SNAKES
Order Squamata
Suborder Serpentes



Above, L-R
Figure VI-1, A yellow stripe accents the lower sides of the queen snake.
Figure VI-4, The eastern smooth green snake can easily become lost among tall grasses.
Figure VI-3, A timber rattlesnake peers from the shelter of a burned out stump on a warm autumn day.


Above, L-R
Figure VI-5, The northern ringneck snake wears a golden or yellowish necklace around its neck.
Figure VI-2, By the time ferns cover the forest floor, the timber rattlesnake has left this winter den for more open areas.
Mention the word "snake," and many people cringe, shudder, scream, run or all of the above. Snakes could be the most maligned, misunderstood, feared and hated animals known to man. Almost from the beginning of mankind (engravings of snakes were found on crafted antlers dating back to 8,000 B.C. to 15,000 B.C.), snakes have been a source of mystery, myth, folklore, fascination and fear. From the ancient story of Adam and Eve in the Garden of Eden to the present day, snakes have been considered fascinating—but a doer of dirty deeds. To ancient Hebrews, these serpents were the personification of evil, and early biblical references portrayed snakes as the sin-offering Satan.
Still, snakes have been popular symbols for countless centuries. The ancient Greeks believed that snakes had supernatural healing power, and even today the medical profession is symbolized by two snakes coiled around a winged staff. Called a Caduceus, the snake-encrusted staff originally was carried as a symbol of authority by Mercury, the messenger god of Roman mythology.
The elaborate headdresses worn by the pharaohs of Egypt were embedded with the likeness of snakes. The ancient rulers were convinced that snakes were a source of power and protection from harm.
Even colonists in the early days of this nation emblazoned a rattlesnake on their first flag and on several others afterward. With the words "Don't Tread On Me," the rattlesnake (with 13 rattle segments, one for each colony) graphically and boldly portrayed the determination of a fledgling country to become independent. In a letter that appeared in Bradford's Journal of December 27, 1775, it was written that "ancients regarded the serpent as an emblem of wisdom, and . . . of endless duration." It went on to note that "the rattlesnake is found in no other quarter of the globe than America, and it may therefore have been chosen on that account to represent . . . the Revolutionary armies."
Regardless, many people continue to regard snakes only as a menace and a symbol of repulsiveness and evil. There are some who believe that the fear and hatred most people feel toward snakes is not inherent, but is taught, handed down from generation to generation. True, some date back to ancient biblical references. But what young Cub Scout, about to leave for his first-ever outing, hasn't been admonished by mother as he goes out the door, "watch out for snakes." And even as we get older, one angler might caution another about to embark on a fishing trip into a not-so-remote wilderness area to "be careful of the snakes in there." We're faced, it seems, with constant reinforcement that snakes—all snakes—are something to be feared.
Through a better understanding of these reptiles, fears can be overcome, mysteries unraveled and hatred diminished Armed with more knowledge, all of us can respect these animals for the important part they play in helping keep nature in check. There's no question that care should be exercised when in the presence of venomous snakes—they can be harmful. But given their due respect and the understanding that their venom sometimes is used as a means of defending themselves and in obtaining prey, even these snakes in most cases can be left to go their own way. They, like all animals, should be allowed to fulfill the mission nature intended for them as an integral component within a complex ecosystem.
There are some 2,700 snakes known in the world today. Snakes inhabit all the continents except Antarctica. There are 11 families of snakes in all, five of which have representative species in the United States. In Pennsylvania, two families appear, with 16 genera accounting for 21 species; only three of these are venomous.
Ancestors of today's snakes apparently evolved from lizards. It's believed lizards went underground where they escaped the huge appetites of the dinosaurs. Though safe from monstrous predators, over eons of time these lizards lost their limbs, hearing and to some degree their eyesight. Perhaps confined to close quarters, snouts became narrower and that meant smaller, non-chewing teeth. As they became more slender, internal organs also underwent changes resulting in a less efficient heart and the loss of one lung. The result of these changes, which occurred over countless years, is the snake much as we know it today.

Snakes are generally described as long and slender (See Figure VI-6), perhaps elongated is a better term, and without limbs (although some species still have hidden vestiges of legs not completely lost during their evolution from lizards). Snakes do not have movable eyelids and there are no external ear openings. Their bodies are covered with scales that differ somewhat between species. Some scales are smooth (completely flat) while others have a ridge that extends down the center of the scale and are said to be keeled (See Figure I-10). The scales are dry and help prevent dehydration. They also aid in protecting the snake from physical injury. The type of scales, whether they are smooth or keeled, can help sort out one snake from another. The anal plate, a scale located near the vent, may be divided into two segments or appear as a single scale. This, too, can help identify certain snakes (See Figure VI-7). The scales on the underside of the tail help distinguish our pit vipers, which have a single row of scales, from our non-venomous snakes which have two rows of scales (See Figure VI-7).
Figure VI-7

Snakes have a highly developed sense of balance, a trait especially helpful to those snakes considered arboreal. While some may spend a majority of their time in trees, other terrestrial species seldom, if ever, leave the ground. Still others are considered at least semi-aquatic and spend a certain amount of time in the water. Some of these reptiles are nocturnal. Others are considered diurnal and crawl about during the day. All are carnivorous and swallow their prey whole. Snakes do not feed on plants or plant parts, so grains, seeds, vegetables and so forth are never touched.
Snakes may mate anytime from spring to fall. The male locates the female by scent, and during breeding fertilization is accomplished internally.
Among our snakes, egg laying is probably the most common means of reproduction, although some species retain the eggs or young snakes inside the body during the embryo stage. In this case the snakes are born alive (See Figure VI-8).
There are several advantages to keeping the young inside the mother during the development stage. Protection from predators is better ensured and atmospheric fluctuations that could cause eggs to dehydrate or rot are minimized. Development is also enhanced because the mother can better regulate the temperature of the embryo by avoiding extremes of heat or cold, moving from one area to another as necessary to ensure proper and speedy growth of the expected progeny. The eggs, which remain inside the female, lack a calcified shell and in fact are more a sac-like membrane.
In most cases after the young are born, or the eggs are laid, the parent snake departs immediately and the juveniles are left to fend for themselves. Fortunately, young snakes are self-sufficient from the very beginning and can manage quite well without their parents. In some cases, a quantity of unused egg yolk may remain in the body. Thus, the young snake has an internal source of nourishment to carry it over until it is able to forage for itself.
Some snakes, usually the smaller species, feed on worms, insects and other small prey. Larger snakes feed on rodents, fish, frogs, birds and a variety of mammals. Different species of snakes employ different methods in obtaining and swallowing food. The smaller snakes simply grab the prey with their teeth and swallow it live. Others snatch their prey with their teeth and constrict it until it dies from suffocation. Still others have adapted poisons to kill their prey before eating it.
All snakes have numerous teeth, but in most cases they are designed only for grasping and holding. The teeth have not been developed for chewing, so the snake is unable to carve its food into bite-sized pieces before eating it. Thus, it is forced to swallow its prey whole. This process has fascinated people for ages because the prey sometimes exceeds the diameter of the snake. But again, nature has constructed a jaw that permits this reptile to engulf prey many times larger than itself.
The lower jaw is not solidly fused in front but is held together instead by an elastic ligament that allows the jaw to part. This jaw is only loosely connected to the skull. The upper jaw is immovable, but the bones to which the upper teeth are attached can be moved slightly. With the prey held firmly in the mouth by many sharp, rear-pointed teeth, either side of the lower jaw can be loosened, which enables the head to move forward, up and around the prey, a small step at a time. The mouth now opens in a wide gape, each side works alternately and independently of the other and by so doing pulls or "walks" the food into the mouth (See Figure VI-9). As the food is forced into the back of the mouth, the throat expands because of a loose assemblage of head bones, and the food enters the throat. At this point, powerful muscles work the food into the stomach where strong digestive juices take over, even to the extent of absorbing bones. The skin is extremely elastic, and when distended, allows prey to be taken into the stomach where a large bulge shows that the snake has just enjoyed a meal. A movable windpipe, which extends from the throat to the end of the lower jaw, permits the snake to swallow large prey and breathe at the same time.
A snake's skin does not grow as the body matures and becomes larger. Therefore, the skin must be shed, a process called ecdysis. Snakes may shed for the first time only a few days after being born or hatched. As they age, shedding may occur from four to six times a year at first, slowing to only once or twice a year after they reach maturity.
As the shedding process begins, the snake's general coloration becomes dull and the eyes become cloudy as a molting fluid fills the space between the old and the new skin. This may occur 10 days to three weeks before the actual shedding takes place, and the snake may be partially blind during a portion of this process. As the skin becomes slack, it is first worked loose at the chin and snout as the snake rubs against a solid object. With the skin on the head loosened, muscular contractions take over and the snake slips out of the skin, turning it "inside out" in the process.
Snakes have no eardrums or external ear openings. They apparently were lost during the evolutionary process. Even though they are unable to hear as can most other animals by sensing air-borne vibrations, snakes are sensitive to contact vibrations and in that sense have a well-developed sense of "hearing." A bone called the columella, transmits vibrations from the lower jaw into the inner ear embedded in the side of the skull. It's an effective method. Approaching footsteps are easily detected and the snake often escapes long before it might be seen by the approaching intruder.
Several snake myths and folklore have been fabricated on the "unblinking stare" of these serpents, that their steady gaze has caused their prey—and perhaps even humans—to become hypnotized. Although snakes do not hypnotize, it is true that they do not blink. They can't blink. They are not equipped with movable eyelids. Instead, the cornea is covered and protected by a transparent eyecap that actually is a fixed, circular scale shed and renewed along with the rest of the skin and scale covering. This eyecap, called the brille, is an important protective device and prevents injury when the snake burrows, swims through the water or slithers quickly through dense vegetation.
Although its eyesight is keen and sensitive to movement over a wide range, distant vision is not so well-defined because it lacks a refined method of focusing.
The tongue seen darting quickly in and out of the mouths of snakes also has been a source of myth and tall tales. It is not a needle-like projection and cannot be used to penetrate the skin of prey, a nearby foe or humans. It is not capable of injecting venom or any other toxic substance. It is, in fact, harmless.
The tongue is moist and quite delicate, and it's an important part of an extremely sensitive system used for tasting and smelling. (Some lizards and salamanders have similar systems.) Though the snake's sense of taste is not highly developed, the ability to smell (although perhaps not in the same sense as humans) is excellent.
The tongue is forked and can dart in and out of the mouth through a notch in the upper jaw even when the mouth is closed. When extended, the tongue picks up microscopic particles from the air and brings them into the mouth. Here, the double-tipped tongue quickly places the samples into two small cavities embedded in the palate at the rear of the mouth. The cavities lead to a chemical receptor called the Jacobson's organ (See Figure VI-10). The Jacobson's organ contains sensory cells able to identify chemical particles and transmits these sensations of taste-smell to the brain.
When not collecting chemical information, the tongue is withdrawn into a narrow sheath on the floor of the mouth located just in front of the breathing tube. When disturbed or in some other way its interest is aroused, the snake's tongue moves rapidly and frequently between the Jacobson's organ and the air outside. With this well-developed sense of "smell" the snake detects the presence of enemies, finds food and locates its mate.
How Does a Snake Get from Here to There?
In spite of having lost its limbs as it developed over millions of years, the snake as we know it today in Pennsylvania is able to move about efficiently and when needed, quickly. Several methods or a combination of means can be used.
The most important body structure allowing snakes to be as mobile as they are, is the very large number of vertebrae in the spine, or backbone. Counted in the hundreds, each vertebra is attached to a pair of ribs curving downward and around the body. The ribs in turn are attached with muscle to large scales, or scutes, on the belly. These scales and the ribs are important if a snake is to be able to move quickly and effectively through its surroundings.
When not in any hurry, a snake uses a caterpillar-like movement called rectilinear locomotion (See Figure VI-1Ia). This method of locomotion allows the snake to move in a straight line. To do so, the scutes (those belly scales) move in groups, alternately gripping and advancing; not all the scales on the belly move at the same time or in unison. Instead, several scutes in a group grip the surface over which the snake is moving and push forward, while the next group of scales is picked up slightly and moved forward. The second group of scales then grips the surface as a third group advances to be laid down in preparation to provide the grip, and so on. The effect is similar to the familiar method used by a caterpillar.
When the snake needs to move more rapidly, it uses another, more effective method, called serpentine locomotion. In this case, a series of writhing undulations is used in which the sides of the body are pushed against some solid object such as a tree, stone or even the rough surface of the ground. The unmoving objects provide a hold or push-point for each rib as it passes (See Figure VI-I 1b). As the snake moves, it alternately contracts and relaxes the muscles attached to the vertebrae, first one side, then the other. The result is a bending of the body into a series of S-curves (See Figure VI-12), providing pressure points on the back side of each body curve. As the curved body pushes against the stable object, the snake is propelled forward in a wavelike motion. It is thought that the scutes are also used to help pull the body forward while gripping the surface.
By using either the rectilinear or serpentine method of locomotion—or a combination of the two—snakes can negotiate nearly any surface and move about almost anywhere.
The liquid movement of snakes has been a source of wonder and amazement for many people over countless years. To become mobile, snakes have developed a specialized and effective bone-muscle-scale construction.
One of the most important elements in the enhancement of this reptile's locomotion was the growth of a large number of very small vertebrae. Some species have as many as 400 of these miniature spinal bones, which allow the snake's fluid movement and flexibility. Except for the tail, these vertebrae have a pair of ribs attached to them. Muscles in turn connect the ribs to large belly scales, called scutes. The scutes are able to grip the surface over which the snake is moving, enabling it to travel over a variety of terrain and climb trees.
The ribs and scutes do not all move together as the snake propels itself forward. As scales on one part of the belly move forward, others are just beginning to move backward, to be picked up and placed in a forward position once more. The scales, as they move back and forth, grip the surface and produce a caterpillar-like movement, pulling the snake along at a leisurely pace with the body in a straight line. The pace is silent and slow, ideal for stalking prey.
However, when the snake is disturbed or wants to move quickly it uses a series of undulations in an accordian-like form of locomotion. By drawing the body into several S-curves, successive sides of the body are pushed against solid objects such as rocks, plants or the rough ground. This serpentine effect is produced with alternate contractions and relaxations of the muscles on each side of the body. Relaxing the muscles and ribs attached to one side of the vertebrae while contracting the opposite allows the body to flex or bend. This S-shaped wriggling continues in a wave-like pattern as the curves alternately form and straighten out. This "curve-push-straighten-out" series of movements can be performed rapidly and it quickly propels the reptile forward.
Colubrid snakes
(Family Colubridae)
Eastern worm snake—Carphophis amoenus amoenus
Kirtland's snake—Clonophis Kirtlandii
Northern black racer—Coluber constrictor constrictor
Northern ringneck snake—Diadophis punctatus edwardsii
Eastern ratsnake—Pantherophis alleghaniensis
Eastern hognose snake—Heterodon platyrhinos
Eastern kingsnake—Lampropeltis getulus getulus
Eastern milksnake—Lampropeltis triangulum triangulum
Northern water snake—Nerodia sipedon sipedon
Rough green snake—Opheodrys aestivus
Eastern smooth green snake—Opheodrys vernalis vernalis
Queen snake—Regina septimvittata
Northern brown snake—Storeria dekayi dekayi
Northern redbelly snake—Storeria occipitomaculata occipitomaculata
Shorthead garter snake—Thamnophis brachystoma
Eastern ribbon snake—Thamnophis sauritus
Eastern garter snake—Thamnophis sirtalis sirtalis
Earth snake—Virginia valeriae
The colubrid family is the largest of all the snake families and contains all of Pennsylvania's non-venomous species. Three-fourths of the world's 2,700 snakes belong to this family. There are 18 species from this family in Pennsylvania, representing 13 genera. The colubrid family includes arboreal snakes, and others that seldom, if ever, leave the ground. The state's water snakes are also included in this family.
Generally, these snakes all have a head that is tubular to somewhat flattened. The head is normally as wide as the neck (See Figure VI-13), perhaps a bit more so in some species. The pupils of the eyes are round in Pennsylvania species (See Figure VI-14). The head is covered with large scales arranged in a regular pattern. The scales across the back may be either smooth or keeled and can help in identifying several of the species (See Figure I-10). There are two rows of scales on the underside of the tail (See Figure VI-7). There are teeth on the upper and lower jaws, but these snakes do not have the enlarged hollow fangs common to the venomous varieties.
Figure VI-13

Figure VI-14


The colubrid snakes feed on a variety of vertebrate and invertebrate animals. They devour their prey whole. No vegetation is used in the diet of these snakes.
Pit Vipers
(Family Viperidae; subfamily Crotalinae)
Northern copperhead—Agkistrodon contortrix mokasen
Timber rattlesnake—Crotalus horridus
Eastern massasauga—Sistrurus catenatus catenatus
Pennsylvania has three venomous snakes. All are members of the pit viper subfamily Crotalinae of the family Viperidae and all its species are venomous. Most are stout-bodied snakes with a head that is well-defined from the neck (See Figure VI-13). Their pupils are vertically elliptical, shaped like a cat's pupil (See Figure VI-14). Most members of this family are nocturnal and bear live young. They are considered the most advanced of the snakes.
These snakes are equipped with long, hollow fangs that actually are modified teeth located near the front of the upper jaw. Their normal position is folded back along the jaw where they connect to a movable bone but swing forward rapidly when the mouth is opened in preparation to strike. Except for its tip, each fang is encased in a fleshy sheath. While only one set of functional fangs is in place, several others may be in various stages of development with replacement occurring every few weeks.
Each of these large, hollow teeth is connected by a duct running from the base of the fang to a gland located on the side of the head, behind the inner ear (See Figure VI-15). The snake usually strikes from a defensive S-curve posture. It is lightning-quick as the body straightens. The snake can strike a distance of about one-third to one-half its body length. Young snakes can strike, inflict a wound and inject venom as soon as they are born. The venom of Pennsylvania's venomous snakes is a complex mixture of proteins primarily affecting elements of the circulatory system. Tissues are destroyed by the venom and the blood's ability to clot properly is affected. Victims also find that the body's ability to fight off infection is lowered. The venom may also contain some neurotoxin, thus potentially inflicting damage to the nervous system.
Prompt medical treatment should be sought in the event of a bite. However, these snakes are able to withhold the venom if they desire, even though the fangs may have been used to inflict a bite. So-called "dry strikes" are known to occur.
Pennsylvania's three venomous species are pit vipers, so named for the deep pit located on each side of the head between the eye and the nostril (See Figure VI-14). These depressions are heat-sensitive organs able to respond to very small changes in temperature. Always alert, the organs respond to the amount of heat reaching them and help the snake detect the existence and locate the direction of a warm body. It is especially helpful at night when lying in wait for prey, because it allows the snake to locate warmblooded prey in complete darkness. Using this heat receptor, the snake locates prey that comes its way and strikes with great accuracy.
Like other snakes, pit vipers must shed their skin as they grow. In the case of the rattlesnakes, this also means adding a new segment to the rattle. A new segment is added each time the skin is shed, which could occur several times a year depending on the age of the snake. Thus, counting the number of segments on the rattle does not reveal the true age of the snake. A newborn rattlesnake has a pre-button on the end of its blunted tail. The first button is not gained until the young rattlesnake sheds its skin for the first time. The scales on the underside of the tail are in a single row (See Figure VI-7).
These snakes, like the others, are carnivorous and must consume their prey in a single piece.
Species Descriptions
Eastern Worm Snake
Carphophis amoenus amoenus
General characteristics. It's easy to understand how the eastern worm snake got its name. It resembles an earthworm and isn't much larger when you consider that adults reach only seven to 11 inches. It is one of the smallest snakes in Pennsylvania. The worm snake is a secretive animal, rarely seen in the open. If you wanted to locate a worm snake, you would have to do some serious searching.
Identification. This snake is tiny and glossy in appearance. Except for the belly, which is a bright reddish pink, the eastern worm snake is brown and unpatterned over its entire body. The head is blunt and rounded and the tail is short with a sharp tip. The scales of the eastern worm snake are smooth and contained in 13 rows. The anal plate is divided.
Range. This small reptile ranges from lower New England to South Carolina and Alabama. The known distribution of the eastern worm snake in Pennsylvania is limited to the southeast quadrant, covering about one-fourth of the state. It has not been confirmed as inhabiting areas north of the lower Poconos nor west of the Allegheny Mountains.
Habitat. Damp, often hilly woodlands are home to the eastern worm snake. It is partial to wooded or grassy hills above streams or moist ground. The eastern worm snake takes temporary shelter under rocks and decaying logs or retreats into the loose soil of its environment. During dry spells and during periods of cold weather, the eastern worm snake burrows deep into the soil.
Reproduction. The tiny eastern worm snake mates during April and May, depositing one to eight eggs in June or July. Elongated and thin-shelled, the eggs measure less than an inch. The eggs hatch in seven weeks and the emerging young eastern worm snakes are three or four inches long. Darker than the adults, they mature in three years.
Food. The eastern worm snake feeds on worms and soft-bodied insects. Its habitat normally produces sufficient food of the type preferred, so it feeds well before going into winter hibernation. Not without problems, however, the eastern worm snake is in turn preyed on by the milk snake.
Kirtland's Snake
Clonophis kirtlandii
General characteristics. This snake is one of three water snakes in Pennsylvania, but it is found only in limited numbers and considered very rare. It was named for Jared P. Kirtland, an Ohio physician/naturalist. It is the smallest of the state's water snakes, attaining adult sizes of 14 to 18 inches. Kirtland's snake reacts in much the same manner as other water snakes when alarmed, except its reaction is more pronounced. When frightened, the defense mechanism is suddenly and swiftly to flatten their bodies to the ground. Kirtland's ability to perform this feat is more developed than other water snakes, becoming almost ribbon-like in the process.
Identification. Kirtland's snake is a slender reptile with background colors ranging from brown to reddish brown or gray. The back is accented with two rows of alternating dark, squarish spots that run the length of the body. The belly is reddish and bordered along each side with a line of round, black spots. The latter is a good identifying characteristic, helping sort this snake from others that might have similar markings or reddish underparts. The scales are keeled and the anal plate is divided.
Range. In Pennsylvania, Kirtland's snake is limited to the western portion of the state, roughly following the western slope of the Allegheny Mountains. From here it ranges west through Ohio into Michigan and Illinois and south to Kentucky. It does not extend into Erie County. It is an Endangered Species of special concern.
Habitat. Unlike many water snakes that thrive in or close to a near-total aquatic environment, this water snake prefers to remain near marshy meadows, swamps or woodland ponds. It would not be unusual to find it tucked under a piece of sandstone or other flat stone in a marshy meadow. Although it swims well, Kirtland's snake is the least aquatic of the water snakes.
Reproduction. Young are born in early August to late September. It does not lay eggs, giving birth instead to live young measuring five to 6 1/2 inches long. The size of the litter varies from four to 22. When born, the belly is a deep red, becoming somewhat subdued as the snake matures.
Food. The diet of Kirtland's snake is limited to what it can find in watery or at least moist surroundings. Worms, slugs and some small fish are the main staples.
Northern Black Racer
Coluber constrictor constrictor
General characteristics. The northern black racer is often referred to as the "black snake" and is second only to the black rat snake in size. It can attain an adult size measuring three to five feet in length. The northern black racer is diurnal, which means that it is most active during the day.
In spite of its scientific name, the black racer is not a constrictor. In fact, it is among several species of snakes considered non-constricting. If picked up, however, it does have a tendency to bite, sometimes repeatedly, and is apt to thrash about violently. The unusual habit of rapidly vibrating its tail against dry leaves has probably startled a hiker or two. One's first reaction to the buzzing sound produced as the tail strikes the crisp surface of the leaves is "rattlesnake." If nothing else, this false alarm heightens the senses of the trail walker. Although usually quick to flee, the black racer can become a fierce fighter when cornered or somehow made to feel trapped. Left to itself, it is harmless.
Identification. The black racer grows to become quite long but retains a slender appearance. It is fast, able to cover a lot of ground in a short time, and it is an agile climber. The northern black racer is slate black above and below, with an almost satiny luster. There is usually a small patch of white on the chin and throat. When born, the young racer is gray and marked with dark spots on the sides and with dark gray, brown or reddish-brown blotches streaming down the middle of the back. This pattern becomes less distinct as the snake grows, and by its third summer it has taken on the shiny single color of the adult. By then it is probably 30 inches long. The scales on the northern black racer are smooth and can be compared to the keeled scales of the black rat snake. The anal plate is divided. The head is narrow and the eyes show the yellow lens common to diurnal snakes.
Range. This long reptile can be found from Maine to Georgia and Alabama. It extends as far west as Tennessee. The northern black racer is a fairly common snake and is distributed statewide in Pennsylvania.
Habitat. This snake is at home in a variety of habitats. It can be found in abandoned fields, grassland, open woods or on wooded hills strewn with rocks. Anglers might see it moving silently along the grassy banks of a stream. The racer spends most of its time on the ground, but it is a good climber, retreating to the branches of a serviceberry or other small tree or shrub. Open areas that are fairly dry appeal to the black racer when it is time to bask in the sun. Dens for hibernating often are found on a rocky hillside and sometimes are shared with other species of snakes.
Reproduction. The northern black racer begins looking for a mate in April to late May, and by mid-June to August the female deposits from five to nearly 30 eggs in a rotting tree stump or sawdust pile. Sometimes the female might find a tunnel burrowed into the soil by a groundhog or other mammal in which to lay her eggs. The eggs are white and leathery to the touch with a rough, granular texture. They are elongated and one to two inches long. The juveniles emerge in six to nine weeks and are eight to 13 inches long, about one-quarter-inch in diameter.
Food. When hunting, the black racer moves swiftly through the grasses, its head elevated above the rest of the body. It hunts down and consumes large insects, lizards, small rodents, other mammals and even other snakes. When possible, the racer preys on birds and their eggs (the ground-nesting killdeer could easily be a potential target) and occasionally takes frogs and salamanders to alter its diet, or perhaps as a last resort to finding a meal.
Northern Ringneck Snake
Diadophis punctatus edwardsii
General characteristics. The northern ringneck snake is a secretive animal, not often seen even by persons who spend a great deal of time outdoors. It usually moves about after dark, making it even less likely to be observed. This relatively small snake is harmless, although it can emit a pungent, unpleasant-smelling musk that may help repel an attacker.
Identification. The ringneck snake in Pennsylvania reaches adult sizes of 10 to 24 inches while maintaining a slender build. Its distinguishing characteristic is the golden or yellowish ring that encircles the neck. The back and sides are usually gray, but at times can be black or even brownish. The belly is almost always a uniform yellow, although at times it may have a center row of black dots. The anal plate is divided and the scales are smooth. The smooth scales help distinguish this snake from the juvenile northern brown snake, which also has a collar but which has keeled scales.
Range. This reptile is found from Nova Scotia to Georgia, west to Wisconsin and down the Mississippi Valley. The northern ringneck snake is found throughout Pennsylvania and is partial to moist areas.
Habitat. It is more at home in a forest than it is in grassland, and a rocky, wooded hillside could easily host this unassuming reptile. It seeks cover under flat rocks and logs or might even wriggle beneath the loose bark of a dead oak.
Reproduction. The ringneck snake mates in the spring or fall. Two to six elongated white or yellowish eggs are laid in June or July, sometimes in communal nesting sites among decayed logs or rocks. Initially about one inch long, the eggs increase in size after being deposited. They hatch in about eight weeks, releasing juvenile ringneck snakes four to six inches in length. The snake matures in two to three years.
Food. At mealtime, the ringneck snake partially constricts its prey before attempting to swallow it. Salamanders are an important part of its diet, but the ringneck snake also takes worms, slugs and lizards. Even newborn snakes can be targeted by a hungry ringneck snake. Insects round out a somewhat varied diet.
Black Rat Snake
Elaphe obsoleta obsoleta
General characteristics. This is the familiar "black snake." The black rat snake is the largest of 21 species generally recognized to be indigenous to the state. Adult lengths of 42 to 100 inches have been recorded. The black rat snake is active during the day throughout the cooler months of spring and autumn. As the long days of summer grow hotter, it becomes more nocturnal in its movements, resting in a cool retreat as daytime temperatures climb. The black rat snake is a powerful constrictor. It uses this physical strength to subdue its prey by suffocation. Musk glands located in the vent can emit a foul-smelling fluid, a defensive trait common among snakes.
Identification. The black rat snake is plain, shiny black. The skin between its scales may be bluish white, yellow, red or orangish, although this coloration is not always evident. The belly of the black rat snake is an even shade of white or yellow with darker mottling of gray or brown. The belly becomes more slate gray as it approaches the tail. The chin and throat areas are a toneless white or cream. The head of the black rat snake is clearly defined in relation to the neck and body. A flattened snout seems to emphasize the head's squarish appearance. Also, the black rat snake does not have the rounded or tubular body common to most snakes. Its belly is flat, meeting the sides at an angle. If one could imagine it viewed from the end, it would resemble a loaf of bread rather than appear circular. The black rat snake has a divided anal plate. The scales are only weakly keeled.
The young black rat snake is deeply patterned down the back and onto the tail. The vivid dark-gray or brown blotches contrast strongly at first with the paler gray body tones, but as the snake grows the pattern darkens. By the time the snake approaches three feet in length (about two years old) these markings are often lost, and it has assumed the uniform black appearance of the adult black rat snake. The pattern, on close examination, can sometimes still be seen.
The black rat snake frequently is confused with the black racer, but several elements can be used to distinguish between the two. First, the head of the black racer is narrow. The black rat has a squarish head, more broad and with a flattened snout. Second, the scales of the black racer are smooth and unmarked with other colors. The scales on the middle of the back of the black rat snake are slightly keeled, and although its scales seem to be edged in bluish white or yellow, the skin between them is the lighter color.
Range. The black rat snake ranges from southern New England and Ontario south to Georgia, and from Wisconsin to Louisiana. The entire state has some population of black rat snakes, and it is seen quite frequently.
Habitat. The black rat snake occupies a variety of habitats. Anglers, hikers and farmers can expect to see one of these large snakes almost anywhere. It prefers hardwood forests, wooded valleys and hillsides, but the black rat snake might feel just as welcome in an old field, barnyard or active farmland.
Farms might be a favorite because they usually offer a good supply of mice and other small mammals. The black rat snake is an excellent climber and uses small angles protruding from the belly scales to grip the rough bark of a tree. This ability allows easy access to the hollow cavity of an old tree and possible relief from unbearably hot summer temperatures. As winter approaches, the black rat snake seeks shelter underground, sometimes denning with rattlesnakes or copperheads.
Reproduction. The black rat snake locates a suitable mate and breeds in April to June or sometimes not until autumn. By June through August five to 30 eggs are left by the female in decayed logs, piles of leaf litter or under an amply sized rock. The eggs are smooth-shelled and leathery when deposited. They are covered with a moist, glue-like substance that hardens and adheres to the eggs as it dries, becoming slightly yellowish in the process. This causes the eggs themselves to become glued together. The eggs are oblong and 1 1/2 to just over two inches in length. The incubation period takes seven to 15 weeks and ends with the emergence of young black rat snakes 10 to 16 inches long.
Food. The black rat snake hunts on and off the ground because it is capable of climbing with little effort. The young of the species may feed on treefrogs, but also take mice and other small mammals. Birds and their eggs fall prey to the black rat snake, too, so it is evident that not all of its foraging is restricted to ground level.
Eastern Hognose Snake
Heterodon platyrhinos
General characteristics. The hognose snake has been pegged with several formidable-sounding nicknames: puff adder, hissing adder and spreading adder. All arise from a behavior contrived to scare off would-be attackers. When disturbed, the hognose snake widens its neck to take on a hood-like appearance (See Figure VI-17). It does this by flattening the head and neck, spreading long rib bones outward. Then, inflating the body with air, hissing and striking out, the hognose snake suddenly resembles a fearsome-looking creature, but it is harmless.
If awards in various categories were given to snakes, the eastern hognose snake would win hands down for "most dramatic performance." It alternates between playing dead and performing a series of aggressive-looking maneuvers that ultimately prove to be more of a decoy than anything else.
If approached, the hognose snake may attempt to fool the intruder by rolling over and "playing dead." A few convulsive jerks may first set the stage and then with mouth agape and tongue hanging out, the performance ends with the body frozen in place. If picked up, the snake suddenly goes limp. But returned upright to the ground it again quickly rolls over on its back, apparently forgetting it is "dead."
In Pennsylvania, the eastern hognose snake resides in a major portion of the state, although it is not found in abundant numbers. Adult sizes vary from 18 to 45 inches.
Identification. A pointed and slightly upturned snout gives the hognose snake its name. It has a wide neck leading to a stout body. The body color varies and may be yellow, tan, brown, gray or reddish-hued. More or less square blotches appear on the back, alternating on their edges with round dark spots. Some specimens have been observed on which there are no discernible blotches. Instead, they are a uniform black, brown or greenish. The belly is yellow, light gray or pinkish and is mottled with gray or shades of green. The underside of the tail is lighter than the belly. A divided anal plate and scales that are keeled complete the description.
Range. The eastern hognose snake, though limited in numbers, inhabits roughly the eastern two-thirds of the state. Its range arcs from Somerset County in the southwest to Wayne County in the northeast. It also dwells in a portion of the Lake Erie Drainage. Outside of Pennsylvania, its range extends from New England to Florida and west to Minnesota and Texas.
Habitat. The hognose snake likes dry terrain, preferring open areas, thinly wooded uplands or rock-strewn hillsides. Sandy and other dry soil that is easily crumbled attracts the hognose snake, and it occasionally is seen by farmers working their cultivated fields. During the winter months, the hognose snake seeks relief by burrowing deeply into the soil.
Reproduction. Mating can occur in either the spring or fall. The hognose snake lays eggs usually in June or July, but sometimes as late as August. The female deposits from six to 61 eggs in a shallow cavity of loose or sandy soil. Leathery, white and thin-shelled when released, they are about 1 1/4 inches in length and elongated. The eggs swell to become more spherical while increasing in size by about one-third. They hatch in 40 to 65 days, producing youngsters of about six to nine inches in length. The hatchlings display the same markings as the adult hognose snake, but tend to be more gray than yellowish brown.
Food. The eastern hognose snake is most active during the day. That's when it feeds. Toads and frogs are the mainstay of the hognose snake diet, although salamanders may be added. The young hognose snake consumes crickets and other insects.
Eastern Kingsnake
Lampropeltis getulus getulus
General characteristics. Although it has been described as an attractive snake, the eastern kingsnake is one of the least sociable, clashing at times with other snakes. It has been known to wrap itself around copperheads and other snakes to suffocate its victims. The kingsnake is reputedly immune to the venom of pit vipers.
The kingsnake becomes nocturnal during the hottest days of summer, but otherwise it is most active during the daylight hours. It shows a particular preference for moving about in the early morning hours and again toward twilight. The kingsnake is a close relative of the more common milk snake. It is a large snake, reaching adult sizes of three to over six feet. It has been known by several other names, such as thunder snake and chain snake.
Identification. Its nickname "chain snake" is descriptive of the bold yellow or white chain-like pattern that laces the body. This design contrasts sharply with the rest of the body, which is chocolate brown to shiny black. Yellow or white blotches often cover the black belly. The kingsnake's narrow head is marked with yellow-white. The neck is distinct and emphasizes the stout, cylindrical body. Smooth scales cover the body. The anal plate is single.
Range. In Pennsylvania, the eastern kingsnake historically has been recorded from a very limited area, in parts of two counties in the southeast. However, no verified specimens exist from Pennsylvania, and the status of this species as a bona fide member of our snake fauna is still questionable. It is known from southern New Jersey to Florida and west to the Appalachians and southern Alabama.
Habitat. The kingsnake is primarily a terrestrial creature, although it makes its way up the trunks and branches of shrubs and small trees every so often. Its preferred habitat consists of rocky, wooded hillsides, especially those near water. It can be found within swampy areas as well. Stream banks are a favorite haunt because they often are a ready source of turtle eggs and water snakes. The kingsnake is a willing swimmer when the occasion calls for it. Logs, debris and piles of loose rocks offer hiding places for this often secretive reptile.
Reproduction. Seeking and finding a mate from early spring to late June allows the female to deposit from five to more than 20 eggs sometime from June through July. The eggs are leathery and yellowish to creamy white. More or less elongated, the eggs measure 1 1/4 to nearly three inches long. The female coils herself around the eggs perhaps for a day or two and then departs. After incubating eight to 11 weeks, the eggs hatch to produce a miniature version of the parents. The hatchlings measure nine to 12 inches.
Food. The eastern kingsnake is a strong constrictor and uses this physical power to disable its prey. Its menu consists of other snakes including copperheads and rattlesnakes. It is thought immune to the venom of the state's venomous snakes and thus can attack these species with little apparent harm to itself. It also pursues lizards, rodents and birds and their eggs.
Eastern Milk Snake
Lampropeltis triangulum triangulum
General characteristics. In Pennsylvania at least, the eastern milk snake is the subject of more tales and is more often mistakenly identified than any other snake. It is among the state's most beneficial snakes, but sadly, is also the most often killed in mistake for a copperhead. Actually, there is only a superficial resemblance between these two snakes. The head of the copperhead is an easily recognized coppery color without any marks. The head of the milk snake is light with brownish marks. The belly of the copperhead is unmarked and a uniform cream or off-white. The Northern Copperhead belly of the milk snake is white with dark splotches resembling a checkerboard pattern (See Figure
VI-18).
Other snakes confused with the milk snake include the northern water snake with its keeled scales, compared to the milk snake's smooth scales. The northern water snake also has a divided anal plate. The milk snake's anal plate is single. The juvenile northern black racer and black rat snake, which unlike their adult counterparts are patterned, can be told by the anal plate. Both have divided anal plates compared to the single plate of the milk snake.
The milk snake, contrary to popular belief, does not milk cows. Thus, this alleged habit hardly contributed to its name. Rather, the name probably originated from its habit of spending a lot of time around barns, not a bad idea considering its fondness for mice.
The eastern milk snake, although considered to be more secretive than many other snakes, still is seen quite often. It appears in numbers throughout its range. Adults attain lengths of two to over four feet when fully grown.
Identification. The most important identifying characteristic of the eastern milk snake is its belly. The belly is white or cream-colored with dark more or less square splotches that create a checkerboard effect. This definitive pattern separates the milk snake from the copperhead, which has a uniformly colored white to grayish belly with sometimes mottled markings or cloudy blotches (See Figure VI-18). The body of the eastern milk snake is gray or tan. This color is interrupted with chocolate-brown to reddish-brown blotches or saddles that cross over the back and down each side. These darker saddles are bordered with black. They are widest across the back, nearly rectangular but may become narrower as they continue down the sides. This, too, can be used to distinguish the milk snake from the copperhead, which has dark bands that are at their narrowest across the back, wider at the bottom. Smaller, dark blotches also appear low on the side, near the belly. They fall in place between the bottoms of the larger saddles. A Y-shaped or V-shaped dark mark appears on the nape of the neck, extending onto the head. Smooth scales shield the body and the anal plate is single.
Range. You are likely to run into the eastern milk snake nearly anywhere in the state because it is distributed in all 67 counties. It occurs over much of the Northeast, extending well into Canada and west to Minnesota.
Habitat. The milk snake does not prefer any particular type of habitat and is apt to reside in suburban as well as rural areas. Damp bottomland, meadows and farmland harbor the milk snake. But pine forests, open deciduous forests and rocky hillsides also are acceptable to the milk snake in which to make its home and forage for food. Rotting logs and damp trash offer convenient places for the milk snake to take refuge.
Reproduction. Leaving the den during the spring months, the eastern milk snake immediately begins its search for a mate. In June or July, the female deposits from six to 25 or more elliptically shaped eggs, often in a rotted log. The eggs incubate for six to nine weeks, and in August or September the juveniles emerge. Some five to 11 inches long, they are more brightly colored and their patterns more sharply contrasted than their parents.
Food. The eastern milk snake's favorite prey is small rodents, and mice make up the largest portion of this group. Other snakes, including venomous species, also are taken, and lizards and an occasional bird supplement the diet.
Northern Water Snake
Nerodia sipedon sipedon
General characteristics. This is the largest of Pennsylvania's three water snakes, reaching an adult size that may range from 24 to over 50 inches. The male is usually smaller than the female.
Often killed by people out of fear, the northern water snake is not a water moccasin and it is not venomous. The water moccasin, or cottonmouth, common to the South, is not found naturally in Pennsylvania and does not appear farther north than extreme southern Virginia.
The northern water snake has a tendency to display a nasty disposition and becomes quite formidable when angered. It flattens its head and heavy body when striking, and although it flees if it can, it strikes repeatedly if cornered. It has strong jaws, powerful enough to inflict a severe bite. Bites by the northern water snake also may bleed profusely due to an anticoagulant quality of the snake's saliva. It does not inject a poisonous venom.
The northern water snake is active both day and night and appears in sufficient numbers to be seen on a regular basis.
Identification. It is possible to see the northern water snake in an array of colors. On some adults, the patterns may even become obscure, blending into the background color. Generally, the northern water snake is reddish, brown or gray to brownish black. There are dark crossbands on the neck region. These bands become dark blotches, alternating in position from the back to each side as they progress down the body and onto the tail. The dark patterns are wider than the spaces between them. White, yellow or gray covers the belly, which is interspersed with reddish-brown or black crescent-shaped spots. The head of the northern water snake is distinct, well-defined from the neck. Its scales are keeled and it has a divided anal plate.
Range. The northern water snake can be found from Maine, across Quebec, reaching down to Colorado in the west. It extends south to North Carolina. All of the state's 67 counties are host to the northern water snake.
Habitat. Scattered statewide, it is possible to encounter one of these aquatic-loving animals when hiking near a stream or lake, or fishing or boating. It prefers quiet water. Still, the northern water snake is found in fast-moving streams as well as lakes, ponds, bogs and swamps and rivers or slower streams. Submerging, it swims underwater seeking protection among the pondweeds and other aquatic plants. When basking, it likes to drape itself over the branches of a nearby shrub or gather the warmth from a sun-baked rock near the water's edge. It may seek relief from the hottest days of summer by becoming at least partially nocturnal.
Reproduction. As springtime temperatures warm the air, the northern water snake stirs from its winter home in pursuit of its mate. Mating could occur as early as April or as late as June. The northern water snake gives birth to living young. An average litter of 25 young water snakes is produced during the period of August to October. Measuring six to 12 inches at birth, they are a brighter color than the parents.
Food. The northern water snake hunts most of its food in the water. On occasion it leaves the water to search for frogs among the grasses and other vegetation at the water's edge. Salamanders, crayfish and other crustaceans, minnows and slow-swimming, usually sick or disabled fish add variety to the menu of the water snake. Even small mammals have been known to fall prey to this water snake. Rounding out the predator-prey relationship, young northern water snakes are in turn eaten by the larger sport fish.
Rough Green Snake
Opheodrys aestivus
Endangered Species
General characteristics. It is easy to understand why this snake carries the nickname "vine snake," considering its color, slight build and penchant for climbing through brush. The rough green snake is a graceful animal, liquid-like in its movements from one tree branch to another. It is mild-tempered and not easily aroused when confronted. At 22 to 32 inches, it is the largest of the state's two green snakes.
Identification. The rough green snake has a slender body with a long, tapering tail. Its body is a consistent light or pale green throughout except for a white to yellowish-green belly. Its color is uniform throughout, and it has no markings. The divided anal plate is evident, and the scales are sharply keeled, hence its name, the rough green snake.
Range. The rough green snake is found only in two small areas of the state, in each of the southern corners. It extends south to the Florida Keys and west to Kansas and Texas. From here, its range continues into a portion of Mexico. In Pennsylvania, it's a threatened species.
Habitat. It is arboreal because it spends most of its time in brush, trees and vines such as greenbriers. It especially likes dense growth near a stream or lake. It is an excellent climber and it blends well with its background, its green color easily melting into the surrounding foliage. But the rough green snake is also a good swimmer and does not hesitate to glide quickly and silently into the water if disturbed.
Reproduction. The rough green snake locates a suitable mate in spring or fall. It is oviparous, which means that it lays eggs rather than gives birth directly to live young, as do some other snakes. The eggs are deposited in June through August, usually in a depression beneath a well-placed stone or rock. Three to 12 eggs are laid. They are hard and shaped like a capsule about 1 1/2 inches long. They hatch in five to 12 weeks, revealing young grayish-green snakes seven to just under nine inches in length.
Food. The rough green snake forages for food as it moves gracefully through the inner branches of a basket willow or other small tree or shrub. But it seeks prey on the ground as well, moving slowly through the grasses in search of a meal. Crickets, spiders, caterpillars and grasshoppers make up the main diet of the rough green snake.
Eastern Smooth Green Snake
Opheodrys vernalis vernalis
General characteristics. Commonly known as the "green grass snake," the eastern smooth green snake spends most of its time on the ground. It is the terrestrial cousin of the arboreal rough green snake and is slightly smaller. Adult sizes range from 14 to 20 inches. It is said to be the most gentle of all North American snakes.
Identification. The eastern smooth green snake is small and streamlined in appearance with the body ending in a long, tapered tail. Its body is a bright grass-green above with a plain white belly tinged with just a touch of pale yellow. The anal plate is divided and the smooth scales (keeled scales on the rough green snake) depict the name of the eastern smooth green snake.
Range. From Pennsylvania, the range of this snake extends south through parts of Virginia and West Virginia and north to Canada's Maritime Provinces. Minnesota marks its western boundary. Unlike the rough green snake, the eastern smooth green snake is distributed almost entirely statewide. The only exceptions may be the two small locations where the rough green snake resides.
Habitat. The eastern smooth green snake is largely terrestrial, spending more time on the ground than above it. It can be found in meadows, grassy marshlands, moist, grassy fields and even along the edges of forests. Hikers and others might encounter the eastern smooth green snake because it is most active during the day. A good eye may be necessary, however, because the color and build of the eastern smooth green snake provide excellent camouflage in its grassy domain.
Reproduction. Waiting for the sun to move a bit more northward, the eastern smooth green snake is one of the last to emerge from winter's hibernation. Mating occurs in spring to late summer. Three to about 10 eggs are laid in July to August under a sun-warmed stone, which helps them incubate. Thin-shelled and cylindrical, the eggs hatch in four to 23 days. The snakes that emerge are four to six inches long and dark olive-gray. It is not unusual to find several females sharing the same nesting area.
Food. The eastern smooth green snake is unusually insectivorous, feeding on a variety of insects and larvae. People should consider the eastern smooth green snake a good friend, given its partiality for insects.
Queen Snake
Regina septemvittata
General characteristics. Another of Pennsylvania's snakes categorized as "water" snakes, the queen snake in some local areas may be known as the "willow" snake or "leather" snake. It is very much an aquatic animal and an excellent swimmer. If disturbed by an intruder it does not hesitate to slip quickly into the water for safety. Adult queen snakes are 15 to 36 inches in length.
Identification. The queen snake is an attractive snake and a study in contrasts. The body color can be tan to shades of brown or almost black. A yellow stripe accents the lower side of the body and the belly is yellow with four well-defined brown stripes running its length. Two of these stripes are located near the center. Two larger stripes stretch along the sides of the belly. Some specimens may also have three faded stripes continuing down the back. The scales are keeled and the anal plate is divided.
Range. In Pennsylvania, the queen snake is found in about the western third of the state between the northern and southern borders. The range then splits, jumping the Allegheny Mountains to appear in the southeastern corner, where it extends as far west as Franklin County. Its range takes it to the Gulf Coast. It also is found in the Great Lakes region.
Habitat. The queen snake prefers streams and small rivers as opposed to lakes or ponds, with a preference for those waterways amply strewn with rocks along their bottoms and sides. It does not emerge to bask as much as other water snakes. More often it can be seen swimming along the surface of the moving water or found under shoreline rocks.
Reproduction. The queen snake selects its mate in April or May. The eggs develop internally and the female gives birth to her young in late August to early September. The young may number from five to just over 20 individuals. The newborns range from 7 1/2 to about nine inches in length. They look much like the adult queen snake except that the belly stripes tend to be more clearly defined.
Food. The queen snake has a definite preference when it comes to finding a meal. Considering its aquatic habitat, it's no surprise that the queen snake feeds almost exclusively on crayfish and especially those in the soft-shelled stage.
Northern Brown Snake
Storeria dekayi dekayi
General characteristics. Every so often someone might refer to the northern brown snake as "Dekay's" snake, referring to James Edward Dekay, an early New York zoologist for whom this reptile was named.
Like so many other snakes, the northern brown snake is secretive, preferring to keep its whereabouts unknown. It is also one of the state's smallest snakes, reaching adult sizes of only nine to 13 inches. For the most part, the northern brown snake is most active during the day. However, when warm weather sets in, it becomes more nocturnal, choosing to roam over its somewhat limited range after the sun has set.
Identification. The northern brown snake is a small snake but with almost disproportionately large eyes. Its back and sides range in color from gray to yellowish brown, brown or reddish-brown. It has two parallel rows of small dark spots bordering a wide but indistinct stripe that runs down the center of the back for its full length. The belly can be pale yellow or brown, even pinkish, and it is edged with small black spots. In some specimens, a dark bar extends from just behind the eye downward to the upper lip. The scales of the northern brown snake are keeled and the anal plate is divided.
Range. The northern brown snake is abundant in a major portion of the state, and although this snake is thought to be distributed statewide, that may not be the case. Reported sightings are absent in the northern half of the state east of the Allegheny Mountains. Its natural range begins in Maine and continues south to Virginia.
Habitat. The northern brown snake is usually found near water or areas that remain damp most of the time, settling into moist upland woodland or lowland marshes. Margins of swamps or bogs are acceptable habitat and it has showed up in gardens, even golf courses, parks and other urban environs. Wherever it resides, the northern brown snake takes refuge under downed logs, flat rocks and even trash, if need be.
Reproduction. Mating in either the spring or autumn, the northern brown snake gives birth to three to 30 live young in July through September. Barely three inches to perhaps nearly five inches long at birth, the young Dekay's snake is only a sixteenth of an inch in diameter. The newborn is a bit darker than its parent and has a yellowish collar across the neck. It assumes the adult colors during its first summer.
Food. Food consists mainly of worms, slugs and snails, prey that is usually easy to find in a damp environment. Not much else is consumed by the northern brown snake, which in turn is preyed on by skunks, hawks and owls.
Northern Redbelly Snake
Storeria occipitomaculata occipitomaculata
General characteristics. A snake of small proportions, the northern redbelly snake rarely exceeds eight to 10 inches. It is secretive and often goes undetected by anglers and others who regularly spend time outdoors.
Identification. The northern redbelly snake may be gray, black, brown or rusty red with stripes that vary in number. A single broad, light stripe may run down the back. Four faint, narrow, darker stripes may be present. In some cases, all five stripes appear. The head has a blackish cast over the body color, and there are three distinct light spots on the nape of the neck. The belly, reddish in most cases, also may be orange or yellow or even blue-black. The belly is unmarked and can be distinguished from Kirtland's snake, which has a double row of black spots down the belly. The scales are keeled and the anal plate is divided.
Range. The northern redbelly snake is most common in the northern tier counties and in other mountainous regions of the state. It is found to a lesser extent west of the Allegheny Mountains. Except for Florida, it is found over nearly the eastern half of the United States. It extends into parts of Canada.
Habitat. The northern redbelly snake likes forested areas, residing in densely covered mountains or hilly woodland. It is also known to dwell in bogs, apparently content in habitat that may range from quite wet to only slightly moist. It hides under a variety of debris and could be found in seclusion among lumber, stone and other objects piled around houses.
Reproduction. The northern redbelly snake comes out of its hiding place during the spring or fall in search of a mate. After breeding, from one to 20 young are born in early June to September. When born, the young redbelly snakes measure from just under three inches to about four inches in length. They mature in two years. The young reptiles resemble their parents in appearance, although the juveniles may be a bit darker, and show more contrast in the pattern.
Food. The northern redbelly snake prefers to feed on slugs and worms.
Shorthead Garter Snake
Thamnophis brachystoma
General characteristics. There are three garter snakes that make Pennsylvania their home, the eastern garter snake, the shorthead garter snake and the ribbon snake. The shorthead garter snake, at 14 to 18 inches, averages a bit smaller in size than the eastern garter snake and is not as widely distributed. Still, the shorthead garter snake is quite common in its range. It congregates in large colonies.
Identification. Taking a clue from its name, one could correctly assume that the head is short. Most people would find it difficult to distinguish where the neck ends and the head begins because both are the same diameter. The shorthead garter snake is blackish to dark shades of brown, accented with a well-defined light brownish or tan stripe down the middle of the back and a stripe along each side near the belly. At times, these side stripes are bordered by narrow black lines. The rows of black spots that occur between the stripes on other garter snakes are absent on the shorthead garter snake. The scales are keeled and the anal plate is single.
Range. Northwestern Pennsylvania is included in the original range of the shorthead garter snake. It extends into only a small portion of southwestern New York.
Habitat. It is found in the uplands, preferring old fields, meadows and pastures. The shorthead garter avoids woodlands, which its cousin the eastern garter snake will not. It takes shelter in piles of stone and under other debris in open areas, often near water.
Reproduction. The shorthead garter snake seeks its mate in March or April. By late July through September, the female gives birth directly (it does not lay eggs) to five to 15 juveniles. Five to six inches long at birth, they're already one-third their adult size.
Food. Worms make up the primary diet of the shorthead garter snake. Insects and small amphibians round out the menu.
Ribbon Snake
Thamnophis sauritus
General characteristics. This animal is a close relative of the eastern garter snake and shorthead garter snake, but it is considered more aquatic. It attains a size equal to its cousin, the eastern garter snake, roughly 18 to 26 inches. Very agile, the ribbon snake moves quickly and with little effort through thick vegetation. In the water, the ribbon snake glides swiftly across the surface. It rarely dives in the manner of true water snakes. Two subspecies are found in Pennsylvania. The eastern ribbon snake (Thamnophis s. sauritus) and the northern ribbon snake (Thamnophis s. septentrionalis).
Identification. This snake is slender, with fluid lines and a tail that is quite long. Three bright-yellow stripes, one on the back and one on each side, contrast sharply with a dark body that is reddish brown on the northern ribbon snake and black on the eastern ribbon snake. A dark-brownish stripe marks the margin of the belly. The belly itself is yellowish or greenish and has no markings. There appears just a touch of yellow under each eye. Close examination reveals keeled scales and a single anal plate.
Range. The ribbon snake can be found within a split range in Pennsylvania. The northern ribbon snake resides in the northwestern part of the state. The eastern ribbon snake is found in the balance of the range. Appearing west and east of the Allegheny Mountains, this colorful creature has not populated the mountains or plateaus themselves. It extends south into Georgia and the Gulf Coast.
Habitat. It is at least semi-aquatic, so one could expect to find the ribbon snake in wet meadows, bogs and marshes. It likes the weedy shorelines of lakes and shallow, meandering streams. It normally avoids deep water. It often suns itself draped on the branches of overhanging shrubs or trees. From here it can drop quickly to the water if startled. The ribbon snake seldom wanders far from its watery environs.
Reproduction. Soon after emerging from hibernation in the spring, male ribbon snakes begin looking for a suitable mate. The young are born by late summer, usually July through August. The litter can include anywhere from three to 25 juveniles. They measure seven to nine inches at birth and mature within two to three years.
Food. It should be expected that the ribbon snake would eat animals sharing its aquatic-related habitat. Thus, frogs, salamanders and small fish are the main staple of its diet. Interestingly, the ribbon snake normally does not consume earthworms, a favorite of others of the garter snake group.
Eastern Garter Snake
Thamnopnis sirtalis sirtalis
General characteristics. The chances are very good that anyone who has spent any time at all outdoors has seen an eastern garter snake at least once. It is the most widely distributed and familiar snake in North America. Adults attain lengths of 18 to 26 inches, a bit larger than the shorthead garter snake, but about equal to the ribbon snake, a close cousin.
Doing most of its traveling and foraging during the day, the eastern garter snake is active over a longer period than most other snakes. Able to tolerate colder temperatures, it leaves the den first in the spring and it's the last to hibernate in the fall.
A built-in defensive mechanism consisting of musk glands may cause potential attackers to have second thoughts. Discharge of a repugnant odor from the gland located in the vent would repel all but the most determined. The garter snake also may assume a defensive posture by flattening its body, hugging itself against the ground as do the water snakes, to which it is related.
Identification. The eastern garter snake is dark greenish to black across the body. Stripes, normally three, trail down the back and sides. They can be yellowish to brown or greenish, but regardless, usually are well-defined. A double row of spots commonly appears between the stripes. The belly of the eastern garter snake varies from greenish to shades of yellow and includes two rows of indistinct black spots. Like the shorthead garter snake, the eastern garter snake displays keeled scales and a single anal plate.
Range. The eastern garter snake appears over a wide range. It is found from Florida and the Gulf Coast north to well inside Canada. It goes as far west as eastern Texas and Minnesota. A statewide resident, the eastern garter snake has been found in all of Pennsylvania's 67 counties.
Habitat. This snake is often seen near water, where it locates some of its favorite food. The eastern garter snake also likes wet meadows, marshes and damp woodlands. It is a frequent visitor to farms and parks where it might be seen hunting food in the midst of moist vegetation. Even an urban area, especially where moisture or damp ground is found, could be a host to this well-known reptile.
Reproduction. The eastern garter snake mates sooner than most other snakes, beginning as early as late March and in some cases continuing into early May. In some instances, it may even mate in the fall. Mating occurs at or near the den where the winter was spent in hibernation. The male searches for a suitable mate using sensory organs located in small tubercles on the chin. The progeny are born alive from late June to August and could number from as few as seven to as many as 85. In many cases, however, only a few survive. Those that do make it through the early weeks mature in about two years and are ready to mate by their third spring. The young garter snake is five to nine inches long at birth. It subsists on earthworms almost exclusively until its first hibernation.
Food. Even as an adult, the principle food of the eastern garter snake is earthworms. But after emerging from the den its first year it begins to take other food as well. Frogs, toads and salamanders add variety to the diet, as do insects, small mice and an occasional bird.
Smooth Earth Snake
Virginia valeriae
General characteristics. At a maximum seven to 10 inches long, the smooth earth snake competes with the eastern worm snake for the "smallest snake in the state" title. In fact, a subspecies is often seen in southeastern Pennsylvania with the worm snake with which it shares similar habitat. A good time to look for the smooth earth snake is immediately after a rainfall. It seems to enjoy a moist if not wet environment. The smooth earth snake is represented in Pennsylvania by two of three subspecies, the mountain earth snake (Virginia valeriae pulchra) and the eastern earth snake (Virginia v. valeriae).
Identification. The smooth earth snake is reddish brown to gray and has no distinctive markings other than possibly widely scattered small dark flecks over the body; on the eastern earth snake, flecks appear in rows on the back. The belly is unmarked and can be grayish, off-white or yellowish. On occasional specimens there may be a dark area between the eye and nostril. The scales are smooth on the eastern earth snake and very slightly keeled on the mountain earth snake. The anal plate is divided.
Range. In Pennsylvania, the mountain smooth earth snake is distributed along the Allegheny Mountains, beginning in Somerset and Fayette counties. Its range branches out in a funnel-shaped pattern as it goes northward. It extends south into West Virginia. The eastern earth snake appears in the extreme southeastern corner of the state, where its range extends south to Georgia and to the Gulf Coast.
Habitat. Like the worm snake, the smooth earth snake prefers damp areas, especially when associated with a deciduous forest. It also is found in abandoned fields, as well as moist hillsides covered with rocks and timber.
Reproduction. The young of the species are born in August or September, with two to 14 unmarked reptiles included in the litter. They are three to slightly over four inches long at birth. Highly secretive, the smooth earth snake stays underground for long periods, emerging after a cool, heavy rain. Hiding under rocks or stones warmed by the sun is another favorite retreat.
Food. The diet of the smooth earth snake consists of earthworms, soft-bodied insects and their larvae.
Northern Copperhead
Agkistrodon contortrix mokasen
General characteristics. One of only three venomous snakes common to Pennsylvania, the northern copperhead is a close cousin of the cottonmouth or water moccasin found in more southerly aquatic environments. Reflecting its preferred habitat, the copperhead sometimes is referred to as the "upland" or "highland" moccasin. However, the cottonmouth is not indigenous to Pennsylvania.
The copperhead is a quiet creature—some would say almost lethargic—and usually does its best to avoid trouble, quietly stealing to a safe retreat whenever it can. If threatened, and it feels the need to protect itself, the copperhead is capable of striking out most vigorously. If the strike hits its intended victim, poison may be injected through two hollow fangs connected to glands located on each side and toward the rear of the head (See Figure VI-15). The venom-injecting apparatus is similar to that found in the rattlesnake, although the copperhead's fangs tend to be a bit shorter. The venom is a hemotoxin, but with a trace of neurotoxin and as such primarily affects the bloodstream. The bite and resultant injection of venom is painful. But with prompt medical attention, it seldom poses any serious threat to life.
Identification. The copperhead, reaching an average adult size of 24 to 36 inches, is a stout-bodied snake, perhaps heavier than most harmless snakes of a similar length. The body color is copper or hazel-brown, sometimes accented with a tinge of pink or orange. Bold chestnut or reddish-brown crossbands are narrowest across the midline of the back and wider at the sides. They present the appearance of a dark hourglass if one imagines them stretched out flat. There may be small, dark spots between these bands. The crossband patterns on the copperhead are dark, but on the milk snake, a snake often confused with the copperhead, the hourglass-shaped cross-bands are a lighter color. Thus, the dark pattern on the milk snake is at its widest across the midline of the back, compared to the narrower dark band on the midline of the copperhead.
The belly of the copperhead is a mottled pattern of white to gray. This feature also can be used as an aid in separating the copperhead from the milk snake, which has a black and white belly pattern roughly resembling a checkerboard (See Figure VI-18). The unmarked head, somewhat triangular, is covered with large copper-colored scales.
The pupil of the eye is vertically elliptical (similar to a cat's pupil). It is a feature that can be used to distinguish all of Pennsylvania's venomous from its non-venomous snakes (See Figure VI-14). The pupil is rounded on the non-venomous snakes common to Pennsylvania. The copperhead also has the facial pit located between the eye and nostril, common to Pennsylvania's three venomous snakes. This heat-sensitive organ is missing from the non-venomous species in Pennsylvania (See Figure VI-14).
The scales on the copperhead are only weakly keeled. The anal plate is single and the scales on the underside of the tail are in single rows for most of its length, not divided into two rows as they are on the non-venomous snakes in Pennsylvania.
Range. The copperhead inhabits the lower two-thirds of the state. Its range generally follows the southern limits of huge glaciers that eons ago scraped and ground their way into the northern hemisphere. Its range extends somewhat southwesterly through the Carolinas into Georgia, Tennessee, Kentucky and southern Illinois.
Habitat. The northern copperhead likes wooded hillsides, especially those that feature rocky outcrops standing guard above a stream or swampy area. The copperhead is attracted to stone walls, piles of rock and other similar debris and is a frequent visitor around farms and abandoned lumber operations. It is fond of curling up in sawdust or rotting logs, and it likes the protection offered by large, flat stones, especially those located near water.
The copperhead, like so many other reptiles and amphibians, enjoys a day in the sun and often basks on a favorite rock, especially on a warm day in the spring or fall. During the hotter days of summer, the copperhead seeks relief from the piercing rays of the sun and becomes more nocturnal in its habits.
Reproduction. Recent studies indicate that the mating period for the copperhead can be anytime from spring to autumn, with the peak time probably mid-summer. One to 14 live young are born in August to early October. Seven to 10 inches long at birth, the young copperhead matures in two to three years. The young snakes learn early in life to fend for themselves by using the tip of their tail as a built-in lure. Usually bright yellow, the tail tip is held upright. Wriggled enticingly, it attracts curious prey to a hungry youngster. By the time it is one hour old, the juvenile copperhead has venom strong enough to paralyze a mouse.
Food. A young copperhead's first food is normally insects, but it soon seeks rodents, the main staple of its diet. Birds, cicadas when available, large caterpillars and an occasional frog or lizard help diversify the menu.
Timber Rattlesnake
Crotalus horridus
Candidate Species
General characteristics. Though not the largest snake found in Pennsylvania, the timber rattlesnake has the distinction of being the largest of our three venomous species. It may reach adult sizes of 36 to 54 inches. It is sometimes called the "banded" rattlesnake or "velvet-tail" rattler.
Like the copperhead and other snakes, the timber rattlesnake would just as soon be left alone. It is not an aggressive creature. The timber rattler is prone to lie quietly or crawl away to safety if given the chance.
The timber rattler stands its ground (like many other animals) if it feels threatened and unable to escape. When striking, venom may be released from glands located in the head and injected into the victim through modified front teeth referred to as fangs. It should be noted that a defensive strike does not always include a release of venom. Venom primarily is used to disable prey.
Contrary to popular belief, the timber rattlesnake does not always sound its familiar alarm before striking. In fact, when striking because of fear or the need to defend itself, more often than not the snake strikes without an audible warning. The "rattle," from which this snake obviously gets its name, is an organ of loosely attached, hollow horny segments fastened to the tail. Rapidly vibrating the tail causes these button-like segments to strike one another, producing an unmistakable buzzing sound. The rattle may grow by two to four segments annually, because new segments are added each time the skin is shed. Thus, the number of segments on the rattle, or "cloche," as it is called, cannot be used to determine the age of the snake. However, the larger the snake, the louder the buzzing.
Identification. Timber rattlesnakes are found in two different color phases, black and the less common yellow phase. Each phase is permanent. Coloration does not change from one phase to the other on any individual snake. On a yellow specimen, black or dark-brown crossbands contrast against a yellow background that might range from dull to a deep lemon. In some cases, the "yellow" tends to be brownish or grayish, but always lighter than the black phase. The crossbands are often V-shaped and tend to break up toward the rear of the body to form a row of dark spots down the back and along each side.
The more common black phase timber rattlers have a heavy stipling or flecking of very dark browns or blacks that covers most of the lighter or yellowish pigments. Completely black specimens are not all that rare in some areas.
The unmarked head of the timber rattlesnake is covered with numerous small, keeled scales. The facial pit is located as usual between the eye and nostril, confirming the timber rattlesnake to be one of the pit vipers (See Figure VI-14). The pupil of the eye is elliptical, not rounded as it is on Pennsylvania's non-venomous snakes (See Figure VI-14). The tail is black regardless of the color phase of the body. Unlike our non-venomous species, which have two rows of scales on the underside of the tail, the venomous snakes have one row. The timber rattlesnake is no exception to this rule.
Range. The range of this reptile begins in the north in New Hampshire, extending southward to Georgia. It appears from Illinois to Arkansas and northeast Texas. The timber rattlesnake is found in the central two-thirds of Pennsylvania. Its range does not extend into the counties bordering Ohio or into the extreme southeast. The range follows roughly the major mountain ranges that move diagonally across the state.
Habitat. This snake is at home in timber-covered terrain, especially that of second-growth woodland where an abundance of rodents may be found. It likes wooded hillsides accented with rock outcrops where ledges of stone might provide opportunities for basking (See Figure VI-20). When winter sets in, fissures in these places provide passage to deep dens for hibernation. Slopes with a southern exposure are preferred.
The timber rattlesnake seeks winter protection below the frost line, preferably in dens that maintain a temperature of around 50 degrees. In the spring, as daytime temperatures approach 60 degrees, the rattlers begin to emerge to bask near the den site. Although later they may travel some distance from the den to take up residence in more open areas, shaded areas will always be nearby to provide protection as summer temperatures turn hot. Each fall the timber rattlesnake returns to its original den, even though it may have wandered several miles during the summer months.
Basking in the warm rays of Figure VI-20 the sun is an important and necessary function. By causing the body temperature to increase, the snake ensures proper functioning of several organs while ridding the body of disease and parasites. The female's basking also allows for full, proper development of eggs and embryos.
Reproduction. Breeding takes place in July, August or September with the female giving birth to live young in August or September of the following year. Five to 17 young are born, reaching 10 to 13 inches in length. The brood may include individuals of both yellow and black color phases.
The female matures in four to five years and breeds for the first time at five or six years of age. The female breeds only every two to three years and thus may bear a litter perhaps 10 to 15 times in her lifespan of 30 to 50 years. The intervening years are needed to store sufficient body fat to sustain her during the second summer the progeny are developing. It is believed she does not feed during the summer of her year-long gestation period. While carrying her young, she consumes only rainfall, gathering the precious liquid from small deposits caught by leaves or depressions in rocks. Decreasing populations have made it a candidate species.
Food. Mice and other rodents make up the majority of the food eaten by the timber rattlesnake. Squirrels, rabbits, chipmunks and even small birds add variety to the diet, as do frogs or lizards on rare occasions. The prey is captured as it wanders into striking range of the hunter, coiled and ready and usually hidden near a log or other object. Venom injected into the prey becomes an effective tool in satisfying the need for food.
Eastern Massasauga
Sistrurus catenatus catenatus
Endangered Species
General characteristics. The eastern massasauga is a rattlesnake. It is the smallest of Pennsylvania's three venomous snakes, but the one with the biggest problem. Reflecting concern for its dwindling numbers, this reptile has been placed on Pennsylvania's List of Endangered Species. It is illegal to possess, kill, sell or offer for sale this or any other animal on the endangered list.
The biggest problem facing this small rattlesnake is loss of habitat. A resident of swampy areas, much of its habitat has been drained or dried up. In some cases, new or widened highways encroached into its wet domain and with each new lane of traffic, acres of vital habitat were lost. Its common name, massasauga, is said to be derived from a Chippewa Indian word meaning great river mouth. It alludes to what was typical Chippewa country, which often included swampland surrounding the mouths of rivers.
Identification. Reflecting its preferred habitat, the massasauga rattlesnake sometimes is referred to as the "swamp" rattler. It does not grow much larger than 20 to 30 inches.
The massasauga is brownish gray to almost black on its back and sides with a row of rounded, dark-brown or black blotches running down the middle of the back. Usually three rows of smaller and lighter blotches or spots stretch along each side. A dark bar, bordered with a lighter color, extends from the eye to the rear of the jaw, and several dark bars start at the top of the head and flow onto the neck. The facial pit is in its usual position between the eye and nostril. The belly is black with scattered white or yellowish markings. Nine plates (actually large scales) cover the crown of the head, compared to the timber rattlesnake's numerous small scales. The tail is stocky or stout, ending in a moderately developed rattle. The underside of the tail has a single row of scales, similar to the other venomous snakes in Pennsylvania. The anal plate is single; the scales over the back are keeled.
Range. In Pennsylvania, the eastern massasauga is found in portions of only five or six counties in the westcentral section of the state. It extends into Ohio and as far as Illinois and Iowa. It runs northward to Wisconsin and Michigan.
Habitat. It shows a distinct preference for marshy areas with swampland, flood plains and other wet areas adjacent to drier old-field uplands providing favorite haunts. Even so, there are occasions when the massasauga may stray from these areas and be found in dry woodlands.
Typical of most cold-blooded animals, the massasauga suns itself on mild days, allowing the warming rays of the sun to raise the body temperature to levels beneficial to its functioning. During the hottest part of the summer, the massasauga becomes crepuscular, taking advantage of the cooler twilight hours to roam and feed.
Reproduction. The massasauga breeds primarily during July and August, giving birth to its young between July and early September. A typical litter contains two to nearly 20 youngsters measuring six to nine inches long. At birth, these young rattlers are well-patterned, although a bit paler than the adults. The juveniles have an unmistakable yellowish tail tip.
Food. As might be expected, given its favorite habitat, frogs and other amphibians top the massasauga's menu. Although amphibians may be preferred, lizards, small rodents and small birds are taken from time to time as well. This rattler uses much the same method as that used by the timber rattlesnake in capturing its prey. Venom is injected to immobilize the prey before it is swallowed. The only difference is that the venom produced by the massasauga is not quite as toxic as the venom of its larger cousin.