Powdermill Nature Reserve


Walt MeshakaSnake Assemblage 

Since 2002, Walter E. Meshaka, Jr., PhD, Curator of Zoology/ Botany at the State Museum in Harrisburg, has been systematically marking and recapturing snakes that he finds under cover in three fields at Powdermill. How abundant each species is and where each is found is not known for Powdermill and poorly known for Pennsylvania in general. Through long-term study at Powdermill, he hopes to answer the question: what is the composition of the snake community? That is to say, how many of each species of snakes occurs at Powdermill? By knowing the answer to that question and knowing the life histories of each species, he can then answer the next logical question: why are snake communities at Powdermill structured as they are? That is to say, what is it about the habitat that results in the particular combination of species and their abundances?

To date, ten snake species have been reported from Powdermill. Of the six species he has found at Powdermill, the eastern garter snake is the dominant snake of the grassland habitat (68.5%). Although much less common, ringneck snakes are nonetheless seen throughout much of the active season (14.7%), whereas the redbelly snake (9.8%) and smooth green snake (4.4%) are seen most during June when females are full of young. Rat snakes are uncommon (1.6%), perhaps because of the thickness of the forest, and water snakes, not surprisingly, make a rare appearance (1.1%) as they travel between aquatic habitats.

Turtle Ecology 

turtle in net  

Begun at Powdermill in 1958 by Dr. Graham Netting, then-Director of Carnegie Museum of Natural History, individual mark-and-recapture research of two long-lived turtle species, the Eastern box turtle (Terrapene carolina) and the wood turtle (Clemmys insculpta), continues today under the direction of Powdermill Research Associate Dr. Walter Meshaka of the State Museum of Pennsylvania. Long-term study of both turtles at the same place—in this case near the northern and southern limits of their ranges, respectively—is exceedingly rare and provides the unique opportunity to answer questions regarding their growth, longevity, nesting, and seasonal movements. Such valuable data, in turn, provide the information necessary to manage populations of these long-lived, somewhat mysterious denizens of Pennsylvania forests. As part of his research at Powdermill, Dr. Meshaka has captured a snapping turtle which he extracts from a specially designed hoop net. In this image, he removes the 18-pound reptile which he will mark, record, and then release back into its home in Crisp Pond.


With approximately 450 records of total sightings during this long-term mark-recapture study, wood turtles outnumber box turtles two to one in both numbers marked and total numbers of sightings, but that overall trend has begun to reverse strongly in the past 10-15 years. Click here to see a preliminary summary of Powdermill’s long-term turtle data (1.0 Mb Acrobat PDF; if you do not have Adobe Acrobat Reader, click here for the free download).Comprehensive statistical analysis of the growth, abundance, and movement (home range) data is currently underway as part of a comparative study of the two species planned for publication in 2006.

The young lady with a turtle pictured here is Tricia Miller, our Netting Environmental Fund Intern in 2004, who worked directly on the turtle project under the direction of Dr. Meshaka and Powdermill’s Field Ornithology Projects Coordinator, Robert Mulvihill, who continued annual data collection for the study for a few years before and following Dr. Netting’s death in 1996 at the age of 92.