Eastern Box Turtle Terrapene carolina Fayetteville, Georgia Natural Area

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2 Eastern Box Turtle Terrapene carolina Fayetteville, Georgia Natural Area Re-population of area cleared for agriculture/ Compared to adjacent natural area. By: Dennis E. Chase October 2011 Abstract: Introduction: Interest in gathering information related to the Eastern Box Turtle began in early 2007 during initial investigations of the a 300-acre property that the city of Fayetteville, Georgia, had recently acquired. City officials requested information on the potential nature area values or other use(s) of this property. The city of Fayetteville owns the property from the East side of Whitewater Creek to approximately 100 meters to the East of Ginger Cake Creek. The North side of the property is bounded by a gravel road and pipeline that connects a drinking water pumping station near Whitewater Creek, over a ridge and across Ginger Cake Creek in an West-East direction. The South end of the property abuts a private property line upstream from the point of confluence for Ginger Cake Creek and Whitewater Creek. The property totals approximately 304 acres. Adjacent properties are mostly in natural conditions along Whitewater Creek where homeowner associations own 45 acres which, together with other private property provides a West buffer. A local developer owns the 19-acre segment at the Southern end of the property. The East side abuts a landfill and several commercial properties. Of this total area, data from turtles have been collected primarily along Whitewater Creek and Ginger Cake Creeks in the Northern-most 150 acre segment of the property. During the on-site visits to evaluate resource values, I came upon what I believed to be significant numbers of Easter Box Turtles. Initially, photographs were used to identify individual turtles and later this information was augmented by numbered tags and GPS coordinates. In 2008, I applied for and received a State of Georgia Scientific Collector permit to allow more detailed measurements of these turtles. Based on my fish and wildlife background I anticipated that a study of the turtle populations for the entire area would provide valuable basic information on the overall resource values. Logically, the previously farmed areas should have lower population levels when compared to the adjacent less-disturbed wetlands and upland hillsides. Tarasan and Delis, 2007, found no turtles in agricultural subarea as opposed to 40 in natural habitat, so it was reasonable to expect lower populations along Ginger Cake Creek and other previously farmed areas of this nature area.

3 Ginger Cake Creek on the East side of the property was realigned, probably in the mid-1930's and is clearly visible (Photos XXX) as a straight tree-lined stream with open farmland on both sides. This condition has carried over to current conditions as an impacted stream with bank erosion (5-foot vertical banks) with virtually no vegetation. In several areas, there is significant undercutting of trees along the banks. There are indications that the stream is beginning to recreate meanders but the process will take many years to reach stable conditions. Due to very high energy water flows, most of the creek substrate has washed away leaving hard clay bottom which provides very limited benthic habitat. As the creek nears it s confluence with Whitewater Creek at the South end of the property, the floodplain is closer to natural and the bank erosion is much reduced with streambanks of 1 to 2 feet. The floodplain on both sides is very flat with little variation of habitats. Whitewater Creek boarders the West side of the city property and has many areas of the floodplain which is characterized by closed canopy conditions. There are numerous specimen trees, many well over 100 feet in height. The stream has wide meanders with mostly sloping banks and only moderate bank erosion. However, there is a high level of sediment in the stream bottom being transported from upstream areas. The floodplain is crossed in several locations with old stream oxbows and/or drainage channels from the upland areas. The upland areas have numerous erosion channels, probably a result of early farming practices. Materials and Methods Appendix A contains aerial photographs, beginning with Agricultural Stabilization and Conservation Service (ASCS) series from 1942, 1949, 1958, 1965 and 1972 which show the progression of this property. A recent aerial photograph (approximate 2008) shows the current conditions. The population evaluation was conducted by visual searches, often including student volunteers. On-site visits usually lasted two and sometimes as many as four hours of searching likely turtle habitat. The 2011 study included radio-tracking one male and one female turtle in each segment. Often, tracking these turtles led searchers to turtle use areas where other marked and unmarked turtles were often found. About 32 to 35 location records were taken for each of the four turtles during the months of May through early October. All additional new turtle captures were measured and marked as well as recorded data from any earlier captures. A group of six students and one of the biology teachers from Fayette County High School participated in this study. Each participant received a short training exercise with the transmitters, receiving device and a hand-held GPS recording instrument. All participants were included within my Georgia Scientific Collector s Permit as sub-permit holders. The project began on April 30, 2011, when four adult turtles were located, and affixed with small transmitters. The transmitters were placed so there should be minimal interference with turtle movement. Each turtle was measured and tagged (if not already marked) and released to the exact location where the turtles were found.

4 The transmitters are supplied by Wildlife Materials, Inc., type - SOPR-2190, 2-stage multivibrator operating at thru MHz. Each with a range of 150 Meters in the forest habitats under consideration. Signal reception was a Wildlife Materials, Inc., receiver Model TRX-16S and a YAGI antenna. GPS coordinates were taken by a GARMIN GPSmap 76Cx and data downloaded to computer via cable. One male and one female turtle from each of the sub-areas had transmitters attached and during the period of May to late October, each of the turtles were tracked and GPS locations were recorded and downloaded to a computer mapping program. The six students spent approximately 1.5 hours per visit and made over 30 trips to the area - a significant contribution of time by volunteers. Results: Entering this study, there was an expectation that the turtle population would be smaller both in numbers and in size for the Ginger Cake Creek sub-area because of the intense agricultural practices prior to Investigations in other parts of the country have suggested that turtle-use of intensely farmed areas would limit the eastern box turtle populations. Several of these studies also suggested that repopulation of intensely farmed areas is a very long, if ever, consideration. Therefore, the 50-year interval since farming ceased on the property should limit the overall numbers and expansion of turtle use of these areas. Any turtles would probably be transients and re-establishing a viable population would take many years. If repopulation was taking place, then the turtles using the area should be smaller turtles overall. There were several instances of marked turtles moving between the two sub-areas of the total study acreage. Therefore the populations can be considered together producing a male to female ratio of very close to even, males being only slightly higher. Table 1 is the summary data for the turtles - center lengths - measured over the course of the study. Male turtles range was cm to 9.40 cm for the Whitewater Creek sub-area and cm to 8.03 cm for the Ginger Cake Creek sub-area. Female turtles range was cm to 6.09 cm for the Whitewater Creek sub-area and cm to 3.56 cm for the Ginger Cake Creek sub-area. As can be seen from the data presented above and in table 1, the populations are similar in size, sex ratio and center length sizes. The four largest male turtles were captured in the undisturbed areas of Whitewater Creek. However the largest female turtle was captured was in the Ginger Cake Creek sub-area (along a heavily wooded steep slope that had not been cleared for agriculture). Table 1 Center Length (cm) Whitewater Creek Ginger Cake Creek M F M F Average Median

5 The average length of males, is slightly greater than females for both sub-areas. These results are similar to other studies that have reported this characteristic. Using 10.0 cm as the upper size limit for juveniles, (Miller, Mack & Mook, 2007) the population breaks down to 91.7percent adult and 8.3 percent juvenile. This compares favorably to the referenced population dynamics of 94 percent to 6 percent. This suggests that a reasonable level of recruitment to the population is taking place. From the juvenile population, seven were judged to be yearlings and, in one case at 3.5 cm, a just hatched turtle. The total number of turtles recorded for each segment are: 77 males and 67 females for Whitewater Creek and 71 males and 75 females for Ginger Cake Creeks respectively. That equates to 5.5 turtles per ha for Whitewater Creek and 7.3 turtles per ha for Ginger Cake Creeks (within the study subareas). Composite total for the study area is 6.3 turtles per ha. From this group, there were only two instances of mortality from the marked turtle populations. One male and one female, both from the Whitewater Creek portion of the study area were lost. Causes of the mortality was unknown. This moderate population level of 6.3 per ha indications that the turtle population is stable or in a near-stable condition. The loss of two marked turtles indicates that there is some mortality taking place among adult turtles, but probably within levels which would maintain a stable population for this area. Discussion: Among the natural amenities of this area which makes the property especially unique is that a large portion of the central and Eastern portions were intensively farmed up until the mid 1960's. Exactly what was under cultivation is not known at this time. However animal pens and barbed wire fencing indicate that some segments were used for animal pasture. After the farming operation creased, sometime in the mid 1960's, the fallow fields entered early stages of succession. Currently almost all of the farmed area has forest cover of different ages and species makeup. The exceptions are small grassy areas along the dirt road that serviced the farmstead. Most of the turtle research efforts took place on areas along the two creeks in smaller segments within the property owned by the city of Fayetteville. From the top of the ridge line between the two creeks, there is approximately 26 ha in the Whitewater Creek portion and from the ridge top to the East, there is approximately 20 ha in the Ginger Cake Creek segments. Both segments contain habitats that are more-or-less undisturbed as well as heavily farmed acreage. A number of other dead turtles have been found during the course of the 4-year investigation. None of the shells have evidence of animal damage. Some have pockmarks from bacteria damage to the shell surfaces but none that penetrate the shell. Only a small number of the turtles captured had tooth marks or other evidence of exterior damage. This compares favorably with populations near roads where many of the remaining turtles have evidence of significant shell damage, most likely from automobile impacts.

6 This year, none of the turtles showed any evidence of stress from poor health. This compares to the previous year where two individuals had eyes shut from mucus excretions or were simply lethargic and unresponsive to the presence of investigators. One female turtle was found with recent shell damage, most likely from an off-road vehicle tracking through an opening in a previously farmed area. Off-road vehicles are prohibited throughout the 300-acre natural area, so this should be a rare incident. The top of her shell had been punctured, leaving a 2 cm hole that had evidence of a small amount of bleeding. This turtle was treated with antibiotic and the hole filled with a permanent material and after a short rehabilitation period release back to the exact location where she was found. Followup searches have not located her, either alive or dead. Turtles were observed eating a wide variety of food. At one location, a turtle was observed eating carrion fish in a recently dried backwater of Whitewater Creek. More commonly, food consisted of mushrooms and berries. Red mulberry and black cherry tree fruit were noted as well as the use of blackberry thickets. The emphasis for this year s effort centered on tracking four Eastern Box Turtles which had small radio transmitters attached. The effort was to try to identify home range use of the various ecosystems that exist on this property with special attention to use of the previously farmed acreage. A big part of this was to engage high school students throughout the Spring and Summer months when the turtles were most active. In addition to the educational value, the increase in public exposure for protecting the natural area and to protecting the Eastern Box Turtle was enhanced. Three of the tracked turtles had moderate size home ranges, at least as represented by the part-year study. The Whitewater Creek male stayed within an area of approximately.6 ha; the Whitewater Creek Female s range was somewhat larger at 1.1ha. The Ginger Cake Creek male stayed within an area of approximately 1.5 ha while the female from the Ginger Cake Creek sub-area was an aberration and included parts of both sub-areas totaling just over 16.2 ha. Swarth and Quinlan, 2007 found home ranges of 6.2 ha for females and 1.2 ha for males. The variation by turtles in this study, when compared to other referenced home range data is not obvious at this time. Female number 5 took two long and difficult trips from one side of the study area to the other. When she was first fitted with the transmitter, she stayed on the Ginger Creek floodplain, part of the previously farmed area. Then, she crossed Ginger Cake Creek at one of the most difficult locations possible. The creek banks at that location are undergoing significant erosion and has banks with very little vegetation and a near-vertical drop of about 2 meters on both sides. She was able to climb up and proceeded due East in a near straight line to the edge of the wetland area into the edge of an active landfill. She was located within an extremely dense stand of blackberry vines, sweetgum saplings and thick layers of other vines. Because she had left the natural area and was within a construction fill site, she was considered to be in danger. A decision was made to return her to her original location. From there, she immediately traveled due West up a steep wooded ridge (a rise of 20 meters) and then traveled Southwest 850 Meters to the edge of a beaver swamp where she stayed for about a week. This is well within the Whitewater Creek sub-area.

7 After a few days, she turned back Northeast to the general area where she started, though she now stayed mostly on the Ginger Cake Creek side of the ridge. The span from her Easterly-most to Westerly- most locations was over 1,400 meters. In the process of her movements she went through 5 or 6 different ecosystems and back. Table 2 Measured movements (Meters) Whitewater Creek Ginger Cake Creek # 3 - Male # 9 - Male Total distance moved - 1,457 Total distance moved - 1,930 Ave. Per day = 9M Ave. Per day = 12M # 7 - Female # 5 - Female Total distance moved - 2,461 Total distance moved - 2,630 Ave. Per day = 15M Ave. per day = 16M On average, the females moved further than the males. There was no apparent purpose for the female movements, but for the males, move were between what appeared to be favored feeding locations. It is not reasonable, based on this limited data to conclude that the females are more active over their areas, but this is a consideration. Ecosystems use: Overall, Eastern Box Turtle use of the entire 300-acre nature area is very widespread. The exception is a 27-acre (11 ha) area located on the highest portion that was intensively farmed. This area is also much dryer throughout the year. It contains a mixture of loblolly pine, sweetgum. water oak and dense stands of crabapple trees. There is moderate under story and ground cover but not much habitat for the turtles to use for short-term resting where they are hidden from view. The more common pine is also less preferable for turtle use - though finding turtles in dense mats of pine needles is difficult and could skew the frequency of turtle locations. Turtle #3 - male. This turtle, located in the Whitewater Creek sub-area, occupied the smallest home-range and moved the least of the four turtles tracked. He made one long trip outside his normal range in late July through the first week of August. This was a visit to the edge of a beaver swamp which also receives numerous temporary visits from other turtles from throughout the nature area. The home range for turtle #3 is an old-age stand of mixed oak-hickory with a variety of other tree species such as red maple, ironwood and swamp chestnut oak. There is an old oxbow from Whitewater Creek which is deep enough to contain running water for part of the year and standing pools throughout the rest of the year except during extreme drought conditions. One portion is an up-slope that rises just out of the floodplain. A small stand of paw-paw (Asimina triloba) accounted for many location events during the Summer. This same paw-paw patch also attracted

8 a number of other box turtles. Turtle #5 - female. By far the most active turtle spent most of her time within the Ginger Cake Creek sub-area. However, she too made a trip to the edge of the beaver swamp in the Whitewater Creek sub-area. This trip starting in mid-june and she didn t return to her home range until mid-july. This is a one-way movement of over 1,800 Meters. In late May, this same female had made a very difficult trip 600 Meters in the opposite direction to the edge of a construction-material landfill. She was returned to the original tagging location because she had left the nature area and due to the danger of her new location. This trip, while shorter, included crossing Ginger Cake Creek at a point where the stream bank was nearly vertical, a drop and subsequent climb of 2 Meters on each side. Overall, her range was over 3,000 Meters. A straight line between capture locations demonstrate that she went through several very different habitats. Her home range is a combination of the Ginger Cake Creek floodplain which is predominately red maple. The upland portion of her range is an old growth oak-hickory, steep-sloped area frequented by a large number of other turtles. To make the two trips outside her more confined home-range, she visited/crosse through: a stand of sycamore, dense stands of sweetgum saplings mixed with blackberry and other dense vines, old agriculture fields of loblolly pine, crabapple, sweetgum and water oak, a closed-canopy swamp chestnut oak-willow oak floodplain forest, dense stands of lizard s tail and button bush and other mixed open swamp habitat and through very dry grass areas near the old farm road. Turtle #7 - female. This turtle had a medium-sized home range within the Whitewater Creek floodplain. Her movements overlapped that of male #3, though there was not evidence that these two turtles encountered one another. In late May to early June, she also made a trip outside her primary home range to the edge of the beaver swamp. Overall, her movements were within an area larger than other male turtles measured, but much smaller than #5. She also visited the pawpaw patch but with no evidence she was there at the same time as #3. Most of her time was in a closed-canopy oak-hickory floodplain predominated by swamp chestnut oak and pignut hickory. This area has a much more diverse variety of trees than other portions of the nature area. Turtle #9 - male. This turtle spent most of his time along the steep-sloped hardwood forest above Ginger Cake Creek. On one occasion, he crossed over the old farming road and slightly downslope into the Whitewater Creek drainage. However he did not stay long before returning to the Ginger Cake Creek sub-area. He also ventured, on several occasions East onto the flat bottomland area along Ginger Cake Creek. This bottomland area is predominately red maple with a scattering of ironwood trees. There is very little change on this floodplain as it was farmed and in pasture up until the mid 1960's. Ginger Cake Creek was straightened in the 1930's and all vegetation cleared to the edge of the creek bank with the exception of a few black willows and red maple trees. Many of these have fallen as the creek has begun to change back to a meandering stream and undercut the tree root systems. Turtle #9 spent a great deal of time in the vicinity of a red mulberry tree on the steep slope in the middle of his home range. A number of other turtles were often captured close to this tree as well indicating that it is an important food source for turtles.

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