I recently had a debate with some colleagues over the representation of some snakes as venomous. Someone had asked why certain venomous snakes, like the Eastern Hognose Snake (Heterodon platyrhinos) were never labeled as venomous on posters and other informational materials from the state game agency. Actually, she asked whether they were really venomous because they were never represented as such, and if so, why were they not represented that way. Well, a heated debate ensued about accurately representing these animals vs. "fudging" the facts so as not to give the snakes a bum rap. I was on the side of fudging. My point was that the label was only a part of the whole message, and that how the labels were displayed and in what context came together to convey information. A poster with the image and name of a snake with a bold red label that reads "VENOMOUS", is not just saying that the snake is venomous, it is also saying that the snake is dangerous. Other people opined that the posters should be accurate and that the reader/viewer of the media should be trusted to know the facts. I think both arguments have merit, but I still insist that the entirety of the representation should be considered and that representing a snake that is harmless with a bold label is a misrepresentation and I believe that the state wildlife agencies also see it that way, which is why harmless, yet venomous, snakes are often not identified on those kinds of media.

That all being said, it is important to note that there are, in fact, many harmless yet venomous snakes. To be considered venomous, the snake must possess the apparatus of a venomous snake. This apparatus consists of a special gland that produces a toxic substance and enlarged teeth for delivering that substance. Typically identified venomous snakes usually belong to one of two families of snakes, the elapids or the viperids.

Elapids are represented in the U.S. Coastal Plains by the Eastern Coral Snake (Micrurus fulvius fulvius) and are possessed of relatively short fangs that are fixed on the front of the maxilla. Viperids in the U.S. Coastal Plains (and, in fact, the entire new world) are all members of one sub-family, the crotalines or pit-vipers, and have relatively long fangs on the maxillae; so long, in fact, that they fold against the roof of the mouth. Both viperids and elapids have venom glands that are situated to the anterior of each eye and have fangs that are hollow so as to act like a hypodermic needle. Also, all members of each of these families are venomous and many are dangerously so.

There is another group of snakes that has venomous members. That family is called colubridae, but not all of its members are venomous. In fact, most are not venomous and its members include the rat snakes and king snakes. Most of the venomous colubrids have rear fangs: enlarged teeth in the back of the mouth instead of the front. Instead of being hollow, these teeth are usually, though not always, grooved and instead of a full venom gland, they have a reduced, simpler organ called a Duvernoy's gland. The Duvernoy's gland still produces toxin, but it is not as advanced as a venom gland. Although rear-fanged snakes in other parts of the world can be deadly to humans, none in the U.S. are considered dangerous. In fact, most of these snakes are less dangerous than many non-venomous snakes. That is because the venom apparatus is there only to subdue the snakes prey (usually frogs, toad and lizards). A quick survey of these snakes will reveal animals that are often slight of build and not endowed with great physical strength. The prey for these snakes can be stronger than they are and could injure the snake while struggling to escape. Most of these snakes seldom, if ever, bite humans, even when first grabbed and handled and the venom is so weak that there is no meaningful effect on people.

The point that should be noted here, is that the fact that some colubrids in the U.S. are venomous is really a point of scientific detail and is only of interest to people who study them. To the layman, the most important thing to note is whether or not the snake in question is dangerous. All of the viperids and elapids in the U.S. should be considered dangerous. NONE of the colubrids(both venomous and non-venomous), should be considered dangerous. Creators of informational media regarding snakes should carefully consider how they word things in this regard and should use the phrase "Dangerous" or "Dangerously Venomous" instead of simply "Venomous". It should also be mentioned here that there are no "POISONOUS" snakes; you can eat any of them :-).