RELOCATION AND POPULATION MODELLING FOR GOPHER TORTOISE RECOVERY ERIN CLARK. (Under Direction the of Robert J. Warren and J. Whitfield Gibbons)

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1 RELOCATION AND POPULATION MODELLING FOR GOPHER TORTOISE RECOVERY by ERIN CLARK (Under Direction the of Robert J. Warren and J. Whitfield Gibbons) ABSTRACT Because of its protected status and close association with the federally listed eastern indigo snake, the gopher tortoise has been the focus of a number of management strategies. Relocation has been one of the most controversial. Concerns about relocation stem from potential impacts on social structure, genetic mixing and spread of infectious disease. Most relocation efforts are not revisited to conduct long-term success monitoring.. This study monitored movement and home range of a relocated tortoise population in Aiken County, South Carolina. A small population from McIntosh County, Georgia was trapped and moved to the Savannah River Site, separated into experimental groups, and then penned for varying lengths of time in 1ha enclosures. Movement interaction of all groups was monitored over the course of one active season. The immediately released group showed the highest rate of dispersal, while the group with the longest period of penning prior to release showed the lowest rate of dispersal and the highest level of interaction post-relocation. Interaction appears to be pivotal to success of relocation in this species and penning may improve interaction and reduce dispersal, however, further study is needed. INDEX WORDS: Gopherus polyphemus, longleaf-wiregrass community, sandhills, relocation, restoration, penning

2 RELOCATION AND POPULATION MODELLING FOR GOPHER TORTOISE RECOVERY by ERIN E. CLARK Bachelor of Science, University of Georgia, Warnell School of Forest Resources, 2000 A thesis submitted to the Graduate Faculty of The University of Georgia in Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE ATHENS, GEORGIA 2003

3 2004 Erin E. Clark All Rights Reserved

4 RELOCATION AND POPULATION MODELLING FOR GOPHER TORTOISE RECOVERY by ERIN E. CLARK Major Professors: Committee: Dr. Robert J. Warren/ Dr. J. Whitfield Gibbons Dr. John B. Carroll Dr. Steven B. Castleberry Electronic Version Approved: Maureen Grasso Dean of the Graduate School The University of Georgia May, 2004

5 iv DEDICATION I would like to dedicate this thesis to my family who has always been with me every step of the way.

6 v ACKNOWLEDGMENTS Finishing a graduate degree requires much more than field assistance, although that in itself is invaluable. I would never have gotten this far without the support and encouragement of my parents Les and Deborah Clark. They were the first to say, We will support you whatever you decide to do. Thank God they meant it. A project of this scope could not have been done alone. I would like to thank Kelly Clark who spent most of his summer helping me radio track. I d also like to thank John Nestor, Tracey Tuberville, Peri Mason, J.D. Willson, Dr. Kurt Buhlmann, Josh Clark, Jason Norman and Lucas Wilkinson for their assistance in the field, which was always more than assistance; it was always a good day s work. Thank you to Margaret Wead, Peggy Burkman and Teresa Carroll who helped transcribe and organize data and field notes. Thanks to all the women of the Herp Lab for their support, especially Judy Greene-McLeod and Ria Tsaliagos. I d like to thank my committee, Dr. Whit Gibbons, Dr. Robert Warren, Dr. Steven Castleberry and Dr. John Carroll for the countless talks and meetings to prepare for this study, but also for their understanding, words of encourage and guidance throughout. Discovery of this population can be attributed to Leslie Clark who understood his daughter s commitment to wildlife and more importantly, supported it. The first phase of the project could not have been completed without the commitment of Bobby Moulis, Tracey Tuberville, Kurt Buhlmann, Josh Clark and Kelly Clark. I d like to thank state agency biologists John Jensen and Steve Bennett for helping us to make the project happen and McIntosh County officials and personnel for allowing us access and assistance. We

7 vi appreciate the assistance of Georgia Power, its subcontractors and landowners in and around the area of the population prior to relocation. The second phase of the project was completed with the help of many people, especially that of the U.S. Forest Service on the Savannah River Site (SRS). Mr. Pete Johnston, Dr. Don Imm and Mr. Paul Champlin in particular provided valuable input, field assistance, technical guidance in site selection and financial backing during the second phase. The U.S. Forest Service on the SRS will continue to provide management of the forests and compartments around this population ensuring their protection for decades to come. This project was supported by the Department of Energy through the University of Georgia Research Foundation, a student grant from the Gopher Tortoise Council and a grant from the South Carolina Department of Natural Resources. Funding was provided to purchase equipment and supplies from the U.S. Forest Service and Conservation International. Support for my graduate education was also derived from work completed under the Student Career Experience Program of the U.S. Fish and Wildlife Service. Finally, I wish to extend my appreciation to the many people who took the time to visit the release area and provide valuable perspective on the study, among these were Dr. Peter Pritchard, Dr. Michael Dorcas, Dr. Peter Paul Van Dyke, Steve Bennett, John Jensen and many others. Thanks to Dr. Ray Semlitsch and Dr. John Carroll, Dr. Steven Castleberry, Dr. Greg Masson, Dr. Whit Gibbons, Dr. Robert Cooper and Kelly and Josh Clark for help with experimental design. My sincere appreciation to Dr. Robert Warren who has proven not only an excellent advisor, but a great friend throughout my professional career. I d like to thank Dr.

8 vii Greg Masson (for getting me into herpetology) and the Georgia Ecological Services Office of the U.S. Fish and Wildlife for their continued support and encouragement throughout my educational experience. Finally, I d like to thank a dear friend who has become so much more, Lane Rivenbark. When you came into my life again, I had no idea how important you would become to me. Thank you for all of your support, understanding and motivation.

9 viii TABLE OF CONTENTS Page ACKNOWLEDGMENTS... v LIST OF TABLES... x LIST OF FIGURES... xi CHAPTER 1 INTRODUCTION, LITERATURE REVIEW AND THESIS FORMAT... 1 Introduction... 2 Justification... 2 Literature Review... 3 Thesis Format... 7 Literature Cited RELOCATION SUCCESS OF GOPHER TORTOISES: EFFECTS OF PENNING AND IMPLICATIONS TO CONSERVATION POLICY Introduction Methods Results Discussion Conservation and Policy Implications Literature Cited... 29

10 ix 3 PREDICTING POPULATION SURVIVAL OF A RELOCATED POPULATION OF GOPHER TORTOISE IN SOUTH CAROLINA Introduction Materials and Methods Results Discussion Literature Cited CONCLUSIONS AND MANAGEMENT IMPLICATIONS Conclusions and Management Implications Literature Cited Appendix A Appendix B... 66

11 x LIST OF TABLES Page Table 1.1: Dates of relocation and release, dispersal, and movements based on the entire season versus the first 45 days post-relocation for gopher tortoises, Savannah River Ecology Laboratory, Aiken, South Carolina, Table 3.1: Final population numbers predicted by the Leslie Matrix (population growth model)

12 xi LIST OF FIGURES Page Figure 1.1: The range of the gopher tortoise with reference to the location of the SRS, Compartment 24 is shown as an inset on the upper right (Credit David Scott and Gopher Tortoise Council). March Figure 3.1: Kaplan-Meier survival curves for the treatment groups Figure 3.2: Population growth curve of Release Group I Figure 3.3: Population growth curve of Release Group II Figure 3.4: Population growth curve of Release Group III Figure 3.5: Population growth curve of entire population Figure 3.6: Age structure of the relocated population in 2001 (not including 31 hatchlings headstarted in the laboratory)

13 1 CHAPTER 1 INTRODUCTION, LITERATURE REVIEW AND THESIS FORMAT 1 Clark, E.E., T.D. Tuberville, J.W. Gibbons, K.A. Buhlmann and R.J. Warren. To be submitted to Journal of Wildlife Managmenty.

14 2 Introduction Listed as federally threatened in the western part of its range and state listed throughout its entire range, the gopher tortoise (Gopherus polyphemus) is thought to be in serious decline. Because of its protected status and close association with the federally listed indigo snake (Drymarchon corais couperi), the gopher tortoise has been the focus of a number of conservation and management strategies. Among these, relocation, particularly in the state of Florida, has been the most controversial. The controversy surrounding relocation stems from the apparent unknown impacts to social structure, genetic mixing, and spread of infectious disease. Additionally, most relocation efforts have not been revisited to conduct long-term success monitoring or dispersal analyses. Justification As part of an overall effort to restore the gopher tortoise to Aiken County, South Carolina and develop a useful protocol for gopher tortoise relocation, we developed a study to monitor movement of a tortoise population following relocation. A population was selected in McIntosh County, Georgia. We located a population in McIntosh County, Georgia which was under threat of development and included adults, juveniles, hatchlings, and nests. This population was trapped and moved to the Savannah River Site. The animals were separated into experimental groups by sex/age class and then random assignment to release groups. These release groups were penned for varying lengths of time in 1-ha enclosures. Movement and interaction of all groups were monitored during one active season to determine first year dispersal rates. Although the goal of the project was to develop a relocation protocol which improves success of relocated animals, an understanding of movement and interaction of all groups following release was integral to understanding the relative assimilation

15 3 to the relocation site, selection of habitat, and density changes following release. The rescue of this population and restoration of the animals to a historic portion of the range were considered primary goals of the overall project and resulted in acceptable changes to the methodology. Literature Review The gopher tortoise is a large, terrestrial turtle reaching approximately 23 to 28 cm in total length and weighing 3.6 to 4.5 kg (Landers et al. 1982). These animals dig burrows averaging about 4.5m in total length (Diemer 1986) and can house over 300 different species of invertebrates and vertebrates (Jackson and Milstrey 1989). The burrow protects the tortoise from extremes in temperature, desiccation and predation (Hallinan 1923; Hansen 1963; Auffenburg and Weaver 1969; Means 1982). The gopher tortoise is associated with well-drained sandy soils of the southeastern Coastal Plain from South Carolina to Louisiana, where they inhabit a variety of plant community types. They are found typically in longleaf pine (Pinus palustris)-turkey oak (Quercus laevis) habitat (Auffenburg and Franz 1982; Diemer 1986). This fire-adapted community historically burned at 5-10-year intervals, typically in the summer (Wharton 1978). Open understory is created by frequent fire, which is important to the life cycles of many understory species, including wiregrass (Aristida stricta), which is a staple of gopher tortoise diet (Wright 1982; Wahlenburg 1946; Garner and Landers 1981). Gopher tortoises are primarily herbivores, foraging on fleshy fruit, legumes and grasses when available. At times, however, they also ingest rocks, bone and carrion (Carr 1952; MacDonald and Mushinsky 1988; Wilson et al. 1997). Sexual maturity occurs at varying ages throughout the range (10-21years), but appears to reflect the length of the activity season and local conditions (Wilson et al. 1997). Mating has

16 4 been reported for both fall and spring, but apparently peaks in May and June (Landers et al. 1980; Iverson 1980). Although the range of the gopher tortoise is documented from South Carolina to Louisiana, until recently, populations in South Carolina were known only from Jasper and Hampton Counties (Wright 1982; Mann 1990). Historically, records of the tortoise demonstrate its presence in the region of the Savannah River Site (Whit Gibbons, pers comm.). More recently, observations of two individuals were recorded in 1995 and In 1991, a disjunct population was discovered in Aiken County, South Carolina (Clark et al. 2001). Now designated as the Aiken Gopher Tortoise Preserve, this declining population is thought to contain fewer than one dozen individuals and is currently the northern-most population in the range (Steve Bennett, South Carolina Department of Natural Resources, pers comm). This population is located on a turkey oak sandhill with a variety of grasses, including wiregrass. It has recently been planted in longleaf pine and subjected to controlled burning (Johnny Stowe, pers comm). Of all the management strategies used in tortoise conservation, translocation and relocation are probably the most controversial. Relocation has been associated with disruption of social structure (Landers 1981; Berry 1986), unnatural genetic mixing, and spread of disease (Diemer 1986; 1987). Further, Burke (1989) reported that follow-up studies, analysis and dissemination of associated results for relocation projects were lacking. Florida has been the subject of several papers regarding tortoise relocation efforts (Diemer and Moler 1982; Diemer 1987; Burke 1989; Diemer et al. 1989). Most states (e.g., Georgia, South Carolina) in the southeastern United States still do not employ large-scale relocation. The concern regarding spread of disease through relocation has focused on Upper Respiratory Tract Disease (URTD), first identified in desert tortoises (Fowler 1976; Snipes et al.

17 5 1980). This disease, caused by a bacterium (Mycoplasma), damages the mucosal and olfactory epithelium. The disease is spread through direct contact between gopher tortoises. Some tortoises appear to maintain the bacterium for years and suffer recurrence both annually and when under stress (McLaughlin 1998). Although effective treatment has occurred in controlled settings, treatment has not yet proven effective in wild populations. Some biologists have suggested that certain individuals can probably survive recurring infection (H. Mushinsky, G. Heinrich pers comm). Screening is recommended for this disease prior to relocation to areas already inhabited by healthy tortoises. Dispersal from relocation sites is common. Although tortoises have been known to move nearly 1 km, they generally move only short distances from their burrows (Wilson et al. 1997) and exhibit a well-defined home range (Ernst et al. 1994). The movement patterns of natural populations, although widely documented (Gibbons and Smith 1968; Gourley 1974; McRae et al. 1981; Diemer 1992; Wilson et al. 1994; Wilson et al. 1997), are not well documented for relocation efforts. In the majority of relocation efforts, monitoring has focused on the number of tortoises found on-site rather than stabilization of movement patterns and home range of relocated animals. In general, most relocation efforts have not monitored long-term success. In instances where relocation success has been monitored, most have conducted mark-recapture studies within 1-2 years of release. Berry (1986) provided information on movement of desert tortoises (G. agassizi) following relocation, but those results may have limited applicability for gopher tortoise management due to differences in home range size and habitat of the species. One approach that has been tested to improve success of relocations and lower dispersal rates is penning animals on-site after relocation (Burke 1989; Doonan 1986). Burke (1989) suggested that penning had no effect on dispersal or success of relocation in tortoise, although

18 6 the maximum time tortoises were penned for this study was 15 days. Another study penned tortoises for up to 77 days and achieved similar results (Doonan 1986). Apparently, Doonan s (1986) effort is the longest period of penning Gopherus polyphemus for which findings have been published. Definite gaps exist in the literature regarding the effects of tortoise relocation. Little work has been conducted to determine long-term response to penning; in fact, few studies have considered long-term penning to improve relocation success. Objectives The objectives of this study were to determine whether movement, dispersal patterns and site fidelity of two groups of tortoises penned for different periods would differ significantly from tortoises that were not penned and to determine if movement stabilizes following the first active season. Hypotheses H 1 : Tortoises relocated into pens will show lower rates of dispersal (following removal of pens) than those not relocated into pens. H 2 : Adult male tortoises in the immediate release group will show the highest rate of directional persistence and will make the longest moves from the release area. H 3 : Tortoise movement will stabilize in both sexes of adults from the groups of penned animals and will be exhibited by a defined home range, but adult males in the immediate release group will not exhibit a defined home range. Source Population and Study Area The source population is located on the McIntosh County Industrial Park property in McIntosh County, Georgia, approximately 1.5 km north of I-95 along Highway 251. This 99- acre mixed-use industrial park currently houses a seafood-packing operation, a mental health and

19 7 substance abuse rehabilitation facility, a county jail, a cable company building and a small concrete operation. It also provides space for utility stations and equipment. There are plans to place an animal control facility in the East Field, a clearcut area directly behind the jail. Tortoises were interspersed in numerous habitat types on the property. The habitat quality of this site is characterized as poor, and tortoises were found in several locations classified as atypical habitat for this species. Soils across the site are fine sand or loamy sand in texture. They are characterized as Lakeland, Klej or Ona soil types in the USDA Soil Survey for McIntosh County (NRCS Soil Survey). The release site on the Savannah River Site is located in Aiken County, South Carolina. The release area is situated between the confines of Upper Three Runs Creek on the east, Tinker Creek on the west and Highway 278 to the north. Compartment 24, where pens will be located is approximately 971 ha and is approximately 1.5 km from Highway 278. The stand is underlain predominantly by Lakeland sand. It is currently being managed for red-cockaded woodpeckers (Picoides borealis). The release site is characterized by mature longleaf and loblolly pine (Pinus taeda) with an understory of grasses and forbs. Recently, the U.S. Forest Service began wiregrass restoration in the stand. The Forest Service intends to continue the current management of this stand through a 100-year rotation. Currently the compartment is burned every 3-5 years. Thesis Format This thesis is written in manuscript format with chapters 2 and 3 being separate manuscripts. Chapter 1 is a literature review of tortoise biology and a general introduction to issues surrounding relocation. Chapter 2 provides information on the penning study conducted on a population of relocated gopher tortoises with emphasis on movement and behavior.

20 8 Chapter 3 describes a population model built using a Leslie matrix and incorporating information on survival and social interaction within the different treatment groups. Chapter 4 contains conclusions and management recommendations drawn from the penning study and the population growth model, as well as, information on the logistics of relocation, the roles of policy and economics, and areas in need of future study. Literature Cited Auffenburg, W., and R. Franz The status and distribution of the gopher tortoise (Gopherus polyphemus). Pages in R.B. Bury, editor. North American tortoises: conservation and ecology. U.S. Fish and Wildlife Research Report 12. Auffenburg, W. and W.G. Weaver, Jr Gopherus berlandieri in southeastern Texas. Bulletin of the Florida State Museum, Biological Sciences 13: Berry, K.H Desert tortoise (Gopherus agassizii) relocation: implications of social behavior and movements. Herpetologica 42: Burke, R.L Florida gopher tortoise relocation: overview and case study. Biological Conservation 48: Carr, A.F Handbook of Turtles. Cornell University Press, Ithaca, NY. 542pp. Clark, E.E., R.N. Tsaliagos and A. B. Pittmann Gopherus polyphemus. Herpetological Review 32:3, September Diemer, J.E The ecology and management of the gopher tortoise in the southeastern United States. Herpetologica 42: Diemer, J.E Tortoise relocation in Florida: solution or problem? Proceedings of the Desert Tortoise Council 1984:

21 9 Diemer, J.E Home range and movements of the tortoise Gopherus polyphemus in Northern Florida. Journal of Herpetology. 26(2): Diemer, J.E. and P.E. Moler Gopher tortoise response to site preparation in northern Florida. Proceedings of the Annual Conference of Southeastern Association of Fish and Wildlife Agencies 36: Diemer, J.E., D.R. Jackson, J.L. Landers, J.N. Layne, and D.A. Wood, editors Gopher tortoise relocation symposium proceedings. State of Florida Game and Fresh Water Fish Commission, Nongame Wildlife Program Technical Report 5. Doonan, T.J A demographic study of an isolated population of the gopher tortoise, Gopherus polyphemus; an assessment of a relocation procedure for tortoises. MS Thesis, University of Central Florida, Orlando, FL. Ernst, C.H., R.W. Barbour, and J.E. Lovich Turtles of the United States and Canada. Smithsonian Institution Press, Washington, D.C. Fowler, M.E Respiratory disease in captive tortoises. Proceedings of the Desert Tortoise Council 1976: Garner, J. and J. Landers Food and habitat of the gopher tortoise in southwestern Georgia. Proceedings of the Annual Conference of Southeastern Association of Fish and Wildlife Agencies 35: Gourley, E.V Orientation of the gopher tortoise Gopherus polyphemus. Animal Behavior 22: Hallinan, T Observations made in Duval County, northern Florida, on the gopher tortoise (Gopherus polyphemus). Copeia 1923: Hansen, K.L The burrow of the gopher tortoise. Quarterly Journal of the Florida

22 10 Academy of Science 26: Iverson, J.B The reproductive biology of Gopherus polyphemus (Chelonia, Testudinidae). American Midland Naturalist 103: Jackson, D.R. and E.G. Milstrey The fauna of gopher tortoise burrows. Pages in J.E. Diemer, D.R. Jackson, J.L. Landers, J.N. Layne, and D.A. Wood, editors Gopher tortoise relocation symposium proceedings. State of Florida Game and Fresh Water Fish Commission, Nongame Wildlife Program Technical Report 5. 99pp + appendices. Landers, J.L., Techniques for restocking gopher tortoise populations. The gopher tortoise: Distribution, ecology, and effects of forest management. Final Report to Georgia Department of Natural Resources. Landers, J.L., W.A. McRae, and J.A. Garner Reproduction of the gopher tortoises (Gopherus polyphemus) in southwestern Georgia. Herpetologica 36: Landers, J.L., W.A. McRae, and J.A. Garner Growth and maturity of the gopher tortoise in southwestern Georgia. Bulletin of the Florida State Museum, Biological Sciences 27: MacDonald, L.A. and H.R. Mushinsky Foraging ecology of the gopher tortoise, Gopherus polyphemus, in sandhill habitat. Herpetologica 44: Mann, T.M The status of Gopherus polyphemus in South Carolina in C.K. Dodd, Jr., R.E. Ashton, Jr., R. Franz, and E. Wester, editors. Proceedings of the 8 th Annual Meeting of the Gopher Tortoise Council, Florida Museum of Natural History, Gainesville, FL.

23 11 McLaughlin, G.S Upper Respiratory Tract Disease: An Update - January /6/01. McRae, W.A., J.L. Landers, and J.A. Garner Movement patterns and home range of the gopher tortoise. American Midlands Naturalist 106: Means, D.B Responses to winter burrow flooding of the gopher tortoise (Gopherus polyphemus Daudin). Herpetologica 38: Snipes, K.P., E.L Biberstein, and M.E. Fowler A Pasteurella sp. associated with respiratory disease in captive desert tortoises Gopherus agassizii. Journal of the American Veterinary Medical Association 177: Wahlenburg, W.G Longleaf pine. Charles Lathrop Park Forestry Foundation, Washington, D.C. Wharton, C.H The Natural Environments of Georgia. Georgia Department of Natural Resources. 227pp. Wilson, D.S., H.R. Mushinsky, and E.D. McCoy Home range, activity, and use of burrows by juvenile gopher tortoises in central Florida. Pages in R. B. Bury and D.J. Germano, editors. Biology of North American tortoises. National Biological Survey, Fish and Wildlife Research 13. Wilson, D.S., H.R. Mushinsky and R.A. Fischer Species profile: Gopher tortoise(gopherus polyphemus) on military installations in the southeastern United States. Technical Report SERDP-97-10, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS.

24 12 Wright, S The distribution and population biology of the gopher tortoise (Gopherus polyphemus) in South Carolina. M.S. Thesis, Clemson University, Clemson, South Carolina.

25 13 CHAPTER 2 RELOCATION SUCCESS OF GOPHER TORTOISES: EFFECTS OF PENNING AND IMPLICATIONS TO CONSERVATION POLICY 1 1 Clark, E.E., T.D. Tuberville, J.W. Gibbons, K.A. Buhlmann and R.J. Warren. To be submitted to Journal of Wildlife Managment.

26 14 Abstract The gopher tortoise is a long-lived, late-maturing species which requires active management (e.g., prescribed burning) for maintenance of suitable habitat. The objective of this study was to determine success (via improved site fidelity and social interaction) following relocation. Movement was monitored in a tortoise population relocated from McIntosh County, Georgia to Aiken County, South Carolina. Adults and juveniles were separated into 3 experimental groups, and then penned for varying lengths of time in 1-ha enclosures. Movement and dispersal of all groups were monitored during the first active season following relocation. Tortoises in the immediately released group showed the highest rate of dispersal (62.5%) and low levels of interaction among adults (25%), whereas tortoises in the second release group showed lower dispersal (32.5%), but no interaction among adults. Tortoises in the third release group showed the lowest rates of dispersal (0%) and the highest levels of interaction among adults post-relocation (50%). Settling behavior (e.g., establishment of a burrow, continued maintenance of the burrow, and initial interaction with nearby tortoises) following relocation may be integral to establishing long-term social restructuring among relocated tortoises. Penning may provide both the time to settle and the opportunity to provide for interaction that might facilitate long-term social connections on a release site. Consideration of social structure in the planning phases of a relocation effort may be crucial to their long-term success. Introduction The gopher tortoise is a large, terrestrial turtle reaching approximately 23 to 28 cm in total length and weighing approximately 3.6 to 4.5 kg (Landers et al. 1982). They dig burrows below the surface, which average about 4.5 m in total length (Diemer 1986) and can house over 300 different species of invertebrates and vertebrates (Jackson and Milstrey 1989). The burrow

27 15 protects the tortoise from extremes in temperature, desiccation, and predation (Hallinan 1923; Hansen 1963; Auffenburg and Weaver 1969; Means 1982). The gopher tortoise is associated with well-drained sandy soils of the southeastern Coastal Plain from South Carolina to Louisiana. Although they inhabit a variety of plant community types, they are associated with longleaf pine (Pinus palustris)-turkey oak (Quercus laevis) habitat (Auffenburg and Franz 1982; Diemer 1986; but see Breininger et al. 1994). This fire-adapted community historically burned at 5-10 year intervals, typically in summer (Wharton 1978). Fire, which maintains an open understory, is important in the life cycles of many species, including wiregrass (Aristida stricta), which is a staple of gopher tortoise diet (Wright 1982; Wahlenburg 1946; Garner and Landers 1981). Although the range of the gopher tortoise is documented from South Carolina to Louisiana, until recently, populations in South Carolina were documented only from Jasper and Hampton Counties (Wright 1982; Mann 1990). A disjunct population was discovered recently in Aiken County, South Carolina (Clark et al. 2001). Now designated as the Aiken Gopher Tortoise Preserve, this declining population is thought to contain less than one dozen individuals and is currently the northernmost population in the range (Clark et al. 2001). This population is located on a turkey oak (Quercus laevis) sandhill with a variety of grasses, including wiregrass. It has recently been planted in longleaf pine and is managed with prescribed fire. The tortoise is a valuable species for relocation study because of its dependence on social structure (Berry 1986), creation of burrows which provide habitat for other species (Jackson and Milstrey 1989), frequent interface with development, and because relocation has been considered unsuccessful despite its widespread use. Relocation of gopher tortoises has been associated with disruption of social structure (Landers 1981; Berry 1986), unnatural genetic mixing, and spread

28 16 of disease (Diemer 1986,1987). Further, Burke (1989) reported follow-up studies, analysis and dissemination of associated results for relocation projects were lacking. Florida has been the subject of several papers regarding tortoise relocation efforts (Diemer and Moler 1982; Diemer 1987; Burke 1989; Diemer et al. 1989). Other states (e.g., Georgia, South Carolina) in the southeastern United States still do not employ large-scale relocation. Emigration from relocation sites is common. In natural populations, tortoises have been known to move nearly 0.6 km, but in general move only short distances from their burrows (Wilson et al. 1997) and exhibit a well-defined home range (Ernst et al. 1994). Although the movement patterns of natural populations are widely documented (Gibbons and Smith 1968; Gourley 1974; McRae et al. 1981; Diemer 1992; Wilson et al. 1994, 1997), similar information is not well documented for relocation efforts. In the majority of relocation efforts the monitoring appears to focus on the number of tortoises found on-site rather than stabilization of movement patterns and home range of relocated animals. One approach that has been tested to improve relocation success and lower emigration rates is penning animals on-site after relocation (Lohoefener and Lohmeier 1986, Doonan 1986, Burke 1989, Knizley 1997). Lohoefener and Lohmeier (1986) reported improved site fidelity among tortoises that were penned, particularly those penned in groups, and recommended penning relocated tortoises for at least 1 week. Burke (1989) suggested that penning had no effect on emigration or success of relocation in tortoise, although the maximum time that tortoises were penned for this study was 15 days. Another study penned tortoises for up to 77 days and achieved similar results (Doonan 1986). Apparently, Doonan s (1986) effort is the longest period of penning Gopherus polyphemus for which findings have been published. However, Knizley (1997) conducted a penning study using approximately 19-km 2 enclosures for

29 17 periods of 3-15 months and found that tortoises remained in human-created densities following relocation (although the author notes that other factors besides penning probably contributed to this pattern, including development onsite that reduced undeveloped habitat by 75% and high biomass of herbaceous food plants at the relocation site). In the present study, the effectiveness of various penning lengths was evaluated and patterns of movement were monitored post-release. In addition, information recorded during the telemetry study allowed us to determine relative survival of tortoises in different treatment groups and the level of likely interaction among individuals, which allowed us to evaluate the likely contribution made by particular individuals to the breeding population. We expected tortoises relocated into pens to show lower rates of dispersal (following release from the pens) than those not relocated into pens. We further expected adult male tortoises in the immediately released group to show the highest rate of directional persistence and make the longest movement from the release area. Finally, we expected adult tortoise movements to stabilize in both sexes from the groups of penned animals (exhibited by a defined home range), but not in adult males in the immediately released group. Study Area Tortoises were relocated from the McIntosh County Industrial Park, a 40-ha industrial park with various types of development, as well as logging and utility maintenance activity, in McIntosh County, Georgia. Following relocation to the Savannah River Site (SRS), a 780-km 2 federal, nuclear materials processing facility near Aiken, South Carolina, animals were placed in a holding pen and assigned to treatment groups. All animals were then moved to Compartment 24 on the northeastern side of the SRS. Compartment 24 is shown as an inset on the SRS (Figure 1), which is shown as an inset of the southeastern United States with the range of the gopher

30 18 tortoise included. Compartment 24, a diamond-shaped compartment, is 971 ha in size and underlain largely by Lakeland and Blanton sands. The area is managed for red-cockaded woodpecker (Picoides borealis) on a 100-year+ timber rotation (USFS SRS, pers comm.). Longleaf pine and wiregrass restoration were undertaken and the site has areas of both mature longleaf and recently planted stands. Methods During late summer and fall of 2001, 101 tortoises were bucket-trapped or hand-dug from burrows on the donor site in McIntosh County, Georgia. Animals were then transported to the SRS. After weighing, blood collection, marking and removal of ticks, tortoises were placed in a holding pen on the SRS. Each tortoise was placed in a starter burrow (holes dug at similar declination to tortoise burrows, 1 m deep). Tortoises were placed in groups by sex/age class (adult male, adult female, juvenile) and then assigned randomly to 1 of 3 treatment groups. At the release area, 24 starter burrows were dug in each of three 1-ha release areas. Two of the release areas were pens enclosed with aluminum flashing which remained up for varying lengths of time. Animals in Release Group I (Table 1) overwintered off-site at a holding pen near Ellenton Bay on the SRS and were released individually at a starter burrow inside the unpenned release area during March to May, Release Groups II and III (Table 1) were both overwintered at the penned release areas and were released (i.e., had the aluminum flashing removed) on 8 July 2002 and 23 September 2002, respectively. After capture from the donor site, tortoises weighing more than 1100 g were fitted for radiotransmitters. Each transmitter weighed approximately 25.5 g and each tortoise was fitted for two. The transmitters were placed on the front of the carapace on either side of the head (to allow for mating) using epoxy. When feasible tortoises penned for longer periods were fitted

31 19 with dummy transmitters using the same epoxy when real transmitters were not available. Thirty-nine tortoises were selected for radiotagging, with thirteen tortoises in each treatment group. Following their release, tortoises were monitored daily using radiotelemetry. Each day a researcher walked to each individual animal and recorded its location using a Global Positioning System in NAD 27 projection. A flag noting the date, animal number and move number also were placed at this location. Care was taken not to disturb animals, particularly those moving, but animals did see the researchers nearly daily. Locations taken for each animal included information on habitat type, proximity to burrows, proximity to other tortoises and activity of the animal. Locations were corrected in Trimble GPS Pathfinder Office. Dispersed animals were picked up for return to the release area when they crossed the boundary-line of Compartment 24. However, in some instances, tortoises were allowed to continue traveling if there was no immediate problem finding the animal later or threat to the animal s survival. Movement Data Data were analyzed using SAS 8.0 and Microsoft Excel Statistical Analysis Package, as well as, Analyse-It for Excel. Single-factor ANOVA, correlation analysis and descriptive statistics information were generated for each release group and for age/sex classes within release (descriptive statistics only). In the single-factor ANOVA the independent variable was the length of penning time, whereas the dependent variable was the average distance moved in each treatment group. In correlation analysis, both daily temperature and rainfall were tested for correlation with daily distance moved (averaged across treatments). Daily movement distance (m/24-hour period) data for tortoises in each treatment group were averaged over two time periods the entire active period and the first 45 days post-

32 20 release prior to statistical analysis. Data for males, females, and juveniles within each release group were pooled for Analysis of Variance, acknowledging that differences may have occurred among these age/sex classes. However, all age/sex classes were equally represented among the 3 release groups. Therefore, the variation attributable to age/sex class was consistently distributed among the 3 release groups. Average movement data for each of these periods were log transformed prior to analysis because of heterogeneous variances. Transformed means and 95% confidence intervals were converted back to a linear scale for presentation in tabular form. Results During 30 March 2002 to 12 November 2002, 4,728 locations were recorded on 38 radiotagged tortoises including males, females and juveniles in three experimental treatments. This represents 37.6% of the total 101 tortoises relocated to the SRS in the fall of 2001 from McIntosh County, Georgia. Thirty-four tortoises were tracked from their release dates to the end of the active season. Four tortoises were lost during the study. These included: one female and one juvenile in Release Group I; one female in Release Group II; and one female in Release Group III. Dispersal out of the 971-ha timber compartment was common in Release Group I (Table 1), with 46% dispersing within the first 63 days following release (15.4% dispersed multiple times during the active season). During dispersal movement, burrows were generally not dug, but tortoises often created palettes at the end of each day. The palette generally consisted of a small depression created by the tortoise with a hood of pine straw or other debris that partially covered the tortoise. The average distance walked prior to dispersal by an animal in this group was 2,782.5 m (range 1, ,915.2). Animals in Release Group I that dispersed averaged 1.17 dispersals during the active season of 2002.

33 21 Several tortoises in Release Group I left the release area multiple times. Animals in all age classes and of both sexes demonstrated dispersal behavior in this release group. Only 23.1% of the animals in this release group remained in the timber compartment, established a burrow, stabilized movement, and attempted social interaction with other tortoises. However, 53.8% did exhibit all of these behaviors following at least one dispersal. In Release Group II, 23% of the radiotagged tortoises dispersed out of the 971-ha compartment during the first active season (Table 1). One animal in this release group dispersed twice. This animal later took over a burrow in the release area after being returned. The average distance traveled prior to dispersal in this release was 1,762.5 m (range 1, ,583.1). Animals that dispersed in Release Group II, averaged 0.23 dispersals during the active season of Two tortoises traveled into unsuitable habitat, but later returned to the uplands and established a burrow inside the compartment. No tortoises in Release Group III dispersed out of the 971-ha compartment during the first active season (Table 1). With the exception of one female that was lost, all tortoises in Release Group III that left the enclosure returned to a burrow in the release area. One female (#3031) went into a low area southeast of the enclosure and then returned to the release area and began occupying a burrow created by a male (#290) in Release Group I. Another female in this release group (#86) left the enclosure and dug a burrow in a stump hole, but later abandoned it and returned to the enclosure. The average distance moved per tortoise per 24-hour period following release was 13.7m (SE=2.21, N=565) within this release group. Average distance traveled per 24-hour period by tortoises in the first and second release groups during the same period were 8.02 m (SE= 1.75) and 6.08 m (SE=2.10), respectively.

34 22 Although the data were not analyzed for proximity of locations to roads and firebreaks tortoises were frequently located on both. Also, tracks were occasionally seen on roads indicating travel along these routes. Tortoises exhibited different movement-related behaviors associated with the type of movement they were making. Specifically, tortoises often created palettes (i.e., burrowing in straw/leaf litter partially covering the carapace) for shelter at the end of each day and during long-distance dispersal movement, sometimes covering themselves entirely. During forays, tortoises often were found in burrows later in the same day or the next morning. These burrows could belong to either the walking tortoise or a different one. Tortoises also were found foraging and often attempted to return to their own burrows either when encountered or later that same day. One tortoise also exhibited what might be described as searching behavior, using a particular burrow as a starting point and traveling in different directions on subsequent days. One particular male tortoise continued to move in different directions and return to the same burrow each day until he encountered a female in the release area. Beginning the day after finding her, he began visiting her regularly and stopped moving in other directions from his burrow. He continued to visit the release area, where the female was located throughout the active season. Interaction among tortoises and cohabitation of burrows was observed. On 115 occasions 2 or more tortoises were observed occupying the same burrow. Of these interactions 60 were between males and females (on 2 occasions 2 males were found with the same female). Thirtyfour of these interactions were between 2 males, 10 were between 2 juveniles, 6 were malejuvenile encounters, 4 were between a female and a juvenile and only 1 interaction was observed between a female and another female. Of the 10 records of cohabitation of 2 juveniles, all

35 23 occurred between the same 2 juveniles in Release Group III in the month of October, Presentation of results related to interaction among specific adult tortoises in each release is provided in Chapter 3. Movement out of the release (penning) area often resulted in either crossing of a dispersal boundary or movement followed by burrow construction. In the first release, all animals that left the release area (and were not lost) crossed the dispersal boundary without constructing a burrow. In Release Group II, 2 males, 2 females and 1 juvenile left the release area and established burrows within the compartment. One female in this release group crossed the dispersal boundary and established a burrow outside the compartment. In Release Group III, all animals that left the release area returned to the general area either within or surrounding the release pens. Results of the one-factor ANOVA are presented in Table 1 for both the 45-days following release and the entire active season. Movements of the tortoises were not correlated with rainfall or with temperature, as might be expected in a natural tortoise population. Discussion Our study has provided information on tortoise behavior post-release for a relocation effort. This data indicates that movement following relocation for cold-release tortoises (released without penning) is frequent even during cooler months of the active season. Tortoises in this study were frequently seen above-ground, particularly when dispersing. Ott (1999) conducted a large-scale movement study on a natural population of gopher tortoises at Ichauway Plantation in Baker County, Georgia from 1997 to She gathered information on movement between burrows, burrow usage, natural dispersal behavior and social interaction. Of 11,423 locations taken between April 1997 and June 1998, females were located above-ground on only

36 24 90 occasions and males were seen above-ground on only 88 occasions. Most of these occasions were between June and October Over 90% of males moved during the months of July, August and September 1997 and the majority of females moved at least one time in July. Movement distances were analyzed by moves between burrows for this study and locations were taken, at most, every other day. Ott (1999) also described a behavior seen in dispersing tortoises that we have called palette creation in this study. Daily movements of the tortoises were not correlated with rainfall or with temperature. Additionally, Release Group I moved frequently during the months of March, April, and May. Movement early in the active season is uncommon among gopher tortoises. According to the previously mentioned study by Ott (1999), movement typically peaked during the breeding season (July to August). In our study, peak movement for Release Group I occurred earlier in the season, indicating that a different factor may have facilitated movement. Even though, average 24-hour distance moved was not statistically different for Release Group I and Release Group II (Table 1), more tortoises in Release Group II established burrows within the compartment after moving from the release area. Also, although there was no statistical difference between Release Group II and Release Group III in average daily movement (Table 1), there was a higher level of interaction and lower rate of dispersal in Release Group III. This indicates that more tortoises remained in the compartment and interacted with other tortoises in their release group. The existence and importance of social structure among North American tortoises has long been recognized (Berry, 1986). However, incorporation of social structure in relocation projects has largely been disregarded. Our study implies that relocation stress may be mitigated by penning, which may allow time for both settling and interaction among tortoises moved

37 25 together. This may increase the likelihood of both successful relocation and future reproduction of a population. Conservation and Policy Implications Our study has indicated the importance of interaction following relocation for animals that demonstrate social structure. It is arguably crucial for this interaction to occur so that there will be opportunities for mating following release. Settling behavior (e.g., establishment of a burrow, continued maintenance of the burrow, and initial interaction with nearby tortoises) following relocation may be integral to establishing long-term social restructuring among relocated tortoises. Penning may provide both the time to settle and the opportunity to provide for interaction that might facilitate long-term social connections on a release site. The value of social structure and how it can be sustained or rebuilt following relocations should be afforded consideration prior to movement of animals. Additionally, the presence of existing populations and their effect on relocated tortoises may need further assessment. The success of a relocation program also depends upon reproduction and survival of offspring. Gopher tortoises experience heavy mortality in the first years of life, which results from several factors including small size and increased risk of predation due to softness of the shell. Witz et al. (1992) excavated 1,019 burrows yielding 400 tortoises. They estimated first year mortality for this population to be 92.3%. Wilson (1991) has provided juvenile survival estimates for juvenile gopher tortoises (ages 1-4) in west-central Florida. Survival estimates were based on radiotelemetry data from 32 tortoises over approximately 11 months, and varied throughout the year between 0.62 and 1.0. Age at sexual maturity varies throughout the range of this species (Wilson et al. 1997). Changes in age at sexual maturity may become evident in the SRS relocated population over the

38 26 next several years and should be monitored via x-ray of females each year as the activity season is likely shorter in the northernmost part of the range. Demographic data for North American tortoises is neither comprehensive nor equitable among species and populations. Witz et al. (1992) recommended including demographic analysis in relocation projects. The authors suggested determining success of relocation when the populations included either few or many reproductively mature animals. They postulated that populations with few intermediate-sized, mature animals and large numbers of juveniles may be more susceptible to extinction, which lead to their idea that it may be necessary to protect small individuals from predation until they reach reproductive age. Gopher tortoise relocation is controversial and has been considered by most conservation biologists to be largely unsuccessful. The reasons for this are perhaps clearer following this study. We now are beginning to understand the importance of settling behavior combined with the importance of social interaction among relocated individuals following the move. Most relocation projects have not included long-term monitoring of the population. Going beyond simple recapture studies, our study has defined a need to determine the level to which interaction between the animals occurs. The presence of the gopher tortoise on lands slated for development results in increasing conflict between development and conservation interests. Reading et al. (2002) presented a holistic model for reintroduction, which provides a starting point for shifting our thinking about how to improve success. Among the factors they identified were biology of the animal, issues of power and authority, organizations (program structure, bureaucracy, etc) and socioeconomic considerations. The shift towards a more comprehensive treatment of these efforts is a reflection of the understanding that contemporary extinction problems are the result of socioeconomic and political forces. As we found in our relocation study, these forces can

39 27 have a profound impact on not only the timeframe involved in these projects, but also the longterm success or failure of the effort. It is important for anyone undertaking such an effort to understand that failure to recognize the factors from the outset may doom the population and result in considerable expense without merit or success. The World Conservation Union /Species Survival Commission IUCN/SSC has developed Guidelines for Re-Introductions which may provide a starting point for anyone unfamiliar with the needs of such projects. It is our hope that our results may help address some of the general needs and concerns expressed by both Reading et al. (2002) and the IUCN. Grasslands and savannahs, which include the longleaf pine savannah occupied by the gopher tortoise (Noss and Cooperrider 1994), are among the most endangered terrestrial ecosystems in the United States. The longleaf-wiregrass ecosystem has undergone severe decline due to fire suppression and conversion to other land uses (e.g., agriculture and growth of other pine species in the southeastern United States). This system is home to a wide variety of rare and common species, including game species. Restoration efforts have become more numerous as the nature and management of this ecosystem has become better understood. Longleaf pine planting, wiregrass restoration, and restoration of fire management regimes have helped to re-establish these disappearing communities. Although some incentives exist for restoration of this habitat type (e.g., Conservation Reserve Program longleaf pine planting incentives), these incentives are not comprehensive. Although the gopher tortoise is currently federally protected in the western part of its range, it is not yet federally listed in Florida, Georgia or South Carolina, but development pressure and other concerns (e.g., disease and fire suppression) are thought to be causing further decline. We do not at present fully understand whether federal listing has saved the tortoise from

40 28 extinction in Mississippi and Alabama, which is a topic where further study is needed. It is also important, however, to address the need for conservation of habitat for this species on private lands and any disincentives that might exist for landowners. Daniel Hall of the Forest Biodiversity Program with the American Lands ALLIANCE (1999) suggested that incentives be targeted towards high priority actions not already or adequately required by law, such as habitat restoration for endangered or otherwise sensitive species, and protection and restoration of natural ecosystems and ecosystem processes that support species which have not yet been listed as threatened or endangered. Likewise, incentives should not be focused on activities already adequately fostered by markets. In many cases, proactive management of one species would undoubtedly benefit others. For instance, single species management for red-cockaded woodpecker may provide suitable habitat for many federally protected, rare and common endemic species (including many game species) in the longleaf-wiregrass system. If disincentives for endangered species management could be removed for private landowners and replaced with incentives to conduct management, a win-win situation for both the species and the landowner might develop (e.g., landowners are paid to provide long-term conservation), which in turn could benefit society as the public good provided by the conservation may far outweigh the individual land value alone (as suggested by Nelson and Fowler, 2002). Currently, the fear of reprisal for finding and managing for rare species or for habitat that might support them prevents landowners from doing so. As long as disincentives for proactive management of rare habitats and incentives for destruction of habitat exist alongside development pressure, current trends toward removal of suitable habitat for rare species will

41 29 continue. In the end, if we expect private landowners to conduct conservation, we must expect that at the very least they will not be hurt by doing it. Literature Cited Auffenburg, W., and R. Franz The status and distribution of the gopher tortoise (Gopherus polyphemus). Pages in R.B. Bury, editor. North American tortoises: conservation and ecology. U.S. Fish and Wildlife Research Report 12. and W.G. Weaver, Jr Gopherus berlandieri in southeastern Texas. Bulletin of the Florida State Museum, Biological Sciences 13: Berry, K.H Desert tortoise (Gopherus agassizii) relocation: implications of social behavior and movements. Herpetologica 42: Breininger, D.R., P.A. Schmalzer and C.R. Hinkle Gopher tortoise (Gopherus polyphemus) densities in coastal scrub and slash pine flatwoods in Florida. Journal of Herpetology. 28: Burke, R. L Florida gopher tortoise relocation: overview and case study. Biological Conservation 48: Clark, E. E. et al Gopherus polyphemus (Gopher Tortoise). USA: South Carolina. Herpetological Review 32: 191. Diemer, J.E The ecology and management of the gopher tortoise in the southeastern United States. Herpetologica 42: Tortoise relocation in Florida: solution or problem? Proceedings of the Desert Tortoise Council 1984: and P.E. Moler Gopher tortoise response to site preparation in

42 30 northern Florida. Proceedings of the Annual Conference of Southeastern Association of Fish and Wildlife Agencies 36: , D.R. Jackson, J.L. Landers, J.N. Layne, and D.A. Wood, editors Gopher tortoise relocation symposium proceedings. State of Florida Game and Fresh Water Fish Commission, Nongame Wildlife Program Technical Report 5. Doonan, T.J A demographic study of an isolated population of the gopher tortoise, Gopherus polyphemus; an assessment of a relocation procedure for tortoises. M.S. Thesis, University of Central Florida, Orlando, FL. Ernst, C.H., R.W. Barbour, and J.E. Lovich Turtles of the United States and Canada. Smithsonian Institution Press, Washington, D.C. Garner, J. and J. Landers Food and habitat of the gopher tortoise in southwestern Georgia. Proceedings of the Annual Conference of Southeastern Association of Fish and Wildlife Agencies 35: Gibbons, J.W. and M.H. Smith Evidence of orientation by turtles. Herpetologica 24: Gourley, E.V Orientation of the gopher tortoise Gopherus polyphemus. Animal Behavior 22: Hall, D Discussion paper: Incentives and land acquisition key tools for restoring fish and wildlife habitat. American Lands ALLIANCE. 2/12/99. Hallinan, T Observations made in Duval County, northern Florida, on the gopher tortoise (Gopherus polyphemus). Copeia 1923: Hansen, K.L The burrow of the gopher tortoise. Quarterly Journal of the Florida

43 31 Academy of Science 26: Jackson, D.R. and E.G. Milstrey The fauna of gopher tortoise burrows. Pages in J.E. Diemer, D.R. Jackson, J.L. Landers, J.N. Layne, and D.A. Wood, editors Gopher tortoise relocation symposium proceedings. State of Florida Game and Fresh Water Fish Commission, Nongame Wildlife Program Technical Report 5. 99pp + appendices. Knizley, E.J Gopher tortoise (Gopherus polyphemus) relocation project: monitoring the tortoise population and associate species of the tortoise burrow. M.S. Thesis. University of Florida, Gainesville, FL, USA. Landers, J.L., Techniques for restocking gopher tortoise populations. NEED PAGES in The gopher tortoise: Distribution, ecology, and effects of forest management. Final Report to Georgia Department of Natural Resources., W.A. McRae, and J.A. Garner Growth and maturity of the gopher tortoise in southwestern Georgia. Bulletin of the Florida State Museum, Biological Sciences 27: Lohoefener, R. and L. Lohmeier Experiments with gopher tortoise (Gopherus polyphemus) relocation in southern Mississippi. Herp Review. 17: Mann, T.M The status of Gopherus polyphemus in South Carolina. Pages in C.K. Dodd, Jr., R.E. Ashton, Jr., R. Franz, and E. Wester, editors. Proceedings of the 8 th Annual Meeting of the Gopher Tortoise Council, Florida Museum of Natural History, Gainesville, FL. McRae, W.A., J.L. Landers, and J.A. Garner Movement patterns and home range of the gopher tortoise. American Midlands Naturalist 106:

44 32 Means, D.B Responses to winter burrow flooding of the gopher tortoise (Gopherus polyphemus Daudin). Herpetologica 38: Morafka, D.J Neonates: Missing links in the life histories of North American tortoises. Pages in R. B. Bury and D.J. Germano, editors. Biology of North American tortoises. National Biological Survey, Fish and Wildlife Research 13. Nelson, N., and L. Fowler A primer on conservation easements and greenspace for the property tax division of the Georgia Department of Revenue. Office of Public Service and Outreach, College of Environmental Design, University of Georgia. Noss, R. F. and A.Y. Cooperrider Saving Nature s Legacy: Protecting and Restoring Biodiversity. Island Press. Washington, D.C.: 416p. Ott, J.A Patterns of movement, burrow use and reproduction in a population of gopher tortoises (Gopherus polyphemus): Implications for the conservation and management of a declining species. M.S. Thesis. Auburn University. 76 p. Reading,R.P., T. W. Clark and S.R. Kellert Towards an endangered species reintroduction paradigm. Endangered Species Update. 19(4): Wahlenburg, W.G Longleaf pine. Charles Lathrop Park Forestry Foundation, Washington, D.C. Wharton, C.H The Natural Environments of Georgia. Georgia Department of Natural Resources. Wilson, D.S Estimates of survival for juvenile gopher tortoises, Gopherus polyphemus. Journal of Herpetology. 25:

45 33, H.R. Mushinsky, and E.D. McCoy Home range, activity, and use of burrows by juvenile gopher tortoises in central Florida. Pages in R. B. Bury and D.J. Germano, editors. Biology of North American tortoises. National Biological Survey, Fish and Wildlife Research 13.,, and R.A. Fischer Species profile: Gopher tortoise (Gopherus polyphemus) on military installations in the southeastern United States. Technical Report SERDP-97-10, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Witz, B. W., D.S. Wilson, M.D. Palmer Estimating population size and hatchling mortality of Gopherus polyphemus. Florida Scientist. 55: Wright, S The distribution and population biology of the gopher tortoise (Gopherus polyphemus) in South Carolina. M.S. Thesis, Clemson University, Clemson, South Carolina.

46 34 McIntosh County, GA Figure 1.1: The range of the gopher tortoise with reference to the location of the SRS, Compartment 24 is shown as an inset on the upper right (Credit David Scott and Gopher Tortoise Council). March 2004.