That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information

The black ratsnake, Elaphe alleganiensis, found throughout much of the eastern half of North America (even in NYC, on occasion, and its suburbs), is a pet trade staple. Hobbyists have developed a number of unique color morphs, including albino individuals, and frequently hybridize this snake with related species. Since so much is known of its natural history and captive care, I thought I would note here some recent changes regarding its relationships to similar snakes.

The taxonomy of the genus Elaphe is confusing due to a wide variation in the appearance of individuals of the same species, and to the fact that the various species and subspecies inter-breed where their ranges overlap (one reason for the ease in creating different color phases in captivity). Most snake enthusiasts grew up knowing the black ratsnake as Elaphe obsoleta, but that name is a now assigned to the Western ratsnake, with the black ratsnake being re-named as E. alleganiensis. At least 11 species of snake of the genus Elaphe are found throughout North America.

To add to the confusion, black ratsnakes living from North Carolina through the Florida Keys vary greatly in appearance from northern populations, being various shades of yellow and orange in color instead of black. Formerly classified as distinct subspecies, known as Everglades ratsnakes and yellow ratsnakes – both also quite popular in the pet trade – they are now considered to be merely local color variations of the black ratsnake.

The black ratsnake frequently shares hibernation dens with rattlesnakes and copperheads. In some parts of the country it is known as the “pilot blacksnake” or “rattlesnake pilot”, in the mistaken belief that it guides rattlesnakes to their winter retreats. The largest individual on record measured 8 ½ feet long.

The latest information concerning changes in reptile classification and taxonomy is available at the website of the American Museum of Natural History’s herpetology department:
http://www.reptile-database.org/

A general principle of reptile-keeping holds that “several small meals are better than one”, but there is no denying the fascination aroused by the swallowing abilities of the giant constricting snakes. I myself, even after decades of working with large snakes in zoos, was stunned when a 17 foot long anaconda I helped to capture in Venezuela disgorged a deer weighing 60 pounds (this at 3AM, below the hammock upon which I was trying to sleep)! I also observed anacondas swallowing a large side-necked turtle, Podocnemis unifilis, a 5 foot long spectacled caiman, Caiman crocodilus and a 10 pound red-footed tortoise, Geochelone carbonaria. Keepers at the Singapore Zoo informed me that a free-ranging reticulated python consumed a 40 pound cape hunting dog exhibited there.

Perhaps the most startling account is given by the Carl Hagenbeck of the Hamburg Zoo – a 25 foot long reticulated python in his collection consumed a 71 pound ibex (wild goat) several days after eating two goats of 28 and 39 pounds, for a total of 138 pounds of food within a few days! The largest meal reliably documented to have been taken by any snake seems to be the 130 pound impala eaten by an African rock python, P. sebae in South Africa(recorded by W. Rose, 1955). The group’s most “elegant” meal must surely be a Siamese cat (including bells and collar) that was taken by a reticulated python that wandered into the palace of a former king of Thailand!

Reticulated pythons are, along with anacondas, Burmese pythons, P. molurus, and African rock pythons, the only snakes known to have consumed people. I have had, unfortunately, first-hand experience with a feeding-accident fatality in NYC. Obviously, giant snake ownership is not to be undertaken lightly.

I would be very happy to learn of your own observations of snakes large and small, and to entertain your questions. Thanks.

An engrossing overview of giant snake behavior is given by famous herpetologist Clifford Pope in The Giant Snakes, 1961, A. Knopf, NY. You can also find further information at:
http://www.reptileknowledge.com/