NC Museum herpetologist publishes rare history of even rarer snake
RALEIGH — For Jeff Beane, collection manager for herpetology at the North Carolina Museum of Natural Sciences, 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 current issue of the journal Copeia.
While most previous studies of these snakes have been limited to only a handful of observations, this study was based on 764 observations. By learning how to effectively find Southern Hognose Snakes, Beane and his co-authors were able to determine when they 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,” says Bryan Stuart, curator of herpetology for the Museum of Natural Sciences. “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, but, fortunately, the population appears to be currently stable in parts of the North Carolina Sandhills. This discovery underscores the necessity of protecting the Sandhills ecosystem if the Southern Hognose 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 North Carolina Sandhills relatively recently compared to other areas in the southeastern U.S., and that may explain why the Southern Hognose Snake has not yet declined in parts of the North Carolina Sandhills. Overall, this study provides a baseline for documenting future population changes of the Southern Hognose 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,” adds 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.”
An abstract of the paper follows.
Citation: Beane, Jeffrey C., Sean P. Graham, Thomas J. Thorp, and L. Todd Pusser. 2014. Natural history of the Southern Hognose Snake (Heterodon simus) in North Carolina, USA. Copeia 2014(1): 168-175.
Abstract: “The Southern Hognose Snake (Heterodon simus) is a poorly known and declining species in the southeastern U.S. We conducted road surveys from 1985–2012 and accumulated 764 observations of this species from the sandhills and southeastern Coastal Plain of North Carolina. Here, we report information on the size, sex ratio, diet, diel and seasonal activity patterns, and population trends of this rare species. Our results show that sexual dimorphism is biased toward larger females in this species, and that sex ratios are even in young size classes but become skewed toward males in adult size classes. Observations of this species peak during September–October, and most observations occurred from late morning through early afternoon during this seasonal peak of activity. We observed this species in similar numbers for the past 28 years, and no historical trend in our encounter rates was discernible. Recorded dietary items were made up almost entirely of the lizard Aspidoscelis sexlineata and the anuran Scaphiopus holbrookii. This study fills important gaps in our understanding of this rare species, provides an important baseline useful for future researchers or researchers in other regions, and provides information useful for developing effective management strategies and search protocols for H. simus.”