Werler and Dixon’s Texas Snakes by Jonathan Crowe
The OHS News 87 (Dec. 2000)

Texas Snakes: Identification, Distribution and Natural History
by John E. Werler and James R. Dixon
University of Texas Press, 2000. Hardcover, xv + 437 pp. + plates.
ISBN 0-292-79130-5

Work began on this book twenty years ago, the authors inform us in the preface. Even taking into account the fact that for most of that period, the authors had other responsibilities and could not have worked full-time on this project, that seems an awfully long time to spend on a single work. Looking at the book, though, it is easy to see why. It has all the usual sections you would expect from such a guide: a general introduction, an identification key, a note on venom, an extensive bibliography and, of course, species and subspecies accounts. But those accounts have a level of detail and thoroughness that are unmatched by any other guide, including Tennant’s Field Guide to Texas Snakes, and each gives an in-depth survey of the scientific knowledge of the snake in question. With so much attention paid to each of Texas’s 109 species and subspecies, no wonder it took so long.

The range maps, which astonishingly were not generated by computer, are extraordinarily detailed and precise. Instead of just a shaded area covering a snake’s general range, dots show precisely where specimens of a given snake were found, and the maps are large enough and detailed enough to show rivers and county boundaries. In southwest Texas, interestingly, the dots are frequently densely packed along lines — presumably the highways along which the specimens were collected! One point of confusion is that the shaded areas around the dots indicate the subspecies, while the dots themselves indicate the species. Thus, for example, the dots on the maps for the Speckled Kingsnake (Lampropeltis getula holbrooki) and the Desert Kingsnake (L. g. splendida) are identical, except that the shading for each indicates which dots belong to which subspecies. A related wrinkle is that, unlike the Gulf field guides, zones of integradation are not shown: a locality belongs to one subspecies or the other, with no room for ambiguity.

Then there are the illustrations — 208 colour photographs, most of which are large and many of which are breathtaking, and dozens of line illustrations. No skimping here.

Taxonomy is always a sure point of contention. Nitpickers will certainly find enough reason to complain, since this book does not always follow the standard common and scientific names established by Collins. The authors do not necessarily follow the logic that allopatric populations are distinct species, and make calls on a case by case basis. Whatever they’re called, the snakes remain the snakes, and it should make no difference to the usefulness of this book.

Texas Snakes is the best guide to North American snakes that I have yet seen, and though its sheer bulk makes it of limited use as a field guide, it is strongly recommended for anyone with an interest in the snakes in question.

Note: This article has not been updated since its first publication. As a result, some of the facts referred to in the text may now be out of date.