University of Missouri Extension

G9450, Revised June 2003

Snakes: Information for Missouri Homeowners

Robert A. Pierce
Extension Fish and Wildlife Specialist
Department of Fisheries and Wildlife Sciences

Few animals are more disliked or misunderstood than snakes. Irrational fears and feelings that people have about snakes come from misunderstandings and superstitions handed down from one generation to another. Snakes are not mysterious at all, and their colorful, fascinating life histories do not justify the anxiety many people feel about them.

Most of the 50 species and subspecies of snakes found in Missouri are harmless (a subspecies is a geographic race of a species). The five species of poisonous snakes found in the state include the Osage copperhead, western cottonmouth (water moccasin), western pygmy rattlesnake, massasauga rattlesnake and timber rattlesnake. Although you should respect poisonous snakes and approach them with caution, most snakes you may encounter in an urban environment are harmless and beneficial because they eat insects, mice and other rodents.

This publication seeks to dispel misinformation about snakes and to help homeowners control potential snake problems around residences.

Biology and habits

Snakes are reptiles — a group that also includes lizards, alligators and turtles. Reptiles have been around for millions of years.

Snakes are ectotherms, which means they regulate their body temperature by taking heat from their environment or by giving off heat. Because their body temperature is affected by environmental temperatures and varies with surrounding conditions, snakes are inactive during hot seasons (aestivation) and cold seasons (hibernation). Snakes may go for several weeks without eating because of frequent periods of inactivity.

Because snakes are cold-blooded, they must rely on behavior to regulate their body temperature. During the hot part of the day, snakes move to shaded areas. On cool days, they sun themselves on rocks or in warm and open areas. Snakes often seek out paved roads because they are attracted by the heat from the road surface.

Because snakes have a backbone, they are classified in the same group (vertebrates) as fish, mammals, birds and humans. The snake's skeletal system is unique. Snake bones are light and highly movable. The lower jaws and skull are connected by a piece of stretchy material called a ligament. This allows the snake to open its mouth wide and move each jaw independently. Thus, a snake can swallow prey much larger than its head.

Snakes do not have legs, ears or eyelids. Often the sex organs of a snake protrude from the anal plate area, and some might think these are legs.

Snakes use their forked tongues to smell. Their tongue constantly flicks to pick up airborne particles and odors. Once it detects these aromas, the snake inserts its tongue into two holes on the top of its mouth (Jacobson's organ), where its brain interprets the smells. If the snake detects food and is hungry, it will pursue the animal.

Contrary to popular belief, snakes are not slimy. In fact, they feel dry to the touch. The snake's scales and skin help keep it from losing moisture from its body. Snakes shed their skin and eye covering together.

With the warmth of spring, snakes emerge from their winter quarters and search for food and mates. After mating, the male and female snakes separate. Each goes its own way to forage for food until the fall.

Some snakes lay eggs in a damp, protected area where they will hatch in about two months. Other snakes hatch eggs inside the body. Copperheads, rattlesnakes, cottonmouths, garter snakes and water snakes give birth to live young. Once the young have been hatched or born, they are able to take care of themselves. If you find snake eggs around your home or garden, they were laid by a harmless snake.

All snakes are predators, and many are particular about what they eat. Rat snakes eat rats, mice, voles and bird eggs. Water snakes feed primarily on dead, diseased or injured fish. King snakes feed on other snakes, mice, young birds and bird eggs. Some small snakes (the rough green snake) eat insects while others (earth snakes and worm snakes) eat earthworms, slugs and salamanders. Toads are the favorite food of the hognose snake.

When people encounter a snake, they often corner it. Then the snake will hiss loudly, open its mouth in a threatening manner, coil up and strike at the individual or bluff by advancing toward the person. These behaviors are designed to scare off an intruder. They lead, however, to a common misconception that snakes charge or attack people. In most cases, a snake reacts only if it feels threatened. Usually, it crawls away if it can reach cover safely. One exception is the male black racer, which may chase larger animals, including humans, when it is defending its breeding territory.

Snake habitat

Snakes like to live in damp, dark, cool places where food is abundant. Likely places to find snakes around homes include

Identification of poisonous snakes

All of Missouri's poisonous snakes are members of the pit viper family, and you easily can distinguish them from harmless snakes. Three ways exist to distinguish poisonous snakes in Missouri:

Identifying a poisonous snake by its pupilsFigure 1
Identifying a poisonous snake by its pupils.

Identifying a poisonous snake by its tailFigure 2
Identifying a poisonous snake by its tail.

Other features may help you identify a poisonous snake at a distance

Color and pattern Figure 3
You can learn to distinguish poisonous snakes from nonpoisonous species by their color and pattern.

Snake bites

Snake bites occur despite precautions. Most first-aid texts do not encourage victims of snake bites to kill the snake. The victim may wind up being bitten a second time. Whether the snake is poisonous or harmless can be determined within a few minutes if the victim begins to experience pain and swelling at the bite. Also, all snake bites normally are treated with crotalid antivenom, applicable to all poisonous species in the state, so identifying the snake is not as important as it once may have been.

You should ask your doctor during a regular visit for advice regarding snake bites.

If you are bitten

Beneficial aspects of snakes

Before deciding to kill a snake in your yard or garden, consider the many benefits of snakes. Snakes are one of nature's most efficient mouse traps; they kill and eat a variety of rodent pests. Although snakes will not eliminate pests, they do help keep their numbers in check. Some harmless snakes (king snakes, milk snakes and black racers) eat other snakes, including poisonous ones.

Snake venom has been used to develop a variety of human medicines. One type of high-blood-pressure medicine was developed using information based on chemical secrets contained in snake venom. Researchers are conducting studies using snake poisons in developing treatments for blood and heart problems. Snake venom also is being investigated for controlling some types of harmful bacteria.

Snakes in Missouri are protected by state law. The Wildlife Code of Missouri treats snakes, lizards and most turtles as nongame. This means there is no open season on these animals, and it is technically illegal to kill them. Of course, realistic exceptions exist, such as when a poisonous snake comes in close contact with humans, which could result in someone getting bitten. You should get a collecting permit from the Missouri Department of Conservation before attempting to catch and keep a snake.

Controlling snake problems

The most effective and lasting method for discouraging snakes is to modify the environment so they find it unattractive.

Habitat modification
Modify the environment by removing the snake's shelter and its food source.

Chemical control
No fumigants or toxicants are federally registered for snake control. The potential for development of such snake controls is complicated by the diet, body temperature and other biological aspects of snakes.

Snake-proof fence Figure 4
A snake-proof fence can keep snakes from entering an area, such as the child's play area shown above.
 

Exclusion
Snakes enter buildings in search of cool, damp, dark areas or places where rodents and insects abound. To prevent these unwanted guests from entering your home, check the foundation for cracks and openings one-fourth inch or larger.

GlueboardFigure 5
Large glueboard to catch snakes.
 

Removal from inside buildings

Occasionally, homeowners find a snake inside the home, usually in a basement or crawl space. Snakes are attracted to these areas by the warmth on cold days and the shade on hot days. They may enter through a hole around the foundation or an open or loose door or basement window. If this occurs, you need to get the snakes out, then seal the holes.

You increase your chances of capturing a snake in the house by placing in areas where snakes have been seen some rumpled, damp cloths covered by dry cloths. Snakes are attracted to these areas. You then can remove the whole works, snake and cloths, or capture the snake individually. A good way to remove a snake is to sweep it with a broom into a large bucket.

Another effective way to capture snakes is to use a glueboard. You can buy these in a variety of places, such as agriculture-supply or hardware stores. Most small snakes can be captured using a single glueboard placed against a wall. Keep the board away from pipes or other objects a snake could use for leverage to escape.

A more elaborate arrangement is necessary to capture larger snakes (Figure 5). This type of glue trap can be made at home with purchased glueboards. It is constructed of one-quarter-inch plywood cut into 16-inch by 24-inch sections. Drill a three-quarter-inch hole in one corner to allow removal of the board by using a hook on the end of a long stick. Fasten two to four glueboards (or use bulk glue) along one side of the plywood board. This type of trap, when placed against a wall, is capable of capturing snakes up to 5 feet or 6 feet long.

Use glueboards only indoors or under structures where children, pets or other wildlife cannot reach them. The glue is quite messy and hard to remove. Use common cooking oil or vegetable oil to remove animals from the glue. Be sure to seal any holes or entrances so the snakes do not return. Another option is to use the newly developed snake trap called Snake Guardª. It should be used like a glueboard.

Remember, snakes are an important part of our natural world. The best approach in managing snake problems, where possible, is to leave the animal alone.

Other sources of information

The Missouri Department of Conservation produces publications and videos, a number focusing on snakes:

For price and availability of the publications and videos listed above, contact the Missouri Department of Conservation at P.O. Box 180, Jefferson City, Mo. 65102.

Several field guides also are available, including:

Outdoor prevention and control tips

Indoor prevention and control tips


 

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G9450, revised June 2003

G9450 Snakes: Information for Missouri Homeowners | University of Missouri Extension

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