Snakes

Garter Snake

Figure 1: Photo Credit - Jonathan Mays

Overview

Snakes are among the most misunderstood of all animals. As a result, many beneficial and harmless snakes have met untimely deaths at the hands of shovel-wielding humans. Of the nine species currently found in Maine (Table 1), none is capable of inflicting a venomous bite. Nevertheless, even a non-venomous snake will act aggressively when threatened, often striking at its aggressor, rattling its tail, and flattening out its head.

Observe snakes, like all wild animals, from a respectful distance. Don't attempt to capture them or keep wild snakes as pets. Leave snakes alone. Never kill a snake.

Snakes are an important part of the natural food web; they eat rodents, birds, frogs, insects, and on occasion other snakes. (In turn, a variety of other animals prey on snakes.) Besides their ecological value, snakes offer the careful wildlife viewer a chance to watch one of nature's most efficient predators.

The common garter snake, the most wide-ranging reptile in North America, is also the most abundant snake in Maine. You can find garter snakes from coastal islands to the mountains to your garden; the snakes usually stay close to water or wet meadows.

Snakes in Maine

In Maine, five species of snakes are keeled, that is, they have a keel or ridge running along the midline of each scale from front to back, making the scales appear rough. These five species also bear live young from eggs retained in the body until hatching.

Northern Black Racer

  • Back glossy black, belly gray
  • Found in open, early successional habitats such as grasslands, shrub lands and reverting agricultural areas
  • Eats amphibians, small birds, small mammals, insects and other snakes

Ring-necked Snake

  • Yellow, gold or orange neck ring; gray, brown, black back; yellow belly
  • Found in woodlands
  • Eats amphibians, insects, worms and small snakes

Ribbon Snake

  • Similar in appearance to garter snake
  • Found in semiaquatic habitats
  • Eats primarily amphibians

Brown Snake

  • Brown with rows of black spots on back, dark diagonal streak behind eyes
  • Found in rural areas and mixed forest, both wet and dry
  • Eats primarily earthworms and slugs

Common Snakes in Maine

Common Garter Snake

  • Most common snake in Maine and extremely variable in coloration
  • Habitat generalist
  • Eats earthworms, amphibians, insects, rodents, and occasionally nesting birds

The common garter snake (Thamnophis sirtalis, Fig. 1) is found from coastal islands to mountain regions. This species is easily the most frequently encountered snake in Maine. It can be quite variable in appearance, including individuals with brightly colored yellow, green and blue stripes that run lengthwise along its body and a grayish-blue underside to checkered varieties, to darker and more solid-colored animals with limited pattern. Most grow to two or three feet.

Small garter snakes eat earthworms and slugs. Larger snakes add amphibians, small rodents, nestling birds and fish to their diet.

Garter snakes can survive in suburbia and towns because of their generalist diet and ability to "live" birth (i.e., they do not require a safe place to lay their eggs).

These snakes get their name from their supposed resemblance to the garters that men once wore to hold up their socks.

When disturbed, garter snakes will try to escape, but if threatened they may strike, bite, and smear musk (foul-smelling anal secretions) on their captor. A bite from one of these non-venomous snakes may be alarming, but will rarely break the skin.

Northern Water Snake

Figure 2: Photo Credit - Jonathan Mays

Northern Water Snake

  • Dark brown to gray with reddish brown/black blotches along back
  • Found in aquatic and semiaquatic habitats
  • Eats primarily fish

The northern water snake (Nerodia sipedon sipedon), Maine's most aquatic snake, is found only in the southern half of the state. It prefers slow-moving waters of bogs, swamps, cat-tail marshes and wet meadows. It usually grows to between 24 and 42 inches and is a very robust snake. It is known to defend itself aggressively and can deliver a painful but non-venomous bite.

Northern water snake. The keels – tiny ridges on the scales – break up reflected light; the snake's skin does not appear shiny. (Fig. 2)

Red-bellied Snake

Red-bellied snake (Fig. 3): Photo Credit - Jonathan Mays

Red-bellied Snake

  • Belly red to orange
  • Found in woodlands, along shorelines
  • Eats slugs, earthworms and insects with soft bodies

The red-bellied snake (Storeiria occipitomaculata) can be found in all but the northernmost regions of Maine. Only eight to 12 inches in length, this snake does not bite when handled. It eats a lot of slugs, so is a wonderful snake to host in your garden.

Smooth Green Snake

Figure 4: Photo Credit - Jonathan Mays

Smooth Green Snake

  • Back grass green, underside pale yellow or white
  • Found in upland meadows, open areas, open woods, gardens
  • Eats primarily insects

Often called the grass snake, the smooth green snake (Liochlorophis vernalis), is, as its name suggests, a lovely green color, perfectly camouflaged in its primary habitats of upland meadows, lawns and gardens. This species turns an iridescent blue post-mortem. Found primarily in the southern and central regions of Maine, this snake's diet is largely caterpillars, crickets, grasshoppers and ants. Like the red-bellied snake, smooth green snakes rarely bite.

Smooth green snake. The scales on this species do not have keels, so they reflect light and make the skin appear glossy. (Fig. 4)

Milk Snake

Figure 5a: Photo Credit - Jonathan Mays

Milk Snake

Figure 5b: Photo Credit - Jonathan Mays

Milk Snake

  • Gray/tan with brown or reddish-brown blotches
  • Found in mixed farmlands; dry, open woodlands; sometimes near human dwellings
  • Eats rodents, birds, eggs, other snakes and amphibians

Due to its coloration and habit of shaking its tail when threatened, the milk snake (Lampropeltis triangulum) is sometimes confused with the timber rattlesnake (Crotalus horridus), which has been extirpated from Maine. Milk snakes are strongly marked with brown or reddish blotches and can grow to more than three feet in length. They prefer mixed farmlands and dry, open woodlands and often venture near human dwellings. They prey on rodents, birds, eggs, other snakes and amphibians.

Eastern milk snake adult (Fig. 5a) and juvenile (Fig. 5b).

Note: Four species of snakes do not have keels on the scales. Instead, the scales are smooth and their surface appears glossy. These snakes lay their eggs in well-drained, protected areas.

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Facts about Snakes

Food and Feeding Behavior

  • Snakes are predators and eat many animals thought to be pests, such as mice, voles, snails and slugs. Other prey items include insects, birds and their eggs, fish and frogs.
  • Snakes have hinged jaws that allow them to consume food that is wider than their bodies. Even so, what a snake eats depends on its size; generally, larger snakes eat larger food items.
  • Snakes have forked tongues that deposit air molecules on receptors in the mouth; thus, snakes "taste" the air, which helps them locate prey and sense their way in the dark.
  • Snakes store food as fat and can live off their fat reserve for extended periods of time.

Shelter and Hibernation Sites

  • From spring to fall, snakes use rodent burrows, spaces under logs and tree stumps, rock crevices, and lumber and rock piles as dens for shelter.
  • Snakes in Maine use these dens to hibernate during winter, either alone or in a group site called a hibernaculum. The hibernaculum must be adequately vented, neither too dry nor too wet, and warm enough to prevent death by freezing.
  • Snakes will use the same hibernaculum year after year; multiple snakes of different species may occupy the same hibernaculum.
  • Emergence from hibernation can begin as early as March, depending on the species, location and snow cover. Snakes may temporarily emerge from hibernation to feed and bask during warm periods in mild areas.

Reproduction

  • For most species, courtship and mating occurs shortly after snakes emerge from hibernation.
  • The garter snake, brown snake, red-bellied snake, ribbon snake and northern water snake bear live young from eggs retained in the body until hatching.
  • All other Maine snakes – the northern black racer, ring-necked snake, milk snake and smooth green snake – lay eggs in well-drained, protected areas that receive enough external heat to hatch.
  • Young are born from July through September and fend for themselves after hatching.
  • Young snakes grow rapidly, and reach sexual maturity in two or three years.

Mortality and Longevity

  • Coyotes, foxes, opossums, raccoons, skunks, weasels, great blue herons, hawks, eagles and owls all prey on snakes.
  • Humans, domestic cats and dogs, lawn mowers, weed-whackers, and vehicles fatally wound or kill snakes.
  • Additional mortality may be caused from snakes becoming entwined in erosional/vegetative netting or becoming trapped in deep storm-water culverts.
  • Garter snakes have lived as long as 18 years in captivity. This age might be exceptional for a wild snake, but little is known on this subject.

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Viewing Snakes

All snakes tend to be inconspicuous, preferring to move away and hide or lie still in the hope of being overlooked. Most encounters are momentary. Although snakes are often seen as threatening, they hiss, strike or bite only if cornered or restrained.

Most of the time, snakes are slow moving, but they can make short dashes to chase prey or escape from predators.

Because snakes are particularly active and less wary during the breeding season, spring is a good time to be on the lookout for them.

Snakes are often inactive during the hottest part of the day, especially in mid- to late summer, and seek shelter or crawl underground to avoid overheating. Snakes may become more active at night when the air cools but the ground remains warm.

It is environmentally unsound to capture snakes and try to relocate them on your property or keep them as pets. Due to their well-developed homing instincts, most snakes will soon leave an unfamiliar area; predators or cars often kill them as they try to return to home ground.

Basking Sites

Most snakes reach their preferred body temperature by basking on surfaces exposed to sun. They control their body temperature by moving in and out of the sunlight, and by changing their orientation to it (facing the sun, back to the sun, etc.). They also derive body heat by lying on or under warm surfaces.

Snake Tracks

Figure 6: Drawing Credit Kim A. Cabrera

In hot areas, look for snakes basking in the morning sun on asphalt, concrete, rocks and wooden fences. In cooler regions, watch for them throughout the day. Snakes tend to bask on sun-warmed roads in the evening, a behavior that often leads to their death.

Tracks

You can most easily find snake "tracks" in sandy or dusty areas in their preferred habitats. These marks may be wavy or straight lines (Fig. 6). Surface material is usually pushed up at the outside of each curve.

Snake "tracks" are sometimes characterized by side-to-side undulations. The distance from one curve to the next varies according to the age of the snake and the speed at which it is traveling. (Fig. 6)

Droppings/Scat

Snake droppings, like those of birds, usually have a cap of white calcareous material at one end. The size of the droppings corresponds to the size of the animal (and the size of the prey item digested). Snake droppings are cordlike, with constrictions and undulations.

Shed Snake Skins

Depending on the species, diet, age and climatic conditions, a snake typically sheds its skin two to three times per year. You can tell when it is ready to shed because its eyes look bluish-white and dull. Snakes may even become temporarily blind until the old skin splits at the head and they are able to crawl out. Shed skin looks like thin, clear plastic. Every detail is preserved, including the scales and eye covers. Look for shed skin under boards as well as in rock piles, stacked firewood and other places where snakes congregate.

If the shed skin is in good shape, it is possible to identify the species by counting how many rows of scales there are, checking whether the scales are keeled or smooth, looking at the anal plate is divided, and checking the skin for pattern remnants. If you find a snake skin and want to try to identify the species, consult the books and internet sites listed under "Additional Resources".

Tips for Attracting Snakes

In addition to the persecution snakes experience routinely at human hands, they have suffered greatly from our activities that alter habitat. Snakes fare poorly when we break up natural lands for urban and suburban development and isolate animals that cannot easily move across inhospitable terrain. To provide safe spaces on your property for snakes:

Rock Wall

Figure 7: Drawing Credit - Jenifer Rees

  • Protect hibernation sites and other retreat areas such as rock piles and downed woody debris.
  • Mow at a slow speed and be ready to step on the clutch or brake. Leave grass un-mowed in places that adjoin a wet area, sunny forest edge, or any other suspected snake habitat. If the grass has to be cut, survey the area and move or "herd" snakes to move to a safe location prior to mowing. Set the mower blades as high as possible, or use a weed-whacker and leave grass six inches or higher.
  • Build a fish-free pond. Many snakes feed on tadpoles, adult frogs and invertebrates found in and around ponds. Because fish compete with snakes for amphibians, making the pond fish-free will provide most snakes with the best opportunity for feeding. (See "Additional Resources" for more information about landscaping for wildlife.)
  • Build or maintain a rock wall or a rock pile with crevices for snakes to escape from severe weather and predators, to find food and to give birth (Fig. 7 ).
Snake Board

Figure 8: Drawing Credit - Jenifer Rees

A rock wall or pile of rocks provides snakes protection. (Fig. 7)

  • Create a "snake board" by laying a sheet of plywood or corrugated sheet metal on the ground in a sunny location, propping it up on three sides with three-inch rocks, lengths of plastic pipe, or similar objects (Fig. 8). In cool areas, paint the top black or cover it with dark asphalt shingles to increase the temperature below the board.

Snakes will seek out the shelter of a "snake board" in areas where a similar type of shelter is lacking. (Fig. 8)

  • Place habitat-enhancement features, such as snake boards and rock piles, away from driveways or heavily traveled roads.
  • Discourage cats from using your yard. Cats are effective hunters and can severely decrease the snake population.

In addition, you can encourage your friends and neighbors to protect snakes too, especially on property that adjoins yours. More generally, you can support public acquisition of greenbelts, remnant forests, and other wild areas in your community and join a local conservation organization, land trust or habitat enhancement project.

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Preventing Conflicts

Because of misconceptions, many people fear snakes and consequently try to eradicate them. The first thing you should do when encountering a snake, though, is to leave it alone. Next, as long as it is not inside a house or building, continue to leave it alone. The chances that you will ever see the animal again are fairly small.

If a snake gets into a building accidentally: These animals will usually attempt to escape because the "habitat" is unsuitable. They are generally small animals that will likely die from lack of food or moisture if not captured and removed.

First of all, remain calm. If you disturb it, you will force it into hiding. Then, try to remove it. Open a nearby door and use a broom to gently herd the animal out. You can also use a long pole, stick or golf club to pick a snake up and place it in a box or wastebasket to transport outdoors. If you are squeamish, use barriers such as boards or boxes to confine the snake in a room or corner, then seek a neighbor or experienced handler to capture it. If possible, slowly place an empty pail or wastebasket over a small or coiled snake until someone else arrives.

You can also hire an animal damage control agent or company to do the job. Call your regional wildlife office for a referral or look under "Animal" or "Wildlife" in your phone directory or on the Internet.

If snakes enter to find prey or shelter: Some snakes hibernate in older houses, cellars or crawl spaces with dirt floors. The presence of shed skin may indicate that a snake has taken up residence, or the snake may have used the house/cellar as temporary refugia while it shed its skin.

Snakes usually enter at ground level, so sealing all ground-level holes or cracks can prevent their access. Seal all cracks and holes in building foundations and exterior walls – including warped siding – where a small snake could enter. Use quarter-inch mesh hardware cloth, caulk, mortar or a concrete patch to make the seal.

Snakes can find easy access to garage areas through open garage doors or under poorly fitting doors. Cover door bottoms with metal flashing or a rubber gasket. Or, use tight-fitting weather-stripping along the garage and other outside doors. These modifications will also help exclude mice and other rodents, whose presence alone may attract snakes.

If snakes live around your house: In this situation, you need to modify the habitat by reducing the food supply and shelter, and encouraging natural predators. The reduction of shelter such as rock piles, woodpiles, tall grass not only limits hiding places, but also reduces the habitat used by mice and other rodents, which are a food source for snakes. (Snakes will also use holes made by mice or other rodents.) Reduce the mice and rat populations by cleaning up spilled seed under bird feeders and making other food inaccessible.

Note: Although snakes don't make up the majority of any predator's diet, hawks, owls, and a wide range of mammals eat them. As the number of snakes goes down, the number of mice, voles and other rodents may increase, resulting in a different variety of problems.

Fence

Figure 9: Drawing Credit - Jenifer Rees

To create a one-way door: Seal all the openings except the suspected main entrance. On that opening, install a one-way door made from a piece of aluminum window screen rolled into a cylinder about 10 inches long and with a slightly larger diameter than the entrance hole. Suspend the outlet end of the tube off the ground to prevent the returning snake from finding the entry. The device may be left in place for a month or longer to allow time for the snake to leave. Make any necessary repairs to the house or other structure to prevent the problem from reoccurring.

To fence out snakes: Make a fence from quarter-inch mesh galvanized hardware cloth, 30 inches high. Bury the bottom edge three to six inches in the ground, placing the support stakes inside the fence to prevent snakes from crawling up them. You can construct this fence alone or add it to the front of an existing fence. Any gate should fit tightly and be kept closed. Regularly inspect the fence to be sure that holes haven't been opened under it, and that items have not been piled against the outside. Mow grass and weeds around the fence.

A snake fence should slant outward at a 30-degree angle toward the area containing snakes. (Fig. 9)

To repel snakes: Snake repellents, such as Snake-A-Way and the stronger Doctor T's Snake Away © have produced mixed results. Snakes "smell" things via their tongues and the Jacobson's organ, which is located in the roof of the mouth. But, unlike mammals, snakes have no sense of smell associated with their breathing cycle. Unless the snake just happens to poke its tongue out at the precise moment that it is moving over the repellent, it will not notice a thing. Even if it does, the smell may not be noxious enough to drive the snake in another direction.

To trap a snake (a last resort): Make a live trap from a 24- to 36-inch section of four-inch PVC pipe. Temporarily cap one end and close off the other end with a cap that has a one-inch hole drilled through the center. Place a hand warmer and a soft cotton rag in the far end of the tube. The hand warmer will gently heat the tube and provide a lure for a cold snake. If the PVC trap feels too hot or cool, drill a few air holes in the top of the tube to ventilate. Anchor the trap to prevent it from rolling. A tracking patch (a bit of talcum powder) in front of the trap will confirm that a snake has entered. Place a piece of duct tape over the hole before moving the snake and trap outside.

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Public Health Concerns

Non-venomous snake bites are harmless. As with any injury that breaks the skin, the only concern may be for potential infection. If someone has been bitten, clean and sterilize the wound as you would any cut or abrasion. A few people may be allergic to what are usually harmless bites, such as those from a garter snake. Contact your physician if a rash or sign of infection appears.

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Legal Status

Without the proper permit, it is unlawful to import or possess any snake species that is not on the state's unrestricted wildlife list. Furthermore, the taking of snakes from the wild for export or commercial purposes is prohibited in Maine. The northern black racer (Coluber constrictor) is listed as Endangered in Maine and therefore it is unlawful to take or harass this species.

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Additional Information

Books

New England Wildlife, Habitat, Natural History, and Distribution
Written by: Richard DeGraff, and Mariko Yamasaki
University Press of New England, 2001.
(Available from: www.upne.com)

A Field Guide to Reptiles and Amphibians of Eastern North America
Written by: R. Conant and J.T. Collins
Boston: Houghton Mifflin, 1999.

Maine Amphibians and Reptiles
Written by: M.L. Hunter, A.J.K. Calhoun, and M. McCollogh (eds.)
Orono: University of Maine Press, 1999.

Snakes of the United States and Canada
Written by: C.H. Ernst and E.M. Ernst
Smithsonian Books, 2003.

Landscaping for Wildlife in the Pacific Northwest
Written by: R. Link
Seattle: University of Washington Press and the Washington Department of Fish and Wildlife, 1999.

Habitat Management Guidelines for Amphibians and Reptiles of the Northeastern United States
Written by: J.C. Mitchell, A.R. Breisch, and K.A. Buhlmann
Montgomery, Alabama: Partners in Amphibian and Reptile Conservation, Technical Publication HMG-3.

Internet Resources

Adapted from: "Living with Wildlife in the Pacific Northwest"
(see Washington Department of Fish and Wildlife)

Written by: Russell Link, Wildlife Biologist, Email Russell Link, with assistance from WDFW Biologists Rich Beausoleil and Rocky Spencer

Design and layout: Peggy Ushakoff, ITT2

Illustrations: As credited

Copyright 2005 by the Washington Department of Fish and Wildlife


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