Reptiles
Milk Snake
Lampropeltis triangulum · also called milk snake, milksnake
The milk snake is a harmless barn-dweller wearing a warning it never earned. Its red, black, and yellow bands are a close copy of the venomous coral snake’s, good enough to make predators — and people — keep their distance. Its name comes from a myth about snakes milking cows.
Overview
The milk snake has one of the widest ranges of any New World snake, from southeastern Canada to Ecuador and Venezuela, across forest, grassland, farmland, and desert. It is a kingsnake — a constrictor — and eats rodents, lizards, birds, eggs, and other snakes, including venomous ones, to whose venom it is largely resistant. It is secretive, mostly active at night and dusk, and much more common than it is seen.
Borrowed protection
Southern banded milk snakes closely resemble the venomous eastern coral snake. Predators that have learned to avoid coral snakes also avoid the harmless mimic — Batesian mimicry. In the US, the tell is band order: coral snakes have red touching yellow; milk snakes have red touching black (“red touch yellow, kill a fellow”). The rule fails in Latin America, where the patterns overlap, so an unidentified banded snake is best left alone.
The milk myth
Milk snakes turn up in barns and dairies, and farmers once believed they suckled milk from cows. They were really hunting the mice the grain attracted — a snake cannot suckle at all.
Status
The milk snake is Least Concern and common, though many are needlessly killed by people who mistake the mimic for the real thing.
Milk Snake: common questions
Are milk snakes venomous or dangerous?
No. Milk snakes are completely non-venomous and harmless to people. They are a type of kingsnake, and they kill prey by constriction — seizing it in the jaws and quickly throwing coils around it to stop its circulation. A cornered milk snake may hiss, vibrate its tail against dead leaves to imitate a rattlesnake, and deliver a quick nip, but the bite is trivial, causing at most a few pinprick scratches. Their resemblance to venomous coral snakes leads to many being killed by frightened people, which is unfortunate because milk snakes are valuable controllers of rodents and, being partly snake-eaters themselves, will even hunt young venomous snakes.
How do you tell a milk snake from a coral snake?
In the United States, the reliable difference is the order of the coloured rings. On a venomous coral snake the red and yellow bands touch each other; on a milk snake the red bands are bordered by black. This is the origin of sayings like "red touch yellow, kill a fellow; red touch black, friend of Jack." A coral snake also has a blunt black snout, while a milk snake's snout is lighter, and coral snakes have thin bands that fully circle the body. Important caveats — these rules only work for the US species, they do not apply to the many coral and milk snakes of Mexico, Central, and South America where the patterns overlap, and rhymes are easy to misremember — so the safest rule anywhere is simply not to handle a red-black-yellow banded snake you cannot positively identify.
Why is it called a milk snake?
The name preserves an old and completely false piece of farm folklore. Milk snakes are frequently found in and around barns, dairies, and outbuildings, and people once believed the snakes went there at night to drink milk directly from the udders of cows, sometimes blaming them when a cow's yield dropped. In reality snakes have no ability to suckle — their teeth would injure the cow and their throats cannot manage that kind of feeding — and they are attracted to barns because barns are full of mice and rats. The snake was doing the farmer a favour, not stealing from him.
Is the milk snake a good pet?
Yes, milk snakes and other kingsnakes are among the most commonly kept pet snakes and are generally recommended for beginners. They are hardy, stay a manageable size in most of the popular subspecies, feed readily on appropriately sized rodents, and become tolerant of handling. The main husbandry notes specific to them are that they are strong escape artists and need a very secure lid, and that they are cannibalistic snake-eaters in the wild, so they must always be housed alone. Captive-bred milk snakes are widely available in a range of natural and selectively bred colour forms.