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Study Site: Geographic Location. The majority of beaches along the Atlantic and Gulf coasts of the United States are located on barrier islands. These islands, separated from the mainland by a network of salt marshes and sounds, act as a “barrier” to the mainland, protecting it from damaging storm energy (Schoettle 1987). Jekyll Island is one of 14 barrier islands in the State of Georgia. Inclusive of both Atlantic-coast beaches and “inshore” beaches facing the St. Simons and St. Andrews Sounds, the island now has approximately 15.3 km of beach habitat (Fig. 1). This beach length, however, changes annually due to dynamic sand erosion and accretion. Unlike most developed barrier islands in the United States, those in Georgia are still largely undeveloped with much of their native habitats still intact (Schoettle 1987).

Figure 1. Jekyll Island in relationship to the remainder of Georgia’s barrier islands. The map of Jekyll Island is from the 1970s and highlights each section of beach by kilometer. Markers are placed at the south end of each section. The Km 13 marker at the southernmost point is positioned at the current 2013 location, as there has been ~500 m of sand accretion on the southern tip of the island since the 1950s.

Study Site: Human History. The natural and political history of Jekyll Island makes it a unique site for studying sea turtle ecology as well as the influence of coastal development. In 1888, Jekyll Island opened a private recreational club that served as an exclusive over-wintering destination, hosting many of the world’s wealthiest families. After the Jekyll Island Club closed in 1942, Georgia acquired Jekyll Island in 1947, and shortly thereafter in 1950, established the Jekyll Island State Park Authority (JIA) to oversee the conservation and development of the island (O.C.G.A. § 12-3-241). As mandated in 1971, 65% of Jekyll Island is to remain natural, while the other 35% of the island may be developed. However, during the 1950s and 1960s, there was a huge boom in island development and tourism, which included the construction of a causeway and bridge, beachfront hotels, and recreational facilities. The natural habitats of Jekyll Island, especially the coastal areas, were significantly modified during this time. Forty-foot dunes were flattened for approximately 2-3 km to provide a more direct view of the ocean, removing prime sea turtle nesting habitat. Additionally, approximately 5 km of rock-wall revetment was constructed on the beach to prevent shoreline erosion, eliminating over 30% of the suitable habitat for sea turtle nesting on the island. Further habitat degradation occurred through light pollution; lights from hotels and the old Peppermint Land amusement park illuminated the night sky, causing disorientation of both nesting adult sea turtles and emerging hatchlings (Bagwell 2001).

Jekyll Island is currently one of only four barrier islands in Georgia accessible via causeway, making it convenient for tourists. Uniquely, Jekyll is the only state park in Georgia that does not receive financial subsidies from the state. Instead, it sustains itself on tourism revenues and lease agreements from local residences and commercial entities. Specifically, this tourism focus for the island results in a concentrated overlap of human activity with shorebirds and sea turtle nesting, both spatially and temporally. Thus, this necessary interface at Jekyll Island necessitates a balancing act in sustainably managing the park’s natural resources while facilitating progressive, economically viable tourism.

Support and Management. Sea turtle population monitoring has always been an emphasis of the JISTP. However, while the goal of conducting population-level assessments of nesting females has been consistent, the intensity and commitment have varied over time. Although JIA has been the primary source of funding and resources for the JISTP since its inception, various other organizations have been involved with coordinating the logistical details of beach patrols. In the 1970s, additional funding for the JISTP came from the Coastal Georgia Audubon Society (CGAS) and private donations; these funds became heavily supplemented in the early 1980s by participation fees from education programs. Today, the Jekyll Island Authority Georgia Sea Turtle Center (JIA-GSTC; established in 2007), and the AmeriCorps program (established at the JIA-GSTC in 2009) provide the majority of the funding for the project. With the establishment of the JIA-GSTC Research Department in 2011, Jekyll Island now operates one of the most rigorous sea turtle patrol and research projects in Georgia.

Sea turtle monitoring on Jekyll Island officially began in 1972 with volunteer students participating in a summer biology course at Brunswick Junior College (currently, the College of Coastal Georgia). During these initial phases of the project, several paid technicians were also hired by Georgia Fish and Game (currently, Georgia Department of Natural Resources) and the United States Fish and Wildlife Service (USFWS). However, volunteers conducted the majority of patrols. Many of these volunteers were local college students, members of the Jekyll Island 4-H Center, Audubon Society members, and local residents. The project also attracted volunteers from out-of-state colleges such as Rutgers University, New York University, University of Rhode Island, and North Carolina State University. Patrols during 2007-2008 were conducted by unpaid interns from the JIA-GSTC and, starting in 2009, have been conducted by 6-10 AmeriCorps Members each season, supplemented by several unpaid interns and volunteers from the local area.

Survey Effort. Early reports from the JISTP suggest that nesting primarily shifted to the southern part of the island in response to human development. For this reason, in the 1970s, the JISTP decided that sea turtle patrols would focus on the southern-most portion of the island. From 1972 to 1977, nightly patrols were conducted each night until dawn, from the beginning of June (with occasional surveying in May) through the beginning of August. These patrols consisted of two teams, either on foot or by vehicle, and extended from the present-day Hampton Inn southward to St. Andrews Picnic Area (a distance of about 5 km). This portion of the beach was divided up into five sections, defined by differences in habitat type. By 1978, the inshore beach area west of Jekyll Point, at one time the most heavily-used nesting habitat on the island, had almost completely eroded away and became rarely used by nesting sea turtles. As a result, nesting reportedly expanded to the north, and patrol coverage followed. In 1980, the entire beach was patrolled for the first time in the history of the project. In the early 1990s, night patrols were reduced to six nights per week, coupled with one morning patrol each week. Additionally after nesting season ended in these years, patrols shifted completely to the mornings to monitor and inventory nests. In 1996, the present-day methodology of daily morning patrols was implemented; this is the monitoring regime that has been consistently maintained ever since. During the same year, the beach was also divided into 15 one-km sections for the purpose of refining the spatial accuracy in mapping sea turtle nesting activity.

From 2000-2006, no night patrols were conducted on Jekyll Island. Since the establishment of the JIA-GSTC in 2007, nightly tagging has resumed and is conducted from dusk to dawn for the full nesting season (beginning mid-May through July). Morning patrols are additionally conducted daily beginning 01 May until the last nest is excavated (usually the first week of October), beginning at 06:00 hrs, and cover the entire beach (kilometer markers 0 – 14).

Patrols are conducted primarily by vehicle along the majority of the beach (kilometer markers 0 – 12), but are conducted on foot along the southern part of the beach (kilometer markers 12 – 14) to reduce potential disturbance of nesting Wilson’s plovers (Charadrius wilsonia). The northern portion of Jekyll Island (kilometer markers 0 – 2) is highly erosional due to both natural dynamics and alteration of the beachfront from rock wall revetments (Jackson 2011); therefore, access to these areas is tide-dependent. Coverage of the northern portion of the island has varied from once-nightly to only being covered by dawn patrols. Female sea turtle identification on this portion of the island has continued in lieu of reduced tagging efforts, due to the recent efforts of Shamblin and colleagues (2011a).

Tagging Methods. Identifying individual sea turtles is critically important for understanding nesting behavior and ascertaining population trends, which provides data needed to support globally applied decisions regarding sea turtle conservation and management. While the primary goal of tagging turtles has remained virtually unchanged over the years, the methodology has changed considerably. Like many other projects, Jekyll Island initially tagged sea turtles with uniquely-coded yellow and blue plastic Rototags® in the 1970s (Fig. 2; Norton et al. in press and references therein). Each female that was encountered, regardless of whether or not she successfully nested, was tagged on her return to the ocean by first being flipped upside down and then fitted with a tag in the right front flipper. In 1978, the project started double-tagging each turtle in both front flippers with the “GA” tag series associated with the University of Georgia (UGA). However, as plastic tags quickly become scratched, unreadable, or lost (Balazs 1999), they were replaced on Jekyll Island with metal Monel® tags in the 1980s and metal Inconel® tags beginning in 1991. Currently, each time an untagged female is encountered, she is given a metal Inconel® 681 tag in each front flipper on the second large distal, posterior scale.

Figure 2. Loggerhead sea turtle tagging during 1970s; photo courtesy of former patrol participant Cam Simpson.

While retention of Inconel® tags has improved relative to that of Rototags®, these tags usually are not retained for the life of the animal (e.g., Norton et al. in press and references therein). As a result, Passive Integrated Transponder (PIT) tags have commonly been used to supplement double flipper-tagging as a more permanent form of identification and were incorporated on Jekyll Island in 1992. During the early 1990s, the PIT tags were applied subcutaneously in the right front flipper, then in the left front flipper in the late 1990s. Since various studies have shown that some PIT- tagging locations exhibit less tag migration than others (Wyneken et al. 2010), the PIT tag location was changed to the right shoulder in 2007 when sea turtle tagging resumed on Jekyll Island. Each PIT tag is currently scanned both prior to and after the application to ensure functionality and successful insertion with a Biomark® Pocket Reader EX PIT tag reader (which can detect both 125 kHz and 134.2 kHz tags).

Starting in 2005, genetic samples were collected on Jekyll Island as part of what has become a state-wide collaborative effort (beginning in 2008) by the Georgia Department of Natural Resources (DNR) and UGA (Shamblin et al. 2011a). From 2007 to the present, skin biopsies were collected from as many nesting females as possible. When a female was not encountered, or when a biopsy could not be collected from the encountered female, an eggshell from the nest was collected instead. By matching the maternal nuclear microsatellite DNA genotype from the skin biopsies with that of the eggshells, every nest can be assigned to a unique female turtle, even those nests for which the turtle was not encountered. This genetic identifier functions as a third type of identification tag (Shamblin et al. 2011b), allowing for a much more comprehensive understanding of loggerhead nesting behavior and ecology. Proper aseptic techniques are currently used to apply both flipper and PIT tags and for collecting skin biopsies, including the use of latex gloves, rinsing the skin with water, and then prepping the targeted area with betadine scrub and alcohol prior to each invasive procedure.

Morphometric and Habitat Data. The type of morphometric data collected from each turtle has varied over the years. In general, nesting female carapace length, both straight carapace length (SCL) and curved carapace length (CCL) measurements, have been collected using standard protocols. During several nesting seasons in the 1970s, plastron length and width data were also collected. Both straight and curved measurements were taken in combination for the first time in 1996. Since 2007, each turtle has been measured for CCL (notch-to-notch and notch-to-tip) using a soft measuring tape, SCL (notch-to-notch and notch-to-tip) using calipers, and carapace width using both a soft measuring tape and calipers.

In addition to physical turtle morphometrics, turtle crawl profiles and measurements have also been periodically recorded throughout the course of the project. Crawl widths were measured during many nesting seasons in an attempt to correlate crawl width with curved carapace width, but no correlation could be found from these data (Stephenson 1992). During the 1970s and 2010s, habitat measurements were recorded to better understand the spatial site fidelity, ecology and nest management of the nesting loggerhead sea turtle population of Jekyll Island. These included the distance from the crawl apex or nest to the high tide line and the current water line.

Nest Management. During the first three years of monitoring (1972-1974) conducted by Brunswick Junior College, the JISTP focused exclusively on collecting data from nesting female turtles at night. While eggs were counted and occasionally relocated on the beach to deter poachers, it was not until 1975 that Jekyll Island started managing some of its nests by use of a hatchery. Poaching on Jekyll increased to the point where it reportedly occurred almost every night (Ross 1972). Although 2009 was the last year of a documented poaching event for Jekyll Island, illegal poaching still occurs occasionally in Georgia, with the most recent case occurring on Sapelo Island on 27 May 2012 (Savannah Morning News 2013).

A hatchery was constructed in 1975 with the hopes of mitigating not only the pressures of poaching but also beach erosion, which is a process that is part of the natural dynamic on Jekyll Island. The hatcheries were small, self-releasing hatcheries located in undisclosed, isolated locations in the dunes. These locations often changed annually to avoid the discovery of their location by poachers. In 1979, the hatchery was “situated about 50-60 meters above spring tide line, on the open face of a sloping dune... consisting of four wooden frames with locking screen tops...” and had a screen attached to a depth of about 60 cm (McNamara et al. 1979). During the 1970s, typically fewer than a dozen of the nests that were confirmed on the beach (~25%) were relocated to hatcheries each season. Throughout the early 1980s, approximately 45 nests (~50-75%) each year were relocated into one of six hatcheries, while all nests in 1984 (n = 124) were relocated to hatcheries. Hatcheries were used on Jekyll Island from 1975-1986 and again in 1998, incubating an estimated 31,360 eggs. All years with available hatchery data, with the exception of 1976, reported a minimum average hatch success of 60% and a maximum of 85% (Jekyll Island unpubl. data).

In 2008, the Recovery Plan for the Northwest Atlantic Population of the Loggerhead Sea Turtle recommended the discontinuation of hatcheries as a management technique (NMFS & USFWS 2008). Relocating nests to a concentrated area may make them more susceptible to mass catastrophic natural events and predation. Additionally, using hatcheries has been shown to result in lower hatch success, skewed sex ratios and increased hatchling mortality (NMFS & USFWS 2008). Fortunately, due to the enforcement of anti-poaching laws, standardization of research efforts, and the tireless dedication of numerous individuals, nests on Jekyll Island are now managed in situ or relocated a short distance away from where they were originally laid if they are deposited in vulnerable areas (i.e., at risk of predation, erosion, inundation). Nest locations have been triangulated using wooden stakes starting in the early 1990s, and predator management using protective screening began in 1997.

In the early 1990s, relocating nests became a full-scale management practice on Jekyll Island. Despite the high levels of erosion present on Jekyll Island, the island has maintained one of the lowest relocation rates in the state of Georgia (<20%) until 2012, when the season experienced regular tidal surges into the dunes increasing the need to move more nests farther into the dunes. The project has observed an average hatch success rate of around 69% (n = 13 yrs), which is comparable with the 2010 Georgia state average among sites (69%; Dodd & Mackinnon 2010) and above the minimum designated by the Loggerhead Recovery Plan (60%; NMFS & USFWS 1991). Consistent data collection on Jekyll Island hatch success goes back to 1997, when daily monitoring of all nests throughout the duration of the entire incubation period became standard practice.

Public Education. A key component to any conservation program is having effective public education and increasing public awareness. In general, many conflicts result from lack of awareness; therefore, such conflicts often can be easily remedied by dissemination of information on what people can do to reduce their impacts on sea turtles. Providing the public with the opportunity to experience the awe of nature first-hand is the key to creating an environmentally-educated and engaged taxpayer base. In 1978, the JISTP and the CGAS initiated an educational “visitor patrol” program, which allowed groups of up to ten participants to assist with tagging and photograph nesting sea turtles. Visitor patrols were offered three nights per week from 21:30-23:30 hrs and attracted 200-300 participants annually. This program was a huge success and was continued into the 1990s by the Jekyll Island Recreational Department. Currently, the JIA-GSTC offers various experiential programs where participants can have the opportunity to observe nesting turtles and the activities of the research program. In addition to nighttime programming, the JIA-GSTC offers day trips to the beach where they can observe nest monitoring and excavation activities. Combined, these programs have hosted over 2,000 participants annually since 2007.

Database Collaboration. Jekyll Island has been the study site for a variety of sea turtle research projects over the past several decades. The University of Florida Archie Carr Center for Sea Turtle Research (ACCSTR) has distributed over 200,000 sea turtle tags to collaborators worldwide since 1955. The National Marine Fisheries Service (NMFS) Southeast Fisheries Science Center (SEFSC) established the Cooperative Marine Turtle Tagging Program (CMTTP) in 1980, having distributed over 100,000 tags. In April 1999, these two entities merged, and the CMTTP now operates under ACCSTR. The JISTP, however, did not begin its collaboration with ACCSTR and the CMTTP until 1991. Each year, since this collaboration was initiated, the project sends all tagging data from nesting females and the sea turtle rehabilitation patients to be managed in one centralized database. Because of this collaboration, the project has been able to reference substantial amounts of tagging data among islands. For example, it has verified the identity of a nesting female who was tagged as far back as 31 years ago – the record for the longest-known nesting period for loggerhead sea turtles. Such discoveries validate the critical need for highly-organized multi-agency collaborations for organizing and maintaining long-term datasets in order to monitor wide-ranging, long-lived species with low site fidelity. The long-term tagging data amassed on Jekyll Island represents an important component of a much larger tagging initiative throughout the southeastern U.S., and only through collaborative efforts will these data inform the long-term recovery and conservation of these threatened sea turtles.

Acknowledgements. We appreciate the efforts of the many people who have patrolled Jekyll Island over the 40 years of the program in the interest of sea turtle conservation. We acknowledge Dr. Terry Norton and the continued support of the Jekyll Island Authority for creating the Georgia Sea Turtle Center. We would like to acknowledge the AmeriCorps program which has supplied the beach personnel through service opportunities since 2009. We thank Peter Eliazar (ACCSTR-CMTTP), the Georgia DNR, in particular Mark Dodd, and the Georgia Sea Turtle Cooperative for maintaining an organized data network and for the peer support that is so necessary in the arena of wildlife conservation. We graciously thank Drs. Jim and Thelma Richardson and Rebecca Bell for launching loggerhead research in Georgia on Little Cumberland Island, which trickled across the creek and inspired an early and long-running research interest on Jekyll Island. We thank our beloved, late Thelma Richardson for never losing or discarding any data so that we have been able to retroactively build a nearly-complete long-term database of Jekyll Island sea turtle research. Lastly, we acknowledge our past and existing collaborators and give a salute to the relationships that have yet to come. As follows, our external collaborators with the JIA-GSTC Research Department and their associated projects deserve a noted presence on Jekyll beaches [topic (lead PI: year(s))]: [epibiota samples (Frick: 1998)], [genetics (Shamblin: 2005-2012)], [human impacts (Haman: 2007-2012)], [fire ants (Miller-Martin: 2008-2010)], [hatchling locomotion (Mazouchova: 2008)], [nutrition study (Norton: 2008-2012)], [bacteria study (Craven: 2010-2012)], [stable isotopes (Vander Zanden: 2011-2012)], [diatoms (Alverson: 2012)].

BAGWELL, T.E. 2001. Images of America - Jekyll Island, A State Park. Arcadia Publishing, Charleston. 71 pp.

BALAZS, G.H. 1999. Factors to consider in the tagging of sea turtles. In: Eckert, K.L., K.A. Bjorndal, F.A. Abreu-Grobois & M. Donnelly (Eds.). 1999. Research and Management Techniques for the Conservation of Sea Turtles. IUCN/SSC Marine Turtle Specialist Group Publication No. 4. pp. 101-109.

CALDWELL, D.K. 1962. Comments on the nesting behavior of loggerhead sea turtles based primarily on tagging returns. Quarterly Journal of the Florida Academy of Sciences 25: 287- 302.

DODD, M.G. & A.H. MACKINNON. 2010. Loggerhead turtle nesting in Georgia, 2010. Georgia Department of Natural Resources, Nongame Conservation Section, Brunswick. 21 pp.

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OFFICIAL CODE OF GEORGIA (OCGA). Title 12. Conservation and Natural Resources. Chapter 3. Parks, Historic Areas, Memorials and Recreation . Article 7. Public Authorities. Part 1. Jekyll Island-State Park Authority. § 12-3-241. 2010. Lease to Authority of Jekyll Island, Adjacent Marshes and Marsh Islands, Rights of Way, and Rights and Privileges of Every Kind.

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SAVANNAH MORNING NEWS. 2013. Sea turtle egg poacher pleads guilty. <http://savannahnow.com/news/2013-02-01/sea-turtle-egg-poacher-pleads-guilty>

SCHOETTLE, H.E.T. 1984. A Field Guide to Jekyll Island. Georgia Sea Grant College Program, The University of Georgia, Athens. 48 pp.

SHAMBLIN, B.M., M.G. DODD, D.A. BAGLEY, L.M. EHRHART, A.D. TUCKER, C. JOHNSON, R.R. CARTHY, R.A. SCARPINO, E. MCMICHAEL, D.S. ADDISON, K.L. WILLIAMS, M.G. FRICK, S. OUELLETTE, A.B. MEYLAN, M.H. GODFREY, S.R. MURPHY & C.J. NAIRN. 2011a. Genetic structure of the southeastern United States loggerhead turtle nesting aggregation: evidence of additional structure within the peninsular Florida recovery unit. Marine Biology 158: 571-587.

SHAMBLIN, B.M., M.G. DODD, K.L. WILLIAMS, M.G. FRICK, R. BELL & C.J. NAIRN. 2011b. Loggerhead turtle eggshells as a source of maternal nuclear genomic DNA for population genetics studies. Molecular Ecology Resources 11: 110-115.

STEPHENSON, K.B. 1992. Summary report, Jekyll Island Sea Turtle Project, 1992 seasonal data. Unpublished Report. 10 pp.

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