Milk snakes can be from 35 to 175 cm long, with the longest snakes being found in Mexico and Central America. In the United States lengths are usually 60 to 130 cm. They are very colorful snakes and their colors vary throughout their range. All milk snakes have a blotchy or striped appearance, with darker blotches separated by lighter stripes. The color of those darker blotches can be very light to very dark, from tan to rust colored to dark brown. The ligher areas can be orange, yellow, or white. The darker areas are always outlined in black. Milk snakes have 19 to 23 rows of smooth scales and a single anal plate.
Milk snakes are found throughout the eastern United States, into southern Canada, and south into Mexico and Central America. They have a Nearctic distribution.
Milk snakes can thrive in a variety of habitats. They are usually found near forest edges, but can also be found in open woodlands, prairies and grasslands, near streams and rivers, on rocky hillsides, and in suburban areas and farmlands. Milk snakes are not rare but are secretive, so are rarely seen.
Milk snakes mate while in their hibernation spots before they emerge in the spring.
Milk snakes lay from 2 to 17 (usually about 10) elliptical eggs in rotting logs or moist, warm leaf litter. They hatch after 28 to 39 days and emerge as young milk snakes that are 14 to 28 cm long. Upon hatching they are brightly colored, with oranges, reds, purples, and yellows. Their colors become more dull as they age. Young milk snakes become fully grown in 3 to 4 years.
Milk snake females choose nest sites that are warm and humid. Once the eggs are laid there is no further parental care.
Lifespans of milk snakes aren't well known. However, on individual lived in captivity to be more than 21 years old. Most milk snakes probably die in their first year of life.
Milk snakes are solitary species, they are only found with other milk snakes during their winter hibernation, when they travel to hibernation sites that will protect them during the winter from extreme weather. Milk snakes are most active during the day but are rarely seen then, because they are secretive. They can sometimes be seen basking on rocks and roadways during cool weather and at night. Milk snakes can stay active even when the weather is very hot, when other snakes usually try to take refuge from the heat.
Not much is known about milk snake communication. They use sight, hearing, touch, and smell to perceive their environment.
Milk snakes are carnivorous. Adults feed mainly on rodents such as voles, white-footed mice, and house mice , but will also eat birds, bird eggs, lizards, snake eggs, or other snakes, including venomous species like coral snakes and rattlesnakes. Young milk snakes seem to feed mainly on other young snakes. When prey is captured, it is constricted (squeezed) until it suffocates. It is then swallowed whole.
Milk snakes are prey for animals such as raccoons, foxes, skunks, and coyotes. When they feel threatened, milk snakes will vibrate their tails, trying to look like a venomous rattlesnake. Their color pattern of alternating black, white, and reddish stripes also makes them look like another venomous snake, coral snakes. In some areas their color patterns mimic copperhead snakes, which are also venomous. By looking like dangerous snakes they avoid being preyed on by many animals, but this often backfires when humans mistake them for the dangerous snake and kill these otherwise harmless and helpful snakes.
Milk snakes are important predators of small mammals, birds, and other snakes.
There are no negative affects of milk snakes on humans.
Milk snakes have a close relationship with humans, as they are commonly found in farmland or urban areas. These snakes are beneficial to humans as they feed on rodents that concentrate around barns or trash (Vogt 1981).
Though milk snakes are often killed by humans who mistake them for venomous snakes, they are widespread and still considered abundant throughout most of their range. (Canadian Amphibian & Reptile Conservation Network, March 1999)
The milk snake got its name from an Old World folk tale. The tale tells that the snake sucks the milk of nursing mothers and cows until they are dry. Of course we know this to be impossible because the snake is harmless and a human mother or a cow would certainly not allow it. Also, the snake's belly could only hold a few tablespoons of milk (Vogt 1981).
Canadian Amphibian & Reptile Conservation Network, ,. March 1999. "Lampropeltis triangulum Milk Snake" (On-line). Accessed November 7, 1999 at http://cs715.cciw.ca/ecowatch/dapcan/reptiles/tour/glossary/milksnk2.htm.
National Audubon Society Inc, ,. 1979. National Audubon Society's Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knopf, Inc..
Roth, J., H. Smith. 1990. The milksnake, Lampropeltis triangulum, in northwest Colorado. Bulletin of the Chicago Herpetological Society: 6-7.
Vogt, R. 1981. Natural History of Amphibians and Reptiles of Wisconsin. Milwaukee, Wisconsin: Milwaukee Public Museum.
Williams, K. 1994. Reptilia:Squamata:Serpentes:Colubridae:Lampropeltis triangulum. Catalogue of American Amphibians and Reptiles: 594.