Deer in Spring Landscape

Venomous Snakes in Maryland

By Eugene Deems and Duane Pursley

Snakes are rarely aggressive towards humans. If you encounter a snake simply maintain a safe distance and move away from it, or allow it to move away from you.

Snakes are among the most feared and hated creatures in the world, despite the great amount of material that has been written about their beneficial activities.

In reality, they are a complex, interesting, and colorful portion of Maryland's native wildlife and their ecological value is immeasurable. Hopefully, environmental education will dispel many myths associated with our reptile fauna.

Probably the greatest economic value of these reptiles is the service they perform in pest control through their feeding habits. While all groups of reptiles contribute to this service, some species of snakes are particularly beneficial. The pit vipers, as well as both species of black snakes, the Eastern king snake, the corn snake, and the milksnakes are well known rodent predators. King snakes may also feed on the poisonous pit vipers while the smaller snakes and lizards consume large quantities of insects.

Only two of the twenty seven kinds of snakes inhabiting Maryland are venomous:
the copperhead and timber rattlesnake.

Northern Copperhead
(Agkistrodon contortrix mokasen)

Photo of coiled Northern Copperhead courtesy of John White
Northern Copperhead
(Agkistrodon contortrix mokasen)

Photograph by John White

This is one of the two venomous snake species in Maryland. The color is a rich, reddish, brown with a series of darker hourglass markings down its back. Its head is usually a bright copper color and its belly is pinkish. It seldom exceeds three feet in length. It has a single anal plate and keeled scales. This is the only Maryland snake that has dark dorsal markings which are narrow on the back and broad on the sides. Copperheads exist throughout the State in remote rocky, wooded areas where they feed on small rodents and other warm-blooded prey. Occasionally, they will feed on aquatic animals. Females give birth to approximately 12 live young which are 8-10 inches in length.

Timber Rattlesnake
(Crotalus horridus horridus)

Photo of coiled Timber Rattlesnake courtesy of Ed Thompson
Timber Rattlesnake, Crotalus horridus
Photograph by Ed Thompson

This venomous reptile is the only species of snake in the State with a segmented rattle at the end of its tail. It has brown or black cheveron-shaped markings on a yellow background, down its back. The background color may vary from a bright yellow to a dull gray. Entirely black specimens also occur. This snake rarely exceeds six feet in length. It commonly occurs in the remote rocky, mountainous sections of the State. Females may give birth to as many as 12 live young which are approximately 9-10 inches long. The pit viper habit of congregating at dens, creates a situation wherein considerable numbers of rattlesnakes and copperheads can be seen at one time.

Major Identification Features

non-venomous snake

  1. Round pupils

  2. No sensing pit

  3. Head slightly wider than neck

  4. Divided anal plate

  5. Double row of scales on the underside of the tail

venomous snake

  1. Elliptical pupils

  2. Sensing pit between eye and nostril

  3. Head much wider than neck

  4. Single anal plate

  5. Single scales on the underside of the tail

A Guide to Maryland's Herps - Reptiles & Amphibians

Non-venomous snakes are often erroneously identified as venomous. Many publications have noted five sets of characteristics which may be used to separate Maryland's non-venomous snakes from its pit vipers -- the timber rattler and copperhead. The five features commonly referred to are: the shape of the eye pupils, tail, head, location of the sensory pits, and scale patterns on the underside of the tail.

From a practical viewpoint, an understanding of only one of these features is necessary for a determination of the venomous status of any resident snake. Since most snakes are identified after they are killed, the tail scale patterns are the most valuable characteristics to learn. They are totally reliable, easy to see, and often the most intact part of a reptile that a human being has encountered. Many people have trouble distinguishing the elliptical eye pupil in a pit viper from the round one in a non-venomous snake. The layman may also have difficulty determining the presence or absence of the sensory pits inherent to rattlers and copperheads. Several species of snakes, have relatively spade-shaped heads which are wider than their necks; but these features are more distinctive in the rattlesnakes and copperheads. The illustration clearly shows the different characteristics of venomous and non-venomous snakes in Maryland.

Controlling Snakes

Snakes occasionally enter houses, sometimes by accident, sometimes when searching for hibernation quarters or mice. These are almost always harmless, non-venomous kinds.

Snakes can pass through extremely small openings and they usually enter buildings near the ground level. Cellar doors, windows and screens must fit tightly. Walls and floors should be inspected for crevices. Spaces around pipes that go through outside walls should be plugged. Galvanized screen can be fastened over drains or ventilators or even over larger areas of loose construction which would be difficult to snake proof in any other way.

Snakes can be discouraged from staying around grounds and buildings by eliminating food and cover that is attractive to them. Most snakes like to feed on rodents; therefore, it is advisable to make all buildings rodent proof.

Closely mowed lawns and fields are less attractive to snakes than areas of tall grass, weeds or brush. Snakes seek food and cover under boards, flat rocks, trash piles, and similar materials. Eliminate such shelter and the premises will be much less inviting to them. This approach may not be practical on farms, but it is of real value around suburban dwellings, summer homes, and resorts. Along water margins, snakes sun on logs or over-hanging brush They hide under driftwood, rocks, and boats and are seldom seen on clear, open beaches where they are exposed to direct sunlight and predators.

You Can Prevent Snake Bites

The best snakebite treatment is to avoid getting bitten. The following suggestions should help you stay clear of venomous snakes.

  1. Learn to identify, by sight, the copperhead and timber rattlesnake.

  2. When hiking or camping in areas where snakes might be found, watch where you put your hands and feet. Watch where you sit and where you place your sleeping bag.

  3. Wear suitable clothing, when hiking through tall grass or heavy brush, wear long pants and heavy boots.

  4. Avoid rock piles, stacks of old boards and brush in wooded areas, as snakes use such areas frequently.

  5. Never handle "dead" venomous snakes, they may not be completely dead.

  6. Leave live snakes alone. DO NOT attempt to capture or kill them.

What to do if a Snake Bites

The Maryland Poison Control Center states that from 2-6 people receive venomous snake bites in Maryland annually and that people rarely die from snake bites, even without medical treatment. Venomous snake bites are more serious in children, since the ability of a body to absorb venom without fatal results varies with the person's weight or volume.

If you should get bitten by a venomous snake, contact your physician or go to the nearest hospital immediately.

According to the American Red Cross, these steps should be taken:

  • Wash the bite with soap and water.

  • Immobilize the bitten area and keep it lower than the heart.

  • Get medical help.

The following is a list of What NOT To Do:

  • No ice or any other type of cooling on the bite. Research has shown this to be potentially harmful.

  • No tourniquets. This cuts blood flow completely and may result in loss of the affected limb.

  • No incisions in the wound. Such measures have not been proven useful and may cause further injury.

Illustration by Tom Allen