Movement Patterns and Microhabitat of Red-Backed Salamanders (Plethodon cinereus) Introduction Studying movements and microhabitat of a common, widespread

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  • Movement Patterns and Microhabitat of Red-Backed Salamanders (Plethodon cinereus) Introduction Studying movements and microhabitat of a common, widespread amphibian species such as Plethodon cinereus can identify abiotic factors. This information can be used to create better management plans to effectively protect habitat for amphibian communities (Welsh and Droege 2001). Soil temperature and moisture may affect movement of P. cinereus because they are ectoderms and their skin must be moist to allow for respiration. Radio tracking techniques can be impractical to study movement of smaller amphibians because transmitters inhibit the animals movement or cause trauma when the transmitter is surgically implanted. Tracking by fluorescent powder pigments is a less invasive way to acquire information about movements and usage of available resources (Eggert 2002). There has been no previous studies in Central PA using fluorescent pigment to analyze P. cinereus movement over a short 24-48 hour period and how microhabitat factors affect seasonal movement. Plethodon cinereus are found all year under cover objects (logs, rocks, etc.) in the eastern United States and have an average length of 7.8cm. Methods Comparing microhabitat of salamander locations to random locations Random Site Selection All sites were mapped using Google Earth. Four 50m x 5m transects were mapped. Coin flips determined random area points and transect direction. Samples were collected in June 2012. Every 10 m, soil and pH samples were taken. Results Conclusions Soil moisture was higher at salamander sites compared to random site. Surface and 5cm soil temperature were significantly lower at salamander sites. Soil moisture and temperature may play a role in how far P. cinereus move in a 24-48 hour period. Difference in soil moisture and temperature may explain differences in movement between seasons. Acknowledgements I would like to thank Dr. B. Hagerty for all of her support and guidance throughout this project. I also want to thank S. Chouljian and K. Ilgenfritz for assisting in field work. Cindy Sequeira Department of Biological Sciences, York College of Pennsylvania Hypotheses H 0 : There is no difference in microhabitat characteristics (pH, soil moisture, surface, and 5cm deep temperature) between random sites and P. cinereus habitat sites. H 0 : Microhabitat characteristics do not affect the total distance traveled by P. cinereus. References Eggert, C. 2002. Use of fluorescent pigments and implantable transmitters to track a fossorial toad, Pelobates Fuscus. Herpetological Journal. 12:69-74. Welsh, H.H. Jr. and Droege, S. 2001. A case for using plethodontid salamanders for monitoring biodiversity and ecosystem integrity of north american forests. Conservation Biology. 15:558-569. Cover Objects Searched Salamander measured, powdered and released beside cover object Trails followed using black light after 24 or 48 hours String marked trail and measured (cm) Major changes in direction (>90) marked with tape Future Studies Safety of using an oil to make the pigment last longer. This technique could provide additional movement information. Soil pH of two populations of P. cinereus or why pH may be physiologically important. Compare soil pH of two different populations of P. cinereus. Microhabitat factors throughout seasons Satellite view of study site in New Salem, PA. Microhabitat Characteristics Salamander site collection occurred during powdering. The same habitat data were used to compare random and salamander sites. Tracking Salamander Movement Captured April and June of 2012 Figure 1. Map of study site. RRT indicates random transect areas. PlCi indicates location of salamander. Google Earth. Measuring body length of P. cinereus Habitat Characteristic Random Sites Different than Salamander Sites? Direction of Difference pHNo, (t 31 =0.29, p =0.76) Similar in both sites Temperature (Surface) Yes, (t 31 =10.51, p < 0.0001) Lower at Salamander sites Soil moistureNo, (t 31 =1.578, p= 0.1247) Higher at Salamander Sites Random sites were warmer and drier than salamander sites Microhabitat Differences Dipping P. cinereus in Fluorescent powder P. cinereus Movement Microhabitat Characteristic Spring Different from Summer? Direction of Difference Soil MoistureYes, (t 7 =3.315, p= 0.0129) Higher in Spring Temperature (Surface) Yes, (t 7 =5.629, p= 0.0008) Lower in Spring P. cinereus moves shorter distances in the summer Typical string trail of P. cinereus Example of a fluorescent powder trail of P. cinereus