Authored by Houston Chandler
Georgia is home to a diverse snake assemblage, but many native snake species are difficult to find unless one knows when and where to look. Many species are only active for a short time each year and are habitat specialists, rarely straying far from their preferred locations. These species are difficult to monitor and study because large amounts of survey effort are required to locate just a few individuals.
In mid-September, The Orianne Society began surveying for one of Georgia’s most elusive snakes—the Southern Hognose Snake (Heterodon simus). Southern Hognose Snakes are a small (adults generally range from 45–55 centimeters in total length), secretive species that are only active for a short time during the spring and fall of each year. They are close relatives to the more familiar Eastern Hognose Snake (H. platirhinos) but are rarely encountered because they are fossorial, spending the majority of the year underground.
Southern Hognose Snakes can be identified by their sharply-upturned snout (the species name simus means “snub-nosed”), uniformly-colored ventral scales and a single row of dark blotches along the dorsum. The upturned, pointy nose functions for more than just looks, as it is used to dig buried prey items out from underground. Southern Hognose Snakes feed primarily on anurans, especially toads, using their rear teeth to puncture inflated prey (making them easier to consume).
Historically, Southern Hognose Snakes ranged across much of the Coastal Plain of the southeastern United States, preferring habitats underlain by xeric, sandy soils that are well-drained. They can be found in sandhills, Longleaf Pine ecosystems and a variety of oak woodlands. Like most Coastal Plain species, Southern Hognose Snake populations are believed to be declining across much of their range, primarily because of habitat loss and degradation. Many populations likely persist in small habitat patches that are isolated from other populations by large expanses of unsuitable habitat. A small home range size combined with their fossorial nature makes isolated populations difficult to detect, highlighting the need to survey for this elusive species.
Because Southern Hognose Snakes are difficult to find, road cruising surveys through suitable habitat are often one of the most effective methods for sampling this species. We are conducting road cruising surveys at three locations in South Georgia from mid-September until the end of October—the time of year when Southern Hognose Snakes are most active. We hope to document this species at these locations and to begin to validate a species distribution model for Southern Hognose Snakes in Georgia that we produced in 2015.
Our first survey started on a cool, overcast morning. The cool weather was a promising sign that snakes would be active on the surface. To our surprise, it took less than five minutes to come across our first snake of the sampling season—a neonate Eastern Hognose Snake. Upon capture, this snake immediately displayed a characteristic hognose snake defensive behavior: flipping upside down and playing dead. That wasn’t enough to deter us from examining and measuring it (a whopping 20 cm. in total length). Unfortunately, this individual decided to take its defensive behavior a step further and regurgitated a recently consumed Southern Toad (Anaxyrus terrestris). We were encouraged by the fast start to our first survey, and by the end of the day, we had seen a large Eastern Ratsnake (Pantherophis alleghaniensis), a small Black Racer (Coluber constrictor) and a second neonate Eastern Hognose Snake.
Over the next two weeks, we successfully surveyed at all three sites and caught two more Eastern Hognose Snakes and an adult female Eastern Diamondback Rattlesnake (Crotalus adamanteus). These were promising results to start the survey season, but we still hadn’t seen a single Southern Hognose Snake. Little did we know that that was about to change. On October 4, we drove slowly down a sandy road when a snake-like shape appeared on the sand in the middle of the road. Even though it looked like a snake, we had been fooled by many sticks in the past. As we drove up to the mystery object, it became clear that this was in fact a snake, and a hognose at that! Adding to the excitement, this hognose turned out to be much more than the neonate Eastern Hognose Snakes that we had become accustomed to seeing. Sitting on the road beside the truck was a small, adult female Southern Hognose Snake (measuring just 38 cm.). Fortunately for this snake, we had come along at just the right time, as a car passed in the other direction soon after we moved her from the middle of the road.
We were excited to finally see a Southern Hognose Snake—only the second one that I had ever seen. After examining and measuring the snake, we sent her on her way in the direction that she had been traveling. We have three more weeks of road cruising surveys, and hopefully this was just the first of several Southern Hognose Snakes. However, the odds of finding more individuals are not in our favor. To date, we have completed 11 surveys at the three sampling sites and have seen a total of one Southern Hognose Snake, seven Eastern Hognose Snakes, two Black Racers (Coluber constrictor), one Eastern Ratsnake, one Eastern Diamondback Rattlesnake and two dead-on-road Timber Rattlesnakes.