Eastern Hog-Nosed Snake Heterodon platirhinos

Adult from Jefferson County

Identification

Eastern Hog-Nosed Snakes are some of the most unique snakes in Indiana, largely by virtue of their peculiar defensive behaviors. Though quite variable in color and pattern, no other snake exhibits such dramatic behavior when threatened. When encountered, a hog-nosed snake may hiss loudly and flatten its neck and head in an almost cobra-like fashion. If this fails to scare away a would-be attacker, they may strike open-mouthed at the perceived threat. If all else fails, Eastern Hog-Nosed Snakes sometimes put on an exaggerated death-feigning display in which they flail around on their back, mouth agape, and ultimately come to rest, after numerous convulsions, upside down, tongue lolling out. Aside from this behavior, Eastern Hog-Nosed Snakes also have a uniquely upturned snout for burrowing. They are otherwise robust snakes that may be gray-brown to orange-yellow with irregular black blotches. Melanism is common among Eastern Hog-Nosed Snakes and many individuals are entirely black or slate-gray. Most adult Eastern Hog-Nosed Snakes are two to three feet (60 - 90 cm) long, but some may approach four feet (1.2 m) in length.

Adults from Brown County
Death-feigning Behavior

Although Eastern Hog-Nosed Snakes have unmistakable defensive behaviors, the wide range of color variants they sport can make identifying an unprovoked snake difficult. In particular, Northern Watersnakes, Eastern Milksnakes, and Copperheads are superficially similar due to their banded pattern. However, all other species lack the distinct upturned snout for which Eastern Hog-Nosed Snakes were named.

Ecology and Conservation

When threatened, the Eastern Hog-Nosed Snakes exhibits perhaps the most unusual bluffing behavior of all the species of Indiana’s snakes. This behavior begins with the snake inflating its head and coiling. It will hiss loudly and strike (with its mouth closed). If this display fails to scare a potential predator away, the Eastern Hog-Nosed Snake plays dead by rolling over on its back with its mouth open and tongue hanging out. It may also release a foul smell. Curiously, if the “dead” snake is placed back on its belly, it quickly dies again, rolling upside-down yet another time. The snake remains in this position until it feels safe, then has a look around and moves away. The Eastern Hog-Nosed Snake is found in dry habitats such as fields and forest edges. It preys primarily on toads and salamanders.

Although it may be locally abundant, it is not a common snake and has disappeared from many areas.

Trashy field in northern Illinois

Distribution

Eastern Hog-Nosed Snakes occur throughout Indiana, but are most prevalent in regions with sandy soil and abundant toads, their primary prey. They are also common in the unglaciated hills of southern Indiana. They are good burrowers that spend some time underground, but are often seen crossing roads during the spring and summer.

The distribution of the Eastern Hog-Nosed Snake extends from Massachusetts to Minnesota and south from Florida to Texas. It is found in every state in the Midwest.

Taxonomy

No subspecies of the Eastern Hog-Nosed Snake (Heterodon platirhinos) are currently recognized. These snakes are members of the family Colubridae, which is represented by a total of 28 species in Indiana.

Literature Cited

Conant, R. and J. T . Collins. 1998. Reptiles and Amphibians of Eastern and Central North America. Third Edition, Expanded. Houghton Mifflin, New York, NY.

Minton, S. A. Jr. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Indianapolis, IN.

Distribution Map
Distribution map of Eastern Hog-Nosed Snake (Heterodon platirhinos)
Photographs