SNAKES ON A BRAIN: THE EASTERN HOG-NOSED SNAKE

By Romey Swanson of Plateau Land & Wildlife Management

Snakes.

Just the word can elicit a visceral and polar reaction. You are either in the category of people whose skin crawls as visions of tangles of cottonmouths (a myth) and 10 foot long rattlesnakes (another myth, although 6 footers in South Texas were once common) are evoked. Or you are in the minority of those who respect from a distance or even, dare I say, actually enjoy these critters. No matter what your response, it is essential to understand that these animals belong to a healthy ecosystem and are necessary components of a complex and elaborate set of relationships weaved together to create the environment in which we live. For those who read that previous sentence and thought something along the lines of "I don't think so, pal", I would like to challenge you to familiarize yourself with just a few of the more common snake species around, their natural history, what they do, where they live, and their relationships.

One snake that has an especially interesting natural history is the Eastern Hog-nosed Snake ("the hognose"). This large bodied serpent reaches lengths of 24-36 inches and can commonly be found in the sandy soils of open canopy woodlands of the eastern half of Texas. Within the Edwards Plateau, the hognose is considered less common but can be found along rivers, streams, and larger bodies of water where appropriate habitat is available. It prefers this habitat primarily because the hognose likes to bury in the loose sandy substrate and leaf litter during the heat of the day, and this habitat is where the hognose can find its favorite meal, toads. Not many animals will attempt to consume a toad whole. Just think back to the last time the family dog came back foaming at the mouth and slobbering everywhere! The hognose combats the poisonous quality of a toad's bufotoxin (a chemical depressant in the common toads of our area) by way of enlarged adrenal glands, which translates to increased adrenaline production. Ultimately, this allows the snake to consume a locally abundant food source and assist in keeping toad populations in check. The hognose even does well living in the midst of man where it commonly shows up in the well watered and loose soils of family gardens, where it feasts on the abundant Coastal Plains Toad (think "driveway" toad).

Perhaps even more interesting than its taste for toads, is the hognose defense mechanism which can be broken down in three phases. In phase one, the snake puffs up and hisses while holding its mouth agape, a common behavior among several species of snake. If pressed further, however, the snake will enter into phase two of the defense mechanism when it curls its tail while flaring the nape of its neck. The hognose shares this behavior with a much more famous group of snakes, the cobras. In this phase, the hognose may go as far as to strike. Although harmless and not known to be aggressive, I have experienced a "bite" from this snake and would describe it as more of a closed mouth punch that surprises more than hurts or harms -- and this only occurring after persistent molestation. Lastly, if this snake is pushed further, it will feign death, quickly contorting and wiggling as if in the final throes. All this while voiding its bowls, possibly regurgitating its last meal, and secreting foul green goo from its musk glands. Finally, the snake flips over onto its back while holding its mouth agape with the tongue hanging completely out. If you were to pick the snake up and correct its posture while in this phase, it will again roll over to its back all while showing no other signs of life. In short, if there were an Academy Award for best performance by a snake, the Oscar would go to the hognose.

Along with being a vital piece of a complex environmental puzzle, the hognose provides an interesting study on the complexities of animal behavior. It is also a prime example of a species that can co-exist in the presence of man and poses virtually no threat of harm, despite a menacing appearance. While few people will convert from fearing snakes to adoring them, it is fair to say that snakes are, indeed, "biblical" and not going anywhere anytime soon. Learning to understand, tolerate, and even appreciate their environmental purpose -- even if we don't want to be anywhere in the vicinity -- is all part of our collective conservation and preservation community.

For more information on the snakes of Texas, check out, Texas Snakes: A Field Guide by James R. Dixon.

Romey Swanson is a Plateau Products and Services Field Biologist. He received his M.S. in Wildlife Ecology in December 2009 from Texas State University. He is particularly interested in the natural history of Texas flora and fauna with a focus on mammals, reptiles, amphibians and birds. Romey is an active member of the Texas Chapter of The Wildlife Society and is currently pending certification as an Associate Wildlife Biologist from The Wildlife Society Certification Board.