plainbelly Watersnake, venter, Louisa County, Iowa
 

Plainbelly water snakes are active hunters. They feed on a wide variety of animals associated with water. Amphibians seem to be the favored food, but fish, baby turtles, young snakes, worms, leeches, insects, crayfish, and mammals have also been reported as being consumed. A wider variety of prey is utilized at higher temperatures. They probably eat small meals every day or every other day and hunt by patrolling the water next to the shore for food. These snakes are not constrictors and simply swallow prey alive.

Subspecies Remarks

Juvenile Plainbelly Watersnake, Louisa County, Iowa
Juvenile Plainbelly Watersnake, Louisa County, Iowa
 

Although Christiansen and Bailey (1991) and the State of Iowa list the subspecies flavigaster as occurring in Iowa, Joe Monahan and I feel this is not entirely true. Clark(1903) first separated erythrogaster from sipedon as a distinct species. Conant (1943) described two new geographic races of erythrogaster which shed much light on populations found in the north and northeastern part of its range. Both workers separate these races by coloration. In fact, all references state only coloration as the definitive character in these races. Only a plain, bright yellow venter is diagnostic of the subspecies flavigaster (Dundee and Rossman 1985; Tennant 1997; Tennant 1985).

I have heard of only two reports of a water snake with a plain yellow belly seen in Iowa and no one has been able to provide evidence. The only water snake with a yellow belly that I have seen in Iowa was an aberrant northern water snake, N. sipedon, I found in Clayton County (well outside of recorded erythrogaster range) that had some gray dots that are not found on erythrogaster. Preserved specimens lose their color, and ventral coloration is an important key in identifying erythrogaster subspecies (Conant, 1943; Conant and Collins, 1991; Smith, 1961; Minton, 1972; Johnson, 1992; Holman et, al. 1993; Mount, 1975; Wright and Wright, 1957). Therefore, specimens must be described while alive and cannot be reliably identified from dated holdings.

Iowa material seems to fit the descriptions of the copperbelly water snake, N. e. neglecta, quite well thus far (Holman et. al. 1993; Minton, 1972; Smith, 1961) or at least as intergrades with this subspecies. Specimens found in the late 1970s had bright orange red bellies and labials (Christiansen, pers. comm.). There is recorded evidence of this in the photo here, which also appears in the Snakes of Iowa publication (Christiansen and Bailey, 1991), in that the labials are bright orange red, not yellow. The belly was the same color as the labials.

Joe Monahan found several specimens in 1993 in Muscatine and Louisa Counties that had bright orange red labials which can be seen in the photos. The belly was red with no trace of yellow on it. I found a roadkilled erythrogaster in Louisa County in 1996 about 18 inches in length. This snake, though badly mangled, definitely had no dorsal markings and was plain black above. The venter was orange red with black pigment along the edge of each ventral scale. This fits neglecta descriptions (Holman et. al. 1993; Minton, 1972; Smith, 1961). I have seen the flavigaster subspecies and this was not it. Smith (1961) records a neglecta from an island in the Mississippi River between Rock Island County, Illinois, and Muscatine County, Iowa.

If these snakes are found to be neglecta, this population may be eligible for protection under the Federal Endangered Species Act (Levell, 1997). Also, there exists the possibility that these snakes are intergrades between flavigaster and neglecta.

Smith (1961) mentions that most specimens found along the Mississippi River in extreme southwestern Illinois are such intergrades. There are no differences in scalation between the erythrogaster subspecies (Mount, 1975; Wright and Wright, 1957). Genetic work should be performed for additional clues, however, the live specimens needed for the Iowa sample size are extremely difficult to procure. If Iowa populations are intergrades, they are no more flavigaster than the other intergrading subspecies. The copperhead in Iowa is assigned a dual subspecies status and the same might be considered for this snake.

Again, this is one of Iowa's rarest snakes. Any sightings should be reported! A photo is very important. If possible, try to get a good belly photo as well. If this is not possible, at least try to get a good shot of the labials!

Northern Water Snake - Nerodia sipedon


Status

Northern Watersnake, Nerodia sipedon in Iowa
Northern Watersnake, Nerodia sipedon in Iowa
 

PROTECTED. It is illegal to kill or collect this species by law in Iowa. This is one of Iowa's most commonly seen snakes. They can be found in nearly every waterway and are usually seen while fishing.

Description

Northern water snakes are medium to large sized Iowa snakes. They range in length from 24 to 42 inches (Conant and Collins, 1998) and may be quite heavy bodied as adults. Northern water snakes are nonvenomous. There are so many pattern and color variations in certain populations, and in individual northern water snakes, that to list them all is not feasible for the length of this account!

Northern Watersnake, Nerodia sipedon in Iowa
Northern Watersnake, Nerodia sipedon in Iowa
 

Generally, they have light brown or reddish markings on a brown or grayish ground color. The markings consist of bands on the neck that become blotches on the back. There are smaller alternating spots on the sides and the ones closest to the ventral scales have a tendency to be red or reddish. The tail is ringed and the rings are the same color as the dorsal markings. The belly is white with brown or red half-moon shaped markings. These markings are sparse or absent anteriorly and become much more numerous posteriorly. Sometimes there is a yellow, orange, or pink stripe running longitudinally down the center of the vent. The crescent shaped markings may still be present with this stripe, but if they are not, there may be very small gray or brown dots scattered randomly about the belly.

Northern Watersnake, Nerodia sipedon in Iowa
Northern Watersnake, Nerodia sipedon in Iowa
 

Larger adults may be a solid brown or black when they are dry. Newborn northern water snakes have a gray or very light brown ground color with striking black or dark brown bands and blotches. The crescents on the belly usually have no red but are solid black or brown instead. Subadults are quite reddish in overall appearance.

Subspecies

Nerodia sipedon has three subspecies; only the northern water snake, N. s. sipedon, occurs in Iowa.

Range

The northern water snake is found statewide in Iowa except in the northwest.

County records for the Northern Watersnake in Iowa
County records for the Northern Watersnake in Iowa
 

Habitat

The very common northern water snake is, as its name implies, a snake of the water. Ponds, marshes, streams, river backwaters, and lakes provide the preferred habitat for this serpent. Thick vegetation along the banks with small shrubs and trees afford basking opportunities that are important for this species. It adapts rather well to moderate human interference. City parks with water and even heavy traffic fishing spots may have good populations of northern water snakes.

Ventral surface of the Northern Watersnake
Northern Watersnake, ventral
 

Habits

Northern water snakes are by far the most abundant of the three water snake species in Iowa, and also one of the most common large snakes in general. It is often seen by fishermen, who may mistake them for the venomous cottonmouth, which is not found in Iowa. This snake is diurnal, even during hot weather. It may be observed basking upon branches, shrubs, tree roots, and along the banks of waterways, often in large numbers on a favorite basking spot. Young and newborn water snakes may be found hiding beneath logs or flat rocks close to water. They are wary and will slip off their basking perch at any sign of danger. Some may swim with their heads above water to the other side of the bank or swim back to the shore in a semi-circle. Others will dive to the bottom and anchor themselves to logs, branches, rocks, or other debris. Most will resurface within five minutes, but they are capable of remaining submerged for an hour and a half (Ferguson and Thornton, 1984)!

Northern water snake, Nerodia sipedon, ventral
Northern Watersnake, ventral surface
 

If cornered, they will flatten their jaws and bodies making themselves look like ribbons! They will strike and bite viciously and repeatedly. If picked up, they will release musk and fecal matter, and in very nervous specimens, regurgitating any recently eaten meal. Even after being held for some time, they will not miss an opportunity to bite, and their saliva contains anticoagulant properties that make the lacerations bleed profusely. The treatment, however, is only soap and water. These are nonvenomous snakes!! The famous, and venomous, cottonmouth (or water moccasin), Agkistrodon piscivorus, is not found in Iowa. The farthest north cottonmouths have been recorded is central Missouri.

Watersnake, ventral surface
Northern water snake, ventral surface
 

Northern water snakes are active from April to October, spending their winters in rock crevices they have migrated to from the water. I found a neonate northern water snake in Clayton County on Sepetember 29. It was found under a rock at the base of a rocky bluff about 60 meters upland from a trout stream. There are often other species of snakes hibernating with them. Neonates of this species will often hibernate communally and in relatively large numbers when compared to the adults. Some may hibernate near their summer sites if suitable dens such as burrows, large rocks, bridges, or dams exist. They emerge in spring and migrate back to their summer sites close to water. This is where copulation takes place. I have seen two pairs of northern water snakes copulating in Louisa County on May 2. Many males may court one female at the same time. The females are usually quite a bit larger than the males. The pair usually will select a basking perch such as a shrub or branch overhanging water for copulation. Matings have been observed on the banks or even in the water, however.

Northern watersnake, Nerodia sipedon
Northern Water Snake, ventral surface
 

During breeding, both snakes may make undulating movements with their bodies and the pair may remain "locked up" for an hour or more. Young are born alive in late June into August. They are roughly 6 - 10 inches at birth and are pugnacious like the adults. Five to sixty young may be produced in a single litter or a couple litters a few days apart and there is a fantastic account of 99 young born in a litter to one female! A large female from Linn County gave birth to fifteen young in July.

Food

Watersnake, lateral banding
Northern Water Snake, lateral pattern
 

Northern water snakes are active hunters and may hunt both day and night. They feed on a wide variety of animals associated with water. Fish, amphibians, baby turtles, young snakes, worms, leeches, crayfish, and mammals are consumed. A wider variety of prey is utilized at higher temperatures. They eat small meals every day or every other day and hunt by patrolling the water next to the shore for food. They sometimes swim through a school of small fish with their mouths wide open and swallow anything they can catch or herd fish into a shallow area of water and then create a barrier with a loose coil of their bodies. On a summer night in Louisa County, I was attempting to rescue small turtles and frogs from a dam that had been partially closed. The current was very strong and created a whirlpool near the door of the dam. These animals were trapped on debris that was constantly shifting, but they could not swim out. It was just after dark and a large northern water snake suddenly appeared in my flashlight beam. The snake swam right in and immediatly began feeding on the frogs that were trapped. It ate a few, and then suddenly, and quite effortlessly, swam out and dissappeared. These snakes are not constrictors and simply swallow prey alive.


Typical half moon ventral pattern of Northern Water Snakes
Nothern Water Snake, ventral
Massasauga Rattlesnake - Sistrurus catenatus


Status

Massasauga rattlesnake, Sistrurus catenatus
Massasauga rattlesnake, Wisconsin specimen
 

ENDANGERED. It is illegal to kill or collect this species by law in Iowa. Reports are needed for parts of western, southern, and eastern Iowa. Please report any sightings to us or the DNR.

Description

This is a small rattlesnake that measures 17 - 39 1/2 inches in length (Conant and Collins, 1991). It is VENOMOUS! There is a row of black or dark brown middorsal blotches on a lighter brown or gray background. There are two or three rows of small spots on the sides. All blotches and spots may be outlined in white. The blotches usually turn into rings on the tail. There are usually five rings that are 3 - 3 1/2 scales wide and 11/2 scales apart. There is a rather broad dark stripe from the eye past the angle of the jaw. The belly is mostly black with irregular white or yellowish marks. Melanistic specimens are known; these specimens are uniformly black dorsally and ventrally. There are usually some light markings on the chin and throat that remain, however.

Massasauga rattlesnake, Sistrurus catenatus, Scott County, Iowa
Massasauga rattlesnake, Scott County, Iowa
 

Massasaugas are stout bodied snakes with a triangular shaped head. The pupils are vertically elliptical and there is a heat sensitive pit located between the eye and nostril. This pit is larger and positioned lower on the face than the nostril. There is a rattle at the end of the tail. The rattle is comprised of a series of interlocking keratinous segments that make a buzzing noise when the tail is vibrated. The scales are keeled and the anal plate is single.

This snake may be quite difficult to distinguish from the harmless fox and water snakes. One may look for a rattle at the end of the tail, but massasaugas usually have small, dark rattles that are not always distinctive. Massasaugas will rattle with their tails off the ground (though not as high as other rattlesnake species). Harmless snakes that vibrate their tails must hold their tails close to the ground to produce noise. The best thing to do is leave it be if you are unsure of what species it is.

Close-up, Massasuaga rattlesnake
Close-up, Massasuaga rattlesnake, Wisconsin specimen
 

Subspecies

Two subspecies, the eastern massasauga, Sistrurus catenatus catenatus, and the western massasauga, S. c. tergeminus are believed to occur in Iowa. The eastern subspecies indisputably occurs in very few, small marshy areas in eastern Iowa. A small population in southwestern Iowa shows characteristics of the western form.

Range

Massasaugas are extremely rare in Iowa. There were larger populations in eastern Iowa, and throughout southern Iowa. Today, these populations are reduced to less than a half dozen scattered about eastern and southeastern Iowa, and in southwestern Iowa.

County Records for the Massasuaga rattlesnake in Iowa
County Records for the Massasuaga rattlesnake in Iowa
 

If you see a massasauga in Iowa, do not kill or harm it in any way. Also, do not attempt to catch or move it. It may be a useful record, however. If you wish to report it, try to take a good picture of it. If the specimen is found dead, the specimen will be useful. Be advised that reflex actions, which may occur even hours after death, could result in a fatal bite. They are also an endangered species in Iowa and the specimen must be turned over as soon as possible. A good photo of a dead snake will suffice! Most importantly, give clear and exact locality documentation, and report it to the DNR, or us!

Habitat

Massasauga rattlesnake, Sistrurus catenatus
Massasauga rattlesnake, Wisconsin specimen
 

Most authors seem to agree that massasaugas prefer low, swampy areas close to marshes, lakes, and rivers. This is the habitat in which I find them in Iowa. They seem to elevate themselves from the borders of such habitations, but do not wander a great distance from a particular body of water, except perhaps in summer, when a few specimens may be found in open grasslands, meadows, or dry woodlands, even farms. The majority prefer to sit in tufts of grass or under rocks a short distance from the water. Bailey (1944) found specimens well away from water when they had a more expansive range in the state.

Habits

Some references state that massasaugas are slow, sluggish snakes that are quite passive and slow to rattle or strike. They rely on their coloration for camouflage to avoid detection. One may almost step on this snake before provoking a reaction from it. I have found that they are diverse in their behavior as some will rattle at the least provocation and strike repeatedly. One specimen, however was found after a friend had stepped right over it. It did not rattle until afterward when I tossed a cover board on it! The massasauga's rattle is small, and sometimes can only be heard at relatively close distances.

Massasauga rattlesnake, venter, Scott County, Iowa
Massasauga rattlesnake, venter, Scott County, Iowa
 

This snake is generally diurnal except during extremely hot weather. They seem to enjoy warm overcast weather as this is the condition under which many specimens were found. Mornings are a good time to look for basking massasaugas. They take shelter under rocks, logs, pieces of bark, under piles of brush, muskrat houses, or in crayfish burrows.

They breed in the spring and sometimes again in the fall. They may only breed every other year or less and are sexually mature at the age of three or four. They give birth to living young (ovoviviparous). The young number from 5 - 24 and are about 5 - 7 inches in length. The young are equipped with fangs and are venomous as soon as they are born. They are usually brighter colored than the adults. Instead of hibernating communally, like many species of snakes, they hibernate alone in mammal, or, more commonly, crayfish burrows, crevices or rock piles close the water, and other areas where they can gauge the water line. It is reported that they emerge with the spring flooding and basically follow the water line during this time.

Massasauga rattlesnake, Scott County, Iowa
Massasauga rattlesnake, juvenile, Scott County, Iowa


Lined Snake - Tropidoclonion lineatum


Status

Lined Snake, juvenile, Minnesota specimen
Lined Snake, juvenile, Minnesota specimen
 

PROTECTED. It is illegal to kill or collect this species by law in Iowa. Lined snakes are secretive and not commonly seen. We would welcome any reports of lined snakes to help us fill in the gaps of its presently spotty distribution.

Description

This snake resembles a small, colorless garter snake. It is 8-10 inches long and is non venomous. There is little variation in this species so identification is easy. There is a light (almost always white; rarely yellow) mid dorsal stripe. There is also a light lateral stripe on each side of the snake. Ground color is gray or brown and there are some dark dots between the dorsal and lateral stripes. The belly is plain white with two rows of bold, black half moons down the center. Sometimes there is a yellowish stripe over the moons, but they still retain their boldness. This characteristic is enough to distinguish it from all our other snakes. The scales are keeled and the anal plate is single. No other Iowa snake has a double row of black half moons down the belly.

Lined Snake, DOR, venter, Cherokee County, Iowa
Lined Snake, DOR, venter, Cherokee County, Iowa
 

Subspecies

No subspecies of Tropidoclonion lineatum are recognized any longer.

Range

The lined snake is found in scattered populations in northwestern and throughout southern Iowa. Although not under any special protection in Iowa, we would like to hear of reports of this snake.

Distribution Map for the Lined Snake in Iowa
County Records for the Lined Snake in Iowa
 

Habitat

Lined snakes are found in prairies, grasslands, pastures, woodland edges, and even city parks, city lots, cemeteries, and backyards.

Habits

Lined snakes are secretive snakes hiding beneath debris during the day. They often hunt at night above ground when earthworms are present and easily captured. This snake is inoffensive and if it were to bite, it could do no damage at all. It breeds in the fall; this is why most specimens are found (by far!) during this time in Minnesota and Iowa. I have seen many roadkilled specimens in Cherokee County in October moving to their hibernaculums. In other states, they may also be quite common in the spring, however. The female gives birth to 5-10 young in autumn. They are three inches long at birth. Lined snakes hibernate deep in the rocky outcroppings.

Food

Lined Snakes favorite food is earthworms, but slugs, snails, soft-bodied insects are also consumed.


 

Food

The diet of the massasauga is comprised largely of small mammals, but small birds, lizards, frogs, toads, and other snakes are also consumed. While adults usually feed upon mice, small snakes are an important food item for young massasaugas. It is interesting to note that this snake will bite and release adult mice then search them out and swallow them after they are dead. When birds and lizards are to be consumed, they are held in the snake's jaws until the venom takes effect.

Fox Snake - Elaphe vulpina


 



Status

PROTECTED. It is illegal to kill or collect this species by law in Iowa. Common throughout all of Iowa, they are protected under state law.

Description

Measuring 36 to 56 inches in length, this is one of Iowas larger non venomous species of snake (Conant and Collins, 1991). Ground color ranges from straw yellow to dark brown. Occasionally, there may be orange, yellow, or reddish pigment between the scales. There are large distinct body blotches that are very dark brown or black. These blotches become rings on the tail. The head may be light brown with yellow, orange, or reddish highlights and is usually unmarked except for a small design on top. The belly is a dirty yellow with black checkering.

Fox Snake, Elaphe vulpina 

Young fox snakes are noticeably lighter than adults, having a light brown or gray ground color and lighter body blotches with black outlining. The head is usually boldly marked with black lines, the most conspicuous of these being the line that travels diagonally from the eye to the angle of the jaw and the line on top of the head connecting the eyes. As with all North American rat snakes, the scales are weakly keeled (poorly defined keels on the dorsal scales and smooth lateral scales) and the anal plate is divided.

Subspecies

There are two subspecies of fox snakes (Conant and Collins, 1998). The western fox snake, Elaphe vulpina ulpina, is the only subspecies found in Iowa. Collins (1997) listed the subspecies as two seperate species.

Image

Range

The fox snake is the most common constricting snake in most parts of Iowa and occurs throughout the state. A number of south central counties appear to have lower numbers of fox snakes as perhaps the more diverse feeding habits of prairie kingsnakes may outcompete fox snakes.

Habitat

This snake occupies more moist habitats than other large Iowa snakes. Woodland and woodland edges, prairies, lowland meadows, and rocky outcroppings near rivers provide food, shelter, and overwintering sites for fox snakes. They are especially common in river and stream valleys. Fox snakes adapt more readily to human habitations and habitat disturbance. Often, they are found well within the city limits of even the largest Iowa cities. Ironically, some city ordinances may ban the keeping of constricting snakes under their dangerous animal law, even though the fox snake, a constrictor, is found there naturally!

County Range Map for the Fox Snake in Iowa
County Records for the Fox Snake in Iowa
 

Habits

Fox snakes are very active during the day, especially in the spring, but often again in the fall as well. During the hot summer months, fox snakes choose to move about at night, just like many other Iowa snake species. When encountered, fox snakes are usually very passive opting to flee even when cornered. When handled, they usually do not strike or bite, but they may release a mild musk from their scent glands at the base of the tail. The musk smells like that of a red fox, hence the common name (Vogt, 1981). More excitable specimens, especially juveniles, will coil and strike with a short, forced hiss (LeClere, 1996). They will also vibrate their tails producing a rattling or buzzing sound. This behavior often causes them to be misidentified as rattlesnakes, bullsnakes, and, because of their copper-colored head, copperheads. They are often killed because of this.

Fox Snake from owa 

Bullsnakes (which are harmless) have a much more pointed snout than fox snakes and a single anal plate. Iowas timber rattlesnakes have thin, black bands (not spots) across the body and have a rattle at the end of their solid black tails. Fox snakes, however, have large, dark spots on the body, no rattle, and the tail is not solid black. Copperheads have a very restricted range in Iowa, and copperheads are much more orange in overall coloration without any dark brown or black spots.

Close up of a Fox Snake

Fox snakes emerge from hibernation in April and are active until October. They hibernate in rocky crevices or man-made structures that extend below the frostline (Jessen, 1993). They mate in spring. Females are oviparous and lay about 10 - 20 eggs. The young hatch in August and are about 8 - 12 inches in length. A female fox snake from Johnson County laid 12 eggs on 3 July. The eggs ranged from 37 to 46 mm. The eggs hatched on 12 August; an incubation period of 40 days at approximately 80 degrees F. The young measured from 273 to 342 mm total length at hatching. Another female fox snake from Louisa County laid 8 eggs on 5 July. The eggs averaged 42 mm. The eggs hatched 16 August; an incubation period of 42 days at about 80 degrees F. The young measured from 282 to 344 mm total length at hatching.

Fox Snake close up 

These snakes spend most summer days beneath debris that retains the suns warmth. They are strong snakes and can climb with ease. However, most prefer to travel along the ground. They also swim well and make use of this ability. Many fox snakes have been found crossing rivers or well away from the shores of ponds or lakes (Breckenridge, 1944). Fox snakes may travel a great deal during the active part of their season. Many of these snakes are hit by automobiles as a result of their frequent road crossings and because they may bask on the road for warmth (Breckenridge, 1944, Oldfield and Moriarty, 1994, Jessen and LeClere, personal observation). Males are often hit in the spring, and females are often hit during egg laying season as they search for suitable sites to lay their eggs. In the fall, neonates traveling to their hibernaculums are most often hit by automobiles (Blasus and LeClere, pers. obs.).

Photo of a Fox Snake in Iowa 

Food

Fox snakes are valuable consumers of rodents, which make up the bulk of their diet. This snake belongs to the rat snake group and is a powerful constrictor. Young fox snakes may feed on frogs or young mice (Oldfield and Moriarty, 1994). Adults have been known to eat birds and their eggs (Vogt, 1981). I found a large female crossing the road in LeSuer County, MN at dusk with bird feathers hanging from the corners of her mouth and a large lump in her stomach.

Fox Snake in Iowa


Juvenile Fox Snake












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Milk Snake - Lampropeltis triangulum

 

Status

PROTECTED. It is illegal to kill or collect this species by law in Iowa. Milk snakes are common, but since they are very secretive, they are seldom seen.

Eastern Milksnake, milk snake, Linn County, Iowa

Description

The milk snake is a medium sized Iowa snake that is 24 to 52 inches in length, but quite often maintains a slender build. It is nonvenomous. Although this snake's blotched pattern remains consistent, its general coloration is quite variable. Some specimens can be beautifully light colored, having a light gray or brown ground color and bright to rusty red body blotches. Others can look a lot like fox snakes having an overall brown coloration. Still, others can be a dark gray with little or no difference in color between the ground color and blotches, only the black borders (which are always present) indicate the presence of blotches.

 

Milksnake, intergrade, Woodbury County, Iowa

There is an alternating row (sometimes two) of lateral spots on the sides. These vary in size, but are never as big as the dorsal blotches. The belly is white with clusters of black checkers scattered randomly about the venter. Often there is a pink or peach wash to the general ventral coloration. There is a light V or Y marking at the back of the head, but this is sometimes replaced by a light spot. The snout is usually white. The scales are smooth and the anal plate is single.

Subspecies

Two subspecies of milk snake are found in Iowa, the red milk snake, L. t. syspila, and the eastern milk snake, L. t. triangulum. The red milk snake is usually brightly marked. It differs from the eastern milk snake in distribution and that it has a light ground color with bright red blotches. These blotches are large and extend down on the sides almost to the ventral scales. This results in the reduction in the size and number of the lateral spots.

Red Milksnake, Decatur County, Iowa

The eastern milk snake was basically described in the description section. It is much more drab in coloration than the red milk snake and has smaller dorsal blotches which make the lateral spots larger and more numerous. These subspecies meet and intergrade heavily in eastern Iowa and surrounding areas. Intergrade specimens share characteristics of both subspecies.

A few specimens from northwestern Iowa appear to have genetic influence from the western forms of L. triangulum (most likely L. t. multistriata). These intergrade snakes have a large amount of black on top of the head, a gray ground color, and orangish dorsal blotches. An example is the photograph showing the intergrade from Woodbury County (above). I would be interested in pictures from milk snakes from this area. A larger sample size is needed to determine the extent of these intergrades in northwestern Iowa.

County Range Map for the Milksnake in Iowa

Range

Milk snakes are found statewide in Iowa. The most pure eastern milk snakes can be found in northeastern Iowa, and the most pure red milks are found in the western half of Iowa. The others are intergrades between the two subspecies.

Habitat

Rocky hillsides provide the favored habitat in Iowa, at least that is where they are most often seen. Farmlands, grasslands bordering woodlands, and rock outcroppings, especially near waterways, are used. Milk snakes are also found in woodlands and in the loess hills, but here they are rarely discovered unless they are found hit on the road or crossing a trail.

Habits

Milk snakes are diurnal in the spring and fall becoming largely nocturnal in summer. They are very secretive and are rarely found in the open. They spend much of their time hiding beneath logs, rocks, boards, bark, and other debris. Only on a few occasions have I observed milk snakes sunning in the open. Occasionally, they may climb in search of food or to escape severe flooding. My cousin found a red milk (nice large, bright, red blotches with yellow interspaces) in Johnson County swimming into shore during a flood. There were many trees about 20 meters away from shore. This was undoubtably where the snake came from.

Red Milksnake, Madison County, Iowa

Milk snakes endure many temperature extremes hiding under tin or rocks in hot weather when other species of snakes are underground, or hiding beneath rocks or boards with water or mud under them. Wild caught milk snakes can look extremely worn having many scars, skin lesions, (especially before a shed) or stub tails.

This snake is active from April to September. Most milk snakes move away from their rocky outcropping or mammal burrow hibernaculums to farms and grasslands with suitable food and cover during the summer. A few remain near their overwintering spots, however.

Mating takes place in spring or early summer. The female lays about 10 eggs in an area selected for its high humidity and warmth. Incubation lasts from 28 to 39 days. In the fall, the young milk snakes hatch from their eggs. They are 5 to 10 inches at hatching and have the most spectacular coloration they will ever have. They are bright white or gray with rich pure red blotches. Milk snakes are usually apt to coil, strike and bite when captured, especially during cold weather. They strike with a short, forced hiss and try to quickly slither away and under cover when they get the chance. Even after they are picked up, they may casually turn and chew on fingers or the arm of the person holding it. They also vibrate their tails and release musk.

Food

Milk snakes feed on a wide variety of animals including mice, reptiles, amphibians, invertebrates, reptile eggs, birds and birds eggs. They are a type of kingsnake and will consume venomous snakes when they chance upon them. They are at least partially immune to the venom of the venomous snakes in their range and many venomous serpents will use defensive tactics other than biting to protect themselves from kingsnakes. Young snakes comprise a large portion of a baby milk snakes diet, but they are not found to be the most significant food item for adults (Breckenridge, 1944). Adults consume mainly rodents. Milk snakes are constrictors and kill their food by suffocation. Milk snakes are so named because it was once believed that these snakes would enter barns and steal milk from cows. This is false; snakes only drink water. They would become sick if they were to drink cows milk. Snakes also have sharp teeth; no cow would stand still for that! The milk snakes were in the barns actually helping the farmers by looking for rodents to eat.


Eastern Hognose Snake - Heterodon platyrhinos



Status

Hognose snake, Heterodon platyrhinos
Eastern Hognose Snake in Iowa
 

PROTECTED. It is illegal to kill or collect this species by law in Iowa. Although eastern hognose snakes are widely distributed in Iowa, they are relatively uncommon in most parts of the state.

Description

This is a medium to large Iowa snake that may be 24 to 46 inches long and has a very stout body. It is not considered venomous. They are rather variable in pattern and color; two phases may be found: spotted and solid. Spotted specimens have a brown or yellow ground color with darker brown or black blotches. These alternate with smaller dark spots on the sides. The blotches may turn into rings on the tail. There may be red or orange pigment in the skin between the scales, and this pigment may occasionally infringe upon the scales themselves. In some populations, adults are a solid color that may or may not have remnants of blotches. The ground color on solid individuals may be black, gray, or olive. Olive is the most common solid color phase in Iowa.

Heterodon platyrhinos, Eastern Hognose Snake
Hognose snake, Heterodon platyrhinos
 

The labials are light colored on all the variations. Regardless of dorsal coloration or pattern, the belly is yellow, gray, or pinkish, sometimes with gray or greenish mottling. The underside of the tail is always lighter colored than the belly. Eastern hognose snakes always have a dark longitudinal blotch behind each eye extending some distance onto the neck. These blotches are black in eastern hogs, not brown as in its cousin, the western hognose. The western hognose also has a light anal plate and the underside of the tail is black; the same color as the belly. The eastern hognose snakes underside of the tail is lighter than the belly. The rostral scale is enlarged, pointed, and keeled, just as in the western hognose, but it is not as upturned. The scales are keeled, and the anal plate is divided.

Subspecies

There are no recognized subspecies of the eastern hognose snake, Heterodon platyrhinos.

Range

In Iowa, eastern hognose snakes are found statewide, except for the north central region.

 

County Records for the Eastern Hognose Snake in Iowa
County Records for the Eastern Hognose Snake in Iowa

Habitat

Eastern hognose snakes are not as choosy about their habitats as their western cousins. Heavily wooded areas, prairies, and grasslands are common habitats. They are even found on bluff prairies on occasion. Like western hognose snakes, however, these snakes prefer sandy or loamy soil in which to burrow. Eastern hognose snakes can be found with western hognoses where their ranges overlap in Iowa (Berberich, Dodge, and Folk, 1971; Christiansen, 1983). Easterns also adapt to many other habitat types than westerns and therefore are more widespread and common in Iowa. Eastern hognose snakes are found in more damp situations as they feed heavily upon amphibians. They are also found under flippable cover (as that afforded by rocky hillsides or logs) more often than the western hognose, although still rarely.

Eastern Hognose Snake, Heterodon platyrhinos
Eastern Hognose Snake, Heterodon platyrhinos
 

Habits

Heterodon platyrhinos will fan its head and neck much like a cobra when alarmed. Loud and prolonged hissing is accompanied by short jabs with the head as often away from the attacker as toward it. The snake will not open its mouth to bite, and hognose snake bites originating from defense are rare. Even a large 43 inch specimen I found in Johnson County would not bite, but it acted as though it would.

If the attacker continues to press upon the hognose, it will open its mouth, writhe as if in pain and finally roll onto its back with its mouth open and tongue hanging out. It cannot be induced to move. Because the snake keeps its mouth open during the entire death scene, lining at the back of the mouth closes off the opening to the esophagus to prevent the swallowing of dirt. This is also aided by an increase in saliva production, which may run out of the mouth (readily seen when the snake is picked up), taking much of the dirt with it. If it is righted, it immediately rolls onto its back again. Not until the snake feels safe will it right itself and continue on with its normal activities. Eastern hognose snakes are more elaborate with their act than the western hognose, and even though they will perform the act in captivity for a longer period of time, they soon quit acting in captivity.

Eastern Hognose Snake, Heterodon platyrhinos playing dead
Eastern Hognose Snake playing dead

Eastern hognose snakes are diurnal and actively hunt for food. They may be observed basking in early morning and again at dusk. They are one of the few snakes that dig their own burrows, although they do not live in them for prolonged periods of time. Logs, rocks, boards, and other cover are used-especially just before shedding.

These snakes breed in the spring. They are oviparous and lay 10 - 30 eggs in a sandy area. The eggs hatch in about two months and the young are 5 - 12 inches at hatching. They are much brighter colored than the adults. H. platyrhinos hibernate from October to late April in mammal or self constructed burrows.

Eastern Hognose Snake, Heterodon platyrhinos
Eastern Hognose Snake, Heterodon platyrhinos

Food

Eastern hognose snakes consume amphibians, mainly toads, and use their snout to dig them up as toads spend much time in self made burrows. They also consume small mammals, birds, birds eggs (ground nesters), insects, lizards, snakes, reptile eggs, and carrion. They are immune to the toxic secretions that toads produce via the partoid glands.Eastern hognose snakes are not constrictors and swallow their prey alive.

Hognose snakes are opisthoglyphous (having fangs at the back of the mouth) and they use this feature to deflate toads which may puff themselves up with air to unswallowable proportions. I mentioned previously these snakes were nonvenomous, but there is some evidence that they may be mildly venomous (LeClere, 1996). Although there have been many cases of Heterodon envenomation, its toxicity is controversial. McAlister (1963) took extract from the salivary glands of H. platyrhinos and injected white mice, spring peepers, Pseudacris crucifer, Fowlers toads, Bufo woodhousei fowleri, and chorus frogs, Pseudacris triseriata, in the thighs. The mice were unaffected.

Eastern Hognose Snake, Heterodon platyrhinos
Eastern Hognose Snake, Heterodon platyrhinos

Fifteen of the seventeen amphibians died within two days. Subcutaneous hemorrhage, edema, and inflammation led McAlister to conclude that the venom is hemotoxic. Other authors have concurred that this genera of snakes is venomous; others discount it. Anderson tried several times to induce a H. platyrhinos to envenomate him. He even made an extract and administered it to himself. It produced nothing more than slight burning.

 

More studies must be done to give a more concrete answer. Even so, it may be concluded that individual sensitivity plays the most important role in producing a malevolent affect. Bacteria cannot be discounted in these cases. With as many people that have had toxic symptoms from hognose snakes, there are many who have not. I have had a H. nasicus chew and embed one fang into my thumb without producing any ill effects, but I have a friend that did get a reaction from one. I have also experienced some of the swelling and itching described for some of the Heterodon accounts, to a lesser degree, from a yellow rat snake, Elaphe obsoleta quadrivittata, and got a bad reaction from a bite from a Madagascar giant hognose snake, Leioheterodon modestus. This could possibly be individual sensitivity to a particular saliva. A study conducted on a greater number of humans and different species of amphibians, reptiles, and mammals may provide better answers.


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