Inside NC Science: Rare history of a rarer snake

For Jeff Beane, the N.C. Museum of Natural Sciences’ collection manager of amphibians and reptiles, it all started with the discovery of a particular road-killed snake in 1985. Nine more such discoveries followed before he saw his first live southern hognose snake in the wild. Now, after 28 years and more than 750 documented run-ins with this secretive species, Beane has accomplished something equally elusive: the completion of one of the most thorough and long-term studies of a single snake species ever published.

Beane’s paper, “Natural history of the southern hognose snake (Heterodon simus) in North Carolina, USA,” appears in the June issue of the journal Copeia.

While most previous studies of these snakes in the wild have been limited to only a handful of sightings, this study was based on 764 observations taken through 2012. By learning how to effectively find southern hognose snakes, Beane and his co-authors were able to determine when the reptiles are active, in what habitats they occur, what they eat, how they reproduce and the proportions of youngsters, adults, males and females in a wild population.

“Two aspects of this study are particularly remarkable to me,” said Bryan Stuart, curator of herpetology for the museum. “First, snakes are notoriously difficult to find in the wild, yet Jeff and his co-authors were able to study the natural history of what may be the rarest and most threatened species of snake in North America. Second, they did so for 28 years! There are very few long-term studies on any snakes, anywhere. This tremendous effort by Jeff and his colleagues paid off.”

The authors show that the southern hognose snake has declined precipitously from much of its former range in North Carolina; fortunately, the population appears to be stable in parts of the Sandhills. This discovery underscores the necessity of protecting the Sandhills ecosystem if this species of snake is to persist in North Carolina.

The red imported fire ant has been implicated as a cause for the decline of the southern hognose snake elsewhere in its range. This invasive species of ant was introduced to the Sandhills relatively recently compared to other areas in the southeastern U.S., and that may explain why the southern hognose has not yet declined in parts of the Sandhills. Overall, Beane’s study provides a baseline for documenting future population changes of this snake as the invasive fire ant continues to negatively impact this ecosystem.

“The results of this paper are due to our very simple methodology of intensive, long-term survey efforts,” added Beane. “For species that are rare, secretive, seasonally active and otherwise difficult to survey for, those kinds of efforts might be the only thing that can produce meaningful results.”

Jonathan Pishney is communications director for the N.C. Museum of Natural Sciences.