Other common names
Southern Hognose Snake, Puff Adder, Hissing Adder, Spreading Adder, Blow Viper, Hissing Sand Snake
Most adult southern hog-nosed snakes are about 18-22 inches (45-55 cm) in total length. These are small, stout-bodied snakes with sharply upturned snouts. Adults can be light gray, tan, yellowish brown, or orangish-red, with large dark blotches down the middle of the back that alternate with smaller dark blotches on the sides. There is often reddish-orange coloration between the large blotches on the back. There is a dark line extending from the upper jaw through the eye. Juvenile coloration is similar to that described for adults but more vivid.
Southern Hog-nosed Snakes are found throughout the Panhandle and in parts of the northern and central peninsula west of the St. Johns River. They are absent from the Florida Keys.
Assessment of risk to people and pets
Non-venomous. Southern Hog-nosed Snakes are not dangerous to people or pets. They do, however, produce a mild venom that is used for subduing prey. This mild venom is delivered by two enlarged teeth at the back of the upper jaw. However, bites from Southern Hog-nosed Snakes are extremely rare. These snakes are not aggressive and are not known to bite even in self defense. People who have been bitten were usually handling the snake after handling frogs or toads (two of these snakes’ favorite foods), and the bites were from snakes that were confused and hungry. Humans that are allergic to the small amount of venom produced have experienced local swelling and irritation, but no human death from this species has ever occurred. Virtually all bites have occurred when the snakes were intentionally handled.
Comparison with other species
Eastern Hog-nosed Snake (Heterodon platirhinos) Non-venomous typically has a darker belly than the underside of the tail, and a less upturned snout.
Dusky Pygmy Rattlesnake (Sistrurus miliarius) Venomous has a blunt nose and a small rattle on the tip of the tail.
Most adult Southern Hog-nosed Snakes are about 18-22 inches (45-55 cm) in total length, with a record length of 24 inches (61 cm). These are small, stout-bodied snakes with sharply upturned snouts. Adults can be light gray, tan, yellowish brown, or orangish-red, with large dark blotches down the middle of the back that alternate with smaller dark blotches on the sides. There is often reddish-orange coloration between the large blotches on the back. The underside of the tail and the belly are the same light color of sandy gray. There is a dark line extending from the upper jaw through the eye. The scales are keeled (each scale has a prominent raised ridge), and there are typically about 25 dorsal scale rows at midbody. The pupil is round. Juvenile coloration is similar to that described for adults but more vivid.
Southern Hog-nosed Snakes occur in sandhills, scrub, high pine and turkey oak woodlands, hardwood hammocks, dry river floodplains, and areas near temporary wetlands. Adults and juveniles of this species can be found in suburban neighborhoods where development encroaches into favorable habitats.
Southern Hog-nosed Snakes are renowned for their elaborate “death feigning” defensive behavior. When threatened, a snake will flatten its head and neck and hiss loudly. It may strike, but only as a bluff with its mouth closed. If it is further harassed, it will flip onto its back and convulse for a short period and may defecate, expel foul-smelling musk from two glands in the base of the tail, and regurgitate its food. It will then remain motionless with its belly up, mouth open, and tongue hanging out. It may play dead for several minutes before cautiously turning over and crawling away. Southern Hog-nosed Snakes appear to be less inclined to use the death feigning behavior than Eastern Hog-nosed Snakes (Heterodon platirhinos). When threatened, it is not uncommon for these snakes to only flatten their head and necks, hiss loudly, and hide their heads beneath coils of the body.
Southern Hog-nosed Snakes feed primarily on frogs and toads, which they often excavate from the ground using their upturned snout like a spade. However, they will also eat small lizards and small mammals. Southern Hog-nosed Snakes are not constrictors but rather subdue their prey using a mild venom.
In Florida, females typically lay 6-19 eggs, which hatch between September and October after incubating for about 60 days. Hatchlings are about 5-7 inches (13-18 cm) in total length.
The genus name Heterodon means “different tooth,” which refers to the presence of enlarged teeth on the rear of the upper jaw. These enlarged teeth inject a mild venom into prey, and they also serve to pop inflated toads like a balloon to enable easier swallowing.
The defensive behaviors of flattening the head and hissing when frightened have given rise to several colorful local names used by native Floridians, such as puff adder and spreading adder. In truth, however, these snakes are not adders.
Another old myth states that southern hog-nosed snakes can kill a person from twenty-five feet away by mixing venom with their breath. This myth is completely false, and their breath is harmless.
County data coming soon.
If you have a new or interesting observation for this species, please email the herpetology staff at the Florida Museum.
Ernst, C.H. and E.M. Ernst. 2003. Snakes of the United States and Canada. Smithsonian Institution Press, Washington, DC. 668 pp.
Krysko, K.L., K.M. Enge, and P.E. Moler. 2019. Amphibians and Reptiles of Florida. University of Florida Press, Gainesville, Florida. 706 pp.
Powell, R., R. Conant, and J.T. Collins. 2016. Peterson Field Guide to Reptiles and Amphibians of Southern and Central North America. Fourth edition. Houghton Mifflin Harcourt Publishing Company, Boston and New York. xiv + 494 pp.
Share your observations
You can help scientists better understand the biology and distribution of this species by sharing your observations. Send photos or videos of interesting observations, along with associated information, by emailing the herpetology staff at the Florida Museum for documentation in the Museum’s Herpetology Master Database. You can also post your observations on iNaturalist.
Additional helpful information
Do you have snakes around your house? Learn how to safely co-exist with snakes.
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