The rhyme to differentiate coral snakes from king snakes could get you killed

Growing up in Louisiana, I always heard this rhyme that was supposed to help me differentiate between dangerous (coral) snakes and harmless (king) snakes. There were a couple of problems, though, with using the rhyme in practice. First, I never wanted to get close enough to a snake to look at its color patterns. Second, I literally could never remember the rhyme. Red and yellow, kill a fellow, red and black, all fine, Jack? Red or yellow, kill a fellow, Red or black, all fine, Jack? I'm bad with remembering cliches and rhymes, always have been. 

Recently in a group, I belong to on Facebook, Derpetology, a member made a post saying that we should abandon this rhyme because it's confusing and sometimes inaccurate. So I decided to go find out what the story was. According to the website Wild Snakes Education and Discussion, there are four main controversies regarding the rhyme:

The first controversy is that sometimes (rarely) a snake will be found that does not look like the field guide photo. These snakes are called "aberrant" and they often have markings and colors that are different – sometimes extremely different – from the "normal" version of the species.

The second controversy is the existence of a snake native to the southwestern U.S., the Shovel-nosed Snakes (Chionactis sp.) These small, harmless snakes do have red and yellow bands touching, which may cause confusion and could result in these snakes being killed.

The third controversy is that the rhyme is often misquoted and mixed up which could cause someone to mistake a coral snake for a non-venomous species.

The fourth, most dangerous, and 100% accurate argument is that the rhyme is only reliable when in reference to coral snakes native to the United States. Once we enter Mexico and down through South America, we encounter dozens of coral snake species which do not follow any rules or rhymes. To add to the confusion there are also dozens of coral snake "mimics" in Central and South America and Mexico. These range from non-venomous species to rear-fanged and venomous species.

The Venom Interviews website also is very clear that when it comes to identifying coral snakes, "You can't always trust the 'red-on-yellow' rhyme." And Reptiles Magazine agrees that, "Red Touch Yellow, Kill A Fellow Doesn't Always Work." So what are we supposed to do? Wild Snakes Education and Discussion explains that it takes a lot of patience and education to learn how to identify snakes, and caution that we should never simply rely on one source of information like a rhyme. They offer these guidelines

  • The rhyme can be used only in conjunction with other features to identify snakes.
  • The rhyme is only to be used in reference to coral snakes native to the United States.
  • When in doubt do not touch or handle a snake you cannot reliably identify!

Sounds like a great plan. My other go-to when I encounter a snake is to just back away slowly and then run the other way, but that's just me!