Habitat Use of Resident and Relocated Eastern Box Turtles

Steven J. Price, Joy M. Hester, and Michael E. Dorcas

Knowledge of habitat use is vital to understanding the effects of management strategies on animal populations. The relocation of box turtles from degraded sites to natural areas is a management strategy often proposed to mitigate the impacts of habitat destruction on box turtle populations; however few studies have examined how relocated turtles use habitat in comparison to resident turtles. From May 2004 to June 2005, we used radio-telemetry to examine macrohabitat and microhabitat use of 10 resident and 10 relocated female eastern box turtles on the Davidson College Ecological Preserve, an 89-ha natural area characterized by mixed forest and old fields bisected by dirt paths and power-line corridors. We found that both relocated and resident turtles preferred forested habitat over other habitat types, however inter-individual differences were evident. Additionally, both relocated and resident turtles were found closer to dirt roads and power-line corridors than expected, suggesting the preference of edge habitat. Our results suggest that relocated and resident turtles select for habitat in a similar manner. However, the presence of appropriate habitat into which turtles are being released does not assure relocation success, as our previous research has demonstrated that relocated turtles had higher mortality and disappearance rates than resident turtles.

The Effects of Urbanization on Stream Salamanders: Initiation of a Landscape-Level Experiment

Kristen K. Cecala, Steven J. Price, and Michael E. Dorcas

The Charlotte, NC metropolitan area contains one of the nation’s fastest growing human populations and urban sprawl is quickly expanding into the Piedmont forested lands. Amphibians are particularly vulnerable to landscape-scale habitat destruction, especially when roads, neighborhoods, and shopping centers dissect and degrade previously intact habitat. Previous research showed that stream salamander abundance was negatively correlated to the percentage of disturbed (e.g., urban) land within watersheds of first-order streams; however the proximate mechanisms resulting in this reduced abundance are unknown. Therefore, we are performing a multi-year, landscape-scale experiment in the Charlotte metropolitain area to: 1) investigate how the relative abundance of stream salamanders change as stream watersheds undergo urbanization, 2) examine the ability of adult salamanders to persist in disturbed stream habitats and, 3) explore other sub-lethal stressors that impact salamanders in urbanized watersheds. Currently, we have captured over 2,100 salamanders of 6 different species, including Desmognathus fuscus, Eurycea cirrigera, Eurycea guttolineata, Gyrinophilus porphyriticus, Pseudotriton montanus, and Pseudotriton ruber and have used visible fluorescent implant elasomers to uniquely mark 300 salamanders. Preliminary results of development on stream salamander populations indicate that declines may have occurred, however future analyses are needed to clarify these findings. Additionally, we have found several D. fuscus heavily infested with parasites initially identified within the order Acari, which may be an important sub-lethal stressor on Piedmont salamander populations. We will continue to monitor salamander abundance and habitat condition during and after watershed development.

Comparative Water Loss and Rehydration in Three Species of Plethodontid Salamanders with Temperature Variation

Mackenzie Cowell, William Stoudemire, Steven J. Price, and Michael E. Dorcas

The preferred habitats of plethodontid salamanders in the western Piedmont of North Carolina range from completely terrestrial (white-spotted slimy salamander; Plethodon cylindraceus), to mostly aquatic (northern dusky salamander; Desmognathus fuscus).  The southern two-lined salamander (Eurycea cirrigera) is also aquatic, but ranges into terrestrial environments more commonly than D. fuscus.  We tested the hypothesis that more terrestrial species would have lower evaporative water-loss and higher rehydration rates than more aquatic species by comparing evaporative water loss in these species at 5°C, 15°C, and 25°C.  We found that P. cylindraceus had lower evaporative water-loss rates than the more aquatic forms.  However, D. fuscus had slightly lower evaporative water-loss rates than E. cirrigera (p<0.0001).  At 5°C and 15°C evaporative water-loss rates were similar within species, but rates increased at 25°C.  Rehydration rates (conducted at the same three temperatures as dehydration) were not significantly different between species (p>0.05), although they did increase with temperature.  Our results generally support our hypothesis that more aquatic species tend to lose water at higher rates and indicated all species experienced substantial water loss at 25°C (average water loss > 25% body weight).   However, explanations for a higher evaporative water-loss rate in E. cirrigera than in D. fuscus remain elusive.

Ecology of Turtles Inhabiting Golf Course and Farm Ponds in the Western Piedmont of North Carolina

Elisabeth L. Failey, John C. McCoy, Steven J. Price, and Michael E. Dorcas

Urbanization and land alteration are anthropogenic factors frequently associated with turtle population declines. Golf courses represent a prevalent form of land alteration in many areas, yet our understanding of reptile populations inhabiting golf courses is limited. We conducted a comparative ecology study of turtles inhabiting five golf course and five farm ponds in the western Piedmont of North Carolina from 17 April 2005 to the 28 July 2005. We assessed relative species richness, species abundances, size distributions, body condition and sex ratios between pond types. We also examine the effects of current surrounding habitat within a 500 m pond radius of each pond and pond size on painted turtle (Chrysemys picta), common snapping turtle (Chelydra serpentina), yellowbelly slider (Trachemys scripta) and eastern mud turtle (Kinosternon subrubrum) abundances. In total we captured 248 C. picta, 43 C. serpentina, 86 T. scripta, and 28 K. subrubrum. We captured more K. subrubrum when roads were located farther from ponds (P = 0.05), more C. picta in ponds with a higher percentage of surrounding unforested habitat (P < 0.05) and a greater number of C. serpentina and C. picta in larger ponds (P = 0.01 and P = 0.05, respectively). Relative species abundances, size distributions for each sex and sex ratios were not distinguishable between the two pond types, although C. picta from golf course ponds had higher condition indices than those from farm ponds (P < 0.001). Thus, it appears that both farm pond and golf course habitats provide habitat for several species of semi- aquatic turtles.

Activity, Growth, and Survivorship of Post-Metamorphic Fowler's Toads (Bufo fowleri) in Different Habitats

Chad A. Jennison*, Shannon E. Pittman, Steven J. Price, and Michael E. Dorcas

* The University of Georgia

The conversion of forested land to agricultural or urban land may have significant affects on the amphibian populations. Additionally, edge effects, such as increased soil and air temperature and decreased humidity, may extend considerable distances into undeveloped forest and impact amphibians living in habitat edges. Our objective was to determine the effect of habitat alteration on the activity, growth, and survivorship of Fowler’s toads (Bufo fowleri). We constructed a set of three 2X2 enclosures in four different habitats: 15m from the edge into the field, at the edge forest-field interface, and 15m and 30m into a forest. We seeded each enclosure with 20 recently metamorphosed B. fowleri and measured activity, growth and survivorship over a three-week period by pitfall trapping within the enclosures. We found that activity in the field was lower than in the other habitat types (p < 0.05), and that activity decreased over time in all habitats (p < 0.01). Growth was most rapid in the edge, followed by both forest plots and then the field. Survivorship decreased in all habitats during the study period (p < 0.05) however, fewer toads survived in the field than in the edge or forested habitats (p < 0.05). These results suggest that juvenile Fowler’s toads are sensitive to cleared habitat, which provides very little refuge from heat or desiccation. Conversely, edge habitat appears to be suitable for toads, which may explain their ubiquity in suburban and urbanized regions of the southeastern United States.

Predictors of Winter Anuran Calling Activity in the North Carolina Piedmont

Michelle S. Kirlin, Michelle M. Gooch, Steven J. Price, and Michael E. Dorcas

An Assessment of Leech Parasitism on Semi-Aquatic Turtles in the Western Piedmont of North Carolina

John C. McCoy, Elisabeth L. Failey, Steven J. Price, and Michael E. Dorcas

During the summer of 2005, we assessed the occurrence of leeches on semi-aquatic turtles in five farm ponds and four golf course ponds in the western Piedmont of North Carolina.  Placobdella parasitica was the only species of leech found to parasitize turtles and was present on turtles from all study ponds.  Female painted turtles (Chrysemys picta) were more frequently parasitized than males (females 54.7%, males 40.9%; p= 0.039), possibly because they are larger and provide more surface on which leeches can attach.  Common snapping turtles (Chelydra serpentina) had the highest leech load of any species (mean = 32.3 per turtle) which we attribute to its relatively large size, reduced plastron size and bottom-dwelling habits.  We found no relationship between the parasite load and body condition of turtles.  Overall, there were no differences in mean leech load between the two pond types.  However, C. serpentina were parasitized more heavily in farm ponds (p < 0.001) while C. picta were parasitized more heavily in golf course ponds (p = 0.02).  Most leeches were found attached to the underside of the marginal scutes or between the plastron and inguinal region.  These sites most likely offer the most protection from the environment when the turtle emerges from the water.  

The Catawba River Corridor Coverboard Program: A Citizen Science Approach to Amphibian and Reptile Inventory

Shannon E. Pittman and Michael E. Dorcas

Coverboards are a useful inventory tool for many species of amphibians and reptiles and they provide a simple and effective method to involve the public in scientific research.  In 2003, the Davidson College Catawba River Corridor Program (CRCCP) was initiated to help coordinate the efforts of public and private sectors in surveying amphibians and reptiles.  Fourteen sites were established within the Catawba River Corridor in North and South Carolina. Participants included schools, private industry, and locally-operated nature preserves.  The Davidson College Herpetology Laboratory and Duke Power Environmental Laboratory helped set out coverboards at each site. The CRCCP website provided participants with assistance in species identification, protocols and online datasheets.  Between 2003 and 2005, a total of 38 species was documented, including 18 species of amphibians and 20 species of reptiles.  Coverboards proved more effective for inventory of salamanders and lizards (47% and 48%, respectively of within-range species), and less effective for anurans, snakes, and turtles (44%, 35%, and 24%, respectively of within-range species. The CRCCP provided the opportunity for many people, including numerous school children, to become involved in scientific research.  Although acceptance of species identification necessitates caution without voucher photographs, the program has added significantly to our knowledge of the distributions of amphibians and reptiles in the region.  Data collected through the CRCCP are essential to the development of effective monitoring programs and conservation measures.

Carphophis amoenus (DOR)

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