There's been some discussion here recently regarding whether E. obsoleta, and in particular the Texas Rat Snake (E. o. Lindheimeri) has an undeserved reputation for being overly aggressive relative to other Elaphe species/subspecies. From my experience in this neck of the woods (central OK), where intergrades of both subspecies are relatively common, I can see easily how differing conclusions could be drawn on this subject. Because, after many years of herping and the resulting experience in sensing the overall disposition of many different snake species, I can honestly say that I have never come across another species in which general level of aggressiveness varies so much from one specimen to another! (I'm basing this on WCs.)
I have encountered some that were very docile from the start, some that began with an attitude but tamed down after a time, and yet others that were downright nasty and had no intention of ever changing. Most vibrate their tails when first encountered, but some don't. Some hiss loudly, but most do not. They nearly all do the musk thing, tho.
The differences in disposition seem to have no bearing on size, age, coloration, or any other characteristic. And in this region of intergrades, there is considerable variation in strength of pattern among individuals. Some become dark as juveniles, but I've also seen adults that were patterned strongly enough that they might be full Texas Rats. But virtually all specimens around here, including 5-6 foot adults, have quite a bit of brown/yellow/red/white speckling and some level of dorsal blotching on the scales (not just the skin between). So I personally think there may be no such thing as a pure Black Rat or a pure Texas Rat in this area. (A purist's nightmare, and perhaps fodder for another thread!)
I think we all know that individual serpents each have their own individual "personalities," but also that nearly all species have general behavioral characteristics that tend to surface in nearly all specimens of their particular species. I just think it's interesting that Elaphe obsoleta (obsoleta, lindheimeri, or interegrades thereof) seem to be among the most variable around when it comes to expected disposition.
Cheers, Michaelb
