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  1. Preliminary Results of a Gopher Tortoise Relocation Project at Gator Hole Preserve, Lee County, FloridaConny Spurfeld (B.A. Biology student), Candy Long (B.A. Environmental Studies student) and Nora Egan Demers (Associate Professor of Biology and Interdisciplinary Studies)Florida Gulf Coast UniversityFt. Myers, Florida • Ashton and Ashton Associates Management recommendations details: • Gator Hole Preserve • 175 acres acquired and managed by Lee County Conservation 20/20 program • Parcel isolated by development • Tortoise release area 1 (TRA1) • southwest parcel fenced to enclose approx 30 acres • relocation site for road expansion project • Last burned in 2003 (plan to burn this winter) • Ten soil mounds placed in Aug. 2005 to facilitate burrowing • No tortoise on site before relocation • 35 gophers relocated April (29) – June (6) of 2006 • 16 were unmarked juvenile and sub-adults (58-144 mm and 1 injured (220 mm adult) • 19 adults marked; 5 male; 15 females 170-350 mm • May 2006 9 burrows identified • June, 2006 40 burrows identified • Oct, 2006 55 burrows identified • July 2007 59 burrows identified (data from this study) Figure 4: Rebar poles were used to permanently mark burrow location were placed during the summer of 2007 Abstract: Studies were conducted within a fenced relocation site of approximately 30 acres at Gator Hole Preserve in southwest Florida. A population of 35 gopher tortoises in total was relocated to the site in early Spring of 2006. For the study, gopher tortoise burrows were located, marked, and GPS coordinates and measurements of the dimensions of each burrow entrance were recorded. The burrows were monitored for activity and labeled as active or inactive for several summer months. For the purpose of the study, it was assumed that one tortoise occupied each burrow, and only measurements taken for active burrows were used for population results. No dead tortoises have been found. Because the size of burrow openings correlate to the size of the tortoises inhabiting them, it is possible to surmise the relative age groups of the tortoises present on the relocation site. Age classification as surmised by carapace length of tortoise measured during relocation was compared with burrow sizes. From these data, a population structure of the tortoises at the site will be estimated. A comparison of our population structure data with that of a healthy gopher tortoise population will provide an analysis of the relocation success at this particular site. Further studies will need to be conducted in order to analyze factors contributing to success, such as foraging habitat, harvesting, and gopher tortoise health. • Discussion: • The vast majority of burrows were located along the berm (an artifact of former agriculture activity) perimeter of the fenced area. • C. Spurfeld is currently comparing distance between burrows as measured on the ground with calculation of the same from Trimble GPS data. • Population structure is being studied by C. Long . Below are data that show comparison of carapace length to burrow width using Alford’s (1980) conversion factor. • The population indicated by these active burrow measurements reflects the juvenile skew of the recently relocated population. • 15 pair of burrows with virtually the same burrow widths; • 3 sets were not active. • Future studies will compare the location of these sets to see if they support the notion that the same tortoise may have multiple burrows to access different forage areas. • We were told of humanitarian relocations of at least one additional tortoise to this property during the summer of 2007. • Harvesting of saw palmetto berries was observed on site. • Although not noted on this site, several other gopher tortoise preserves in southwest Florida have experienced harvest – once with tortoises found in bags containing saw palmetto berries, and another where the burrow had been dug up. • Efforts are underway to mount a Spanish-language educational campaign regarding the threatened status of Gopher tortoises. • Conclusions: Studying Gopher tortoise populations and habitat is a powerful tool to introduce undergraduate students to scientific research and the role of local government in conservation practices. • Stronger ties to research groups with more expertise and experience would improve our ability to provide meaningful research and experiences. Figure 5: C.S. used a Trimble unit to record precise locations of each burrow. Figure 2: 2005 Aerial of Gator Hole Preserve- Figure 6: Location of the 59 burrows identified and marked during the summer of 2007 (C. Spurfeld) Figure 1 Location of Lee County lands with gopher tortoises Figure 3: Location of soil piles within fenced TRA 1 References cited: Alford, R. A. (1980) Population structure of Gopherus polyphemus in northern Florida J. Herp. 14(2):177-182 Ashton and Ashton Associates (2006 Monitoring Report ) Gator Hole Preserve TRA1 Forage Monitoring and Revised Management Recommendations. Acknowledgements: This project would not have been possible without support from Lee County Parks and Recreation staff. Lee County DOT provided funds to stake and mark burrows. Lee County Parks also provided the maps of lands in Lee County and soil pile locations.

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