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Snakes: Facts

Snake Basics

Green Snake

Snakes are vertebrates — that means they have a skeleton, which in the case of snakes is mostly a skull and lots and lots of rib bones.

They do not have ears as most of us think of an ear. They do have a sensory ear bone, called the columella, which detects vibrations.

Snakes use their tongues to detect smells to find food or stay away from enemies. Their eyes do not move inside their head, and they do not have common eyelids.

Some types of snakes have a special pit located near their eyes that allows them to detect small changes in temperature. This allows them to be aware of the heat given off by the bodies of rodents or other animals they might want to eat.

A snake's skin is made of a variety of sizes of scales. The scales near the head are small while the scales on the underside of their body are thick and protect their bodies from the ground.

Snake Scales
A snake continues to grow throughout its life. They periodically shed their skin as part of this growing process.

Snakes live on every continent of the world except Antarctica. There are even species which swim in the ocean.

How Snakes Eat

Snakes are carnivorous. That means that they eat other animals. Snakes do not have the right kind of teeth to chew their food so they must eat their catch whole. Their jaw is structured in such a way that it allows the mouth to open wider than their own body in order to swallow their prey whole.

Snake Eating

Once swallowed, the muscles of their body and their hook-shaped teeth help push the food toward the stomach. The food is then digested over a long period of time — depending upon how warm the snake is. The warmer their bodies, the faster they digest their food. But it generally takes 3–5 days for food to be digested. Very large snakes such as the anaconda from South America eat rather large prey, so their digestion can take weeks.

Poisonous or venomous snakes inject poison or venom into their prey. This starts the digestive process even before the snake swallows that food.

Snakes tend to eat rats, birds and their eggs, mice, chipmunks, frogs, gophers, and other small rodents. Some species will even consume insects or earthworms. Very large snakes will even eat deer, pigs, monkeys and other large prey. The Kingsnake is known for the fact that it will eat other snakes, including venomous snakes like rattlesnakes.

Snakes Are Cold Blooded

Sick Snake

People, other mammals and birds are known as a warm blooded animals. Our bodies can regulate the temperature up or down as needed for our environment. We sweat when we are hot and shiver when we are cold.

Amphibians and reptiles are cold blooded. Their body temperatures match that of their surroundings. Because of this, cold blooded animals can not survive well in extreme hot or cold. To warm themselves they will move to a sunny rock or roadside. To cool their bodies they will seek shade or sometimes even dig a hole in the ground.

How Snakes Move

Side Winder

The bodies of snakes have no feet, flippers or legs to propel them along. They must use the action of their scales and muscles to scoot their bodies across the ground. The scales on the underside of their bodies are specialized for this purpose like the tread on a tire.

Different species of snakes use one of the four manners of movement: concertina, serpentine, sidewinding, and caterpillar. Visit HowStuffWorks to see how these four styles of movement propel a snake.

Snakes That Fly?

Ok, so not like a bird — with wings — but some snakes do hang from branches and swing themselves into the air. Then by flattening their ribcage and making a side to side motion, they keep their bodies in the air long enough to glide for about 109 yards before crashing to the ground or into another tree.

The five different flying snakes are all poisonous and live in the tropical rainforests of Sri Lanka and Southeast Asia. No snakes can fly upwards or take off from the ground.

Snakes Can Swim

Swimming Snake

Many species of snakes can move about the water. Some just slide on the surface, while others can actually swim underwater. A few species even live the majority of their lives in the ocean — these are known as sea snakes. They do come to the surface to breathe air, but can often stay down for upwards of an hour. Sea snakes dine on fish and eels.

Snake Teeth


The type of teeth a snake has is dependent upon how the species catches food.

All non-poisonous snakes have teeth on the upper jaw and the lower jaw. A snake can often grow more teeth as needed because teeth are sometimes lost while feeding. The teeth are hook-shaped and angle toward the throat.

Poisonous snakes have either grooved or hollow fangs. The poison, which comes from glands located under each eye, flows down the groove or through the hollow portion of the fangs and is injected into the prey.

Snake Babies


Female snakes produce young about twice per year. In some species babies are born alive. Other species lay eggs. In a strange combination of the two, some snakes have eggs that stay in their bodies until the eggs hatch and then the babies are born. Snakes can have anywhere from one to 150 baby snakes at a time.

Snake eggs are not hard like a chicken egg, but are leather-like and can be torn open by the baby snake from the inside with a special “egg tooth” that the snake will lose soon after hatching.

Snakes do not take care of their offspring, but a few species will protect the eggs and then the new babies for a very short time after they have hatched. Baby snakes are then left to fend for themselves.



Some snakes have a camouflage coloring which hides them from predators. Blending into the surroundings also keeps their potential prey from spotting them.


Coral Snake

Some snakes have coloring which mimics another snake for the purpose of confusing predators. For example, the poisonous Coral snake looks similar to the non-poisonous Scarlet Kingsnake. Both snakes live in North America.


Snakes that live in cold climates plan ahead for the winter by eating extra food so that they can hibernate during the coldest season. Their bodies are not really asleep, but in a special condition that makes them appear as if they are dead to people who are not aware.

Idaho Snakes

Idaho is home to a number of snakes, both poisonous and nonpoisonous. There are 11 common species of snake found in the state:

  • Rubber Boa
  • Racer
  • Ringneck Snake
  • Night Snake
  • Striped Whipsnake
  • Gopher Snake
  • Longnose Snake
  • Ground Snake
  • Common Garter Snake
  • Western Terrestrial Garter

Visit the web site at Idaho State University to learn more about each of the above species along with other reptiles of Idaho. Look for the Reptiles of Idaho Checklist.

Poisonous Snakes in the United States

There are 116 species of snakes in the United States. Only 19 of these species are poisonous. The bite of these creatures can be very dangerous. A person who is bitten by one of these should seek medical attention quickly. Only the rattlesnake is typically found in Idaho. Here are the poisonous snake species found in the U.S.


  • Copperhead
  • Cottonmouth water moccasin
  • 2 kinds of coral snakes
  • 15 kinds of rattlesnakes

The Western Rattlesnake


The Western Diamondback Rattlesnake is one of the most feared snakes in North America. There are a number of different rattlesnake species in North and South America. Their coloring is distinctive and they are well known for the diamond-shaped design along their back. They can grow to be from 3 to even more than 5 feet long. They live in a variety of environments including forests, deserts and grasslands. They prefer to be in rocky areas where they can warm themselves against the heat of the rocks or cool themselves in the shade between the rocks.

Rattlesnakes are pit vipers. That means that they have a special pit between their eyes that senses temperature — useful for hunting prey. Their diet is mostly small rodents, but they will also dine on frogs, fish and other small creatures. They are very poisonous, so it is wise to stay away should you ever come across one.

The best thing you can do is stay away from rocks and to keep your ears tuned to the noise of a rattling sound. And be aware!! Baby rattlesnakes can not rattle until they have shed their skin at least once. A baby rattler is also likely to inject more venom when they bite than an adult will, making a baby rattlesnake's bite more dangerous.

Exotic Snakes


The cobra is well known for its hood that it puffs out when in a defensive stance. They are the world's longest venomous snake and are found in the Philippine islands, southern Asia and Africa. The cobra's bite is deadly, but some species of cobra also spit venom at their victim. Snake charmers use cobras for their demonstrations because the cobra is so showy.


Boa Constrictor

Boa constrictors belong to the boa and python family. Both species squeeze their prey in order to prevent the animal from taking in air, often killing their victim before eating it whole. They are nonpoisonous. Boas live all over the world while pythons are indigenous to Asia and Africa. Most of them live in caves or other cool places, but have been known to find themselves in cities as people invade their space by building homes and farms.



The anaconda has been the topic of many movies which would lead people to believe that they are very aggressive and attack people. But the truth is that they like to be alone and are often difficult for scientists to study because they are so hard to locate. They live in or near the waters of South America and eat amphibians and birds.

Snake Myths

A fear of snakes can be healthy since it helps us be aware and cautious when we're passing through territory that might have snakes dangerous to us. But we also tend to invent “facts” that aren't true about things we fear. Here are some invented “facts” (myths) about snakes:




Snakes must be coiled up to strike.

coiled snake

A snake only coils as a defense mechanism and to see more clearly. They do not have to be coiled when they strike. They strike quickly and can reach a victim at a distance nearly equal to the length of the snake's body.

Snakes are mean.

Sinister snake

A snake lives in a world where they must defend themselves. They are not out to get people. They are just defending themselves because a human is so much larger than they are.

Rattlesnakes always rattle before they strike.

Rattle snake

A rattlesnake rattles to warn if they are afraid they have been seen, but studies show that if they are camouflaged, they might not rattle.

Only poisonous snakes bite.

Snake biting itself

Any snake can bite, and although the bite of a non-poisonous snake has no venom, it can cause infection.

The number of rattles on a rattlesnake tells the age in years.

Snake with a birthday cake

A rattlesnake can shed its skin several times per year, so although this does create a new rattle with each shedding, it is not representative of a year's time period. Older rattlesnakes can also lose rattles in battle or while hunting food.

Snakes make good pets.

pet snake

Snakes are a very popular house pet for many families. The truth is however, reptiles carry salmonella. Salmonella is a kind of bacteria that can cause serious illness in people. Snakes and other reptiles can spread salmonella to people even if they come from pet stores.

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