Texas Rat Snake (04 May 2007)

SW Austin, Texas

(Elaphe obsoleta lindheimeri) Extremely Beneficial as a predator of mice and rats, not so beneficial for its predation on birds, but the former occupies most of its time and the latter is a minor distraction in the over-all scheme of things. This snake is a truly non-venomous colubrid, but tends to be very pugnacious and can inflict a fierce bite if cornered and not allowed to escape, or if it is handled. The productive bite of a mature adult specimen can produce a painful wound that bleeds freely from numerous puncture marks made by small, sharp teeth; otherwise the bite is generally of no medical consequence.

ROBYN WROTE: Hi, Jerry-- We saw this surprisingly large (maybe 3 to 4 feet long) snake in a red oak tree this evening. Our house backs up to a greenbelt and a flood retention pond in Southwest Austin. We often see smaller snakes in our yard throughout the spring, but we've never encountered one quite this large. The flood retention pond has been full for a couple of days. I don't know if that has anything to do with our visitor. I wish I could have gotten a better photo, but it was pretty high up and I was terrified of it. Unfortunately, I didn't see where it went, although one of my daughters thinks she saw it snap at a small bird. Can you make an id with the attached photo? If you zoom in, you can see its head pretty clearly.  Robyn C.

MY REPLY: Robyn, your snake (a beautiful specimen, I might add) is a Texas rat snake (Elaphe obsoleta lindheimeri), and is very beneficial and non-venomous.  You have nothing to fear from this fellow, unless you try to pick it up.  It is a pugnacious snake and will bite, producing--in as large a specimen as this--bloody and painful bites.  The bite is otherwise of no consequence. It preys mostly on rats and mice, and is good to have around for that reason.  Unfortunately, it will also eat birds and their eggs if given a chance.  However, its favorite food is in the form of a rodent---Jerry

ROBYN: Wow! That was a quick (and comforting) answer. It also explains why the mama owl that lives in my backyard is so restless today. She's been all over the yard today, never taking an eye off her nest box. The many other birds that hang out in my yard were pretty agitated this afternoon, too. I wonder if Mr(s) snake was after a nest in that tree. Should we assume that this snake lives in our yard or is it possible (s)he was just visiting? Also, is it safe to assume it's not going to bother us if we leave it alone? My 7-year-old daughter is convinced it was a python or a boa constrictor and she's sworn she's never going in the backyard again. . . Thanks again for your quick help. We sure have some great nature resources here in Austin! Robyn.

MY REPLY: You are probably right about the reasons behind the owl's nervousness.  By the way, owls prey on rodents and small birds, too, so it and the snake are both about equally beneficial--and culpable--in those two venues. Snakes don't travel far from good sources of prey, so this serpent will likely stay around as long as hunting is good.  Fortunately it is harmless to you, your children, and your pets (not including pet mice, hamsters, and the like, of course).  Expect to see it again. Ask your daughter to check out the photos and information on http://en.wikipedia.org/wiki/Python and http://wonderclub.com/Wildlife/reptiles/BoaConstrictor.html It will be immediately obvious to her that the snake in your red oak is neither species, though they--as a general rule that pertains to snakes no larger than six feet in length (they get much larger than that and large specimens can be quite dangerous if mishandled)--are as harmless to humans as our native rat snakes.  The Texas rat snake, however, won't hurt her unless she tries to handle it and then it may produce a painful and bloody bite that, if one needs consolation, heals rather quickly---Jerry

Its muscular body, and "D" shaped cross-section, allows the Texas rat snake climb trees with ease.  The upper body is held up by the lower body muscles as it climbs.  Note that the head is rounded, from side to side, with large eyes that have obviously round pupils (as contrasted with the cat's eye pupils of the pit vipers), and a uniformly dark gray nose and lateral face; the dorsal head is also uniformly gray as well, though it cannot be seen well in this photo. Note the pale coloration of the upper lips, which are unmarked.  The juvenile Texas rat snake has markings on the dorsal head, but mature specimens, like this one, are unmarked there except for the dark gray coloration and this feature, which is unique among our native rat snakes, assists in identifying a Texas rat snake in the field.

The mid body markings consist of saddles over the spine, separated by lighter spaces with an orange, yellow, or yellowish brown tint, and often, though not in this specimen, with conspicuous but small white markings between some of the scales.  On the sides, alternating between the upper saddles, are dark blotches ringed in the lighter coloration, usually tinged in orange, yellow, or yellowish brown; if you squint your eyes while viewing this photograph you will see what appears to be a series of lateral blotches running the length of the snake's sides. In juvenile and middle-aged specimens, these blotches look like a chain-link fence, but as these snakes age their markings darken and the effect eventually becomes difficult or impossible to see. In such cases, look carefully at the head for the uniformly dark dorsum, large round eyes with large round pupils, a rounded head (contrasted with the angular heads of many pit vipers) with large. unmarked, pale lip scales. If all these features are observed, relax, as it is likely a Texas rat snake.

SNAKE ENCOUNTERS * SNAKE BITE FIRST AID * SNAKE EXCLUSION * SPIDER ENCOUNTERS * SPIDER BITE FIRST AID * SPIDER EXTERMINATION * PUSS CATERPILLAR ENCOUNTERS * PUSS CATERPILLAR FIRST AID * PUSS CATERPILLAR EXTERMINATION * Assembled & Edited by Jerry Cates. Questions? Corrections? Comments? BUG ME RIGHT NOW! ---- Ph: 512-331-1111 ---- E-Mail ---- Privacy ---- BugsInTheNews