Head to head
Eastern Coral Snake vs Milk Snake
The coral snake and the milk snake are a textbook case of mimicry. The coral snake has a potent neurotoxic venom; the milk snake is a completely harmless constrictor. Both are ringed in red, black, and yellow or white, and the milk snake's resemblance to the coral snake is thought to give it some protection from predators that have learned to avoid the deadly pattern.
| Eastern Coral Snake | Milk Snake | |
|---|---|---|
| Family | Elapid, a cobra relative | Colubrid, in the kingsnake group |
| Venom | Potent neurotoxin; bites are serious | None; kills prey by constriction |
| Band order (US) | Red bands touch yellow bands | Red bands touch black bands |
| Head | Black snout; blunt head, not wider than the neck | Often a pale V or blotch; head slightly distinct |
| Size | About 60–90 cm, slender | About 50–130 cm depending on subspecies |
| Behaviour | Secretive, mostly underground; reluctant to bite | Secretive, nocturnal, harmless; may musk or buzz its tail |
| Diet | Other snakes and lizards | Rodents, birds, eggs, lizards, other snakes |
| Bite | Small fangs, must chew; envenomation uncommon but dangerous | A harmless nip at most |
Coral Snake vs Milk Snake: common questions
How do you tell a coral snake from a milk snake?
In the United States, look at which colours touch. A coral snake has red bands bordered by yellow, so red and yellow rings sit next to each other. A milk snake or scarlet kingsnake has red bands bordered by black. The rhyme "red touches yellow, kills a fellow" captures this. A coral snake also has a solid black snout, while a milk snake usually has some pale marking on the head.
Does the "red and yellow" rhyme always work?
No. It is reliable only for the coral snakes and their mimics in the United States. The dozens of coral snake species in Mexico, Central America, and South America have all sorts of band arrangements, including some where red touches black, so the rhyme would tell you a venomous snake is safe. Outside the US, colour order is not a safe guide, and any brightly ringed snake should be left alone.
Why does the milk snake look like a coral snake?
It is thought to be Batesian mimicry, in which a harmless species copies the warning signals of a dangerous one. Predators such as birds of prey that have learned, sometimes fatally, to avoid the coral snake's red, black, and yellow rings will also tend to avoid a milk snake wearing a similar pattern, even though the milk snake could not hurt them. The resemblance does not have to be perfect to work.