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The gopher tortoise tick, Amblyomma tuberculatum, has a unique relationship with the gopher tortoise, Gopherus polyphemus, found in sandy habitats across the southeastern United States. We aimed to understand the overall bacterial community associated with A. tuberculatum while also focusing on spotted fever group Rickettsia. These tortoises in the Southern Mississippi region are a federally threatened species; therefore, we have carefully trapped the tortoises and removed the species-specific ticks attached to them. Genomic DNA was extracted from individual ticks and used to explore overall bacterial load using pyrosequencing of bacterial 16S rRNA on 454-sequencing platform. The spotted fever group of Rickettsia was explored by amplifying rickettsial outer membrane protein A (rompA) gene by nested PCR. Sequencing results revealed 330 bacterial operational taxonomic units (OTUs) after all the necessary curation of sequences. Four whole A. tuberculatum ticks showed Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes as the most dominant phyla with a total of 74 different bacterial genera detected. Together Rickettsiae and Francisella showed >85% abundance, thus dominating the bacterial community structure. Partial sequences obtained from ompA amplicons revealed the presence of an uncharacterized Rickettsia similar to the Rickettsial endosymbiont of A. tuberculatum. This is the first preliminary profile of a complete bacterial community from gopher tortoise ticks and warrants further investigation regarding the functional role of Rickettsial and Francisella-like endosymbionts in tick physiology., (Copyright © 2016 Elsevier GmbH. All rights reserved.)

Department of Defense lands are essential for providing important habitat for threatened, endangered, and at-risk species (TER-S). However, there is little information on the effects of military-related contaminants on TER-S on these lands in field situations. Thus, this study examined genotoxicity and oxidative stress in gopher tortoises ( Gopherus polyphemus) on Camp Shelby, MS-the largest known population of this species, which is listed as an 'endangered species' in Mississippi and a 'threatened species' by the U.S. government. Blood was collected from tortoises at 19 different sites on the base with different levels of habitat quality (high-quality and low-quality habitat) and military activity (high, low, and no military activity). Oxidative stress was quantified as lipid peroxidation and GSSG/GSH ratios, while DNA damage was determined using flow cytometry. Our results suggest that: (1) for tortoises residing in low-quality habitats, oxidative stress and DNA damage increased with increasing military activity, while in high-quality habitats, oxidative stress and DNA damage decreased with increasing military activity; (2) in the absence of military activity, tortoises in high-quality habitat had higher levels of oxidative stress and DNA damage than those in low-quality habitat, and (3) there were interactions between military activity, habitat quality, and landuse in terms of the amount of observable DNA damage and oxidative stress. In particular, on high-quality habitat, tortoises from areas with high levels of military activity had lower levels of oxidative stress and DNA damage biomarkers than on reference sites. This may represent a compensatory or hormetic response. Conversely, on low-quality habitats, the level of oxidative stress and DNA damage was lower on the reference sites. Thus, tortoises on higher-quality habitats may have a greater capacity for compensatory responses. In terms of management implications, it is suggested that low quality habitats should be a higher priority for remediation, and lower priority for conducting military activities. [ABSTRACT FROM AUTHOR]

Gopher tortoises ( Gopherus polyphemus) are candidates for range-wide listing as threatened under the U.S. Endangered Species Act. Reliable population estimates are important to inform policy and management for recovery of the species. Line transect distance sampling has been adopted as the preferred method to estimate population size. However, when tortoise density is low, it can be challenging to obtain enough tortoise observations to reliably estimate the probability of detection, a vital component of the method. We suggest a modification to the method based on counting usable tortoise burrows (more abundant than tortoises) and separately accounting for the proportion of burrows occupied by tortoises. The increased sample size of burrows can outweigh the additional uncertainty induced by the need to account for the proportion of burrows occupied. We demonstrate the method using surveys conducted within a 13,118-ha portion of the Gopher Tortoise Habitat Management Unit at Fort Gordon Army Installation, Georgia. We used a systematic random design to obtain more precise estimates, using a newly developed systematic variance estimator. Individual transects had a spatially efficient design (pseudocircuits), which greatly improved sampling efficiency on this large site. Estimated burrow density was 0.091 ± 0.011 burrows/ha (CV = 12.6%, 95% CI = 0.071-0.116), with 25% of burrows occupied by a tortoise (CV = 14.4%), yielding a tortoise density of 0.023 ± 0.004 tortoise/ha (CV = 19.0%, 95% CI = 0.016-0.033) and a population estimate of 297 tortoises (95% CI = 210-433). These techniques are applicable to other studies and species. Surveying burrows or nests, rather than animals, can produce more reliable estimates when it leads to a significantly larger sample of detections and when the occupancy status can reliably be ascertained. Systematic line transect survey designs give better precision and are practical to implement and analyze. [ABSTRACT FROM AUTHOR]

ABSTRACT Gopher tortoise ( Gopherus polyphemus) populations are declining range-wide primarily because of habitat loss, fragmentation, and degradation, but low recruitment due to nest predation also may be contributing to this decline. The relationship of nest location and nest survival is unknown. Therefore, our objective was to determine whether nest location influenced depredation risk and potential recruitment success. Between 30 May 2013 and 3 September 2014, we constructed and monitored 105 artificial gopher tortoise nests (45 in 2013 and 60 in 2014) with 35 nests at each of 3 classifications of nest sites: within active burrow aprons (i.e., the mound of sand at the burrow entrance), inactive burrow aprons, and open sandy sites. Using the artificial nests, we investigated the influence of nest site classification, distance to road, and prescribed fire frequency (<1 year and 1 year since burn) on gopher tortoise nest survival. Additionally, we monitored 21 natural nests at burrow aprons to assess predation patterns as compared to artificial nests. Seventy-two (57%) of 126 nests were fully depredated during the study, and predation rates at artificial and natural nests were similar. We identified predators at 48 nests using trail cameras; the nine-banded armadillo ( Dasypus novemcinctus) was the primary nest predator (69%). Nests in open sandy areas away from burrows exhibited greater daily survival rates (DSR; 0.991 ± 0.005 SE) compared to nests in burrow aprons (active burrow aprons: 0.967 ± 0.018; inactive burrow aprons: 0.949 ± 0.027). Additionally, nests at locations burned the year of the study had a lower chance of survival (DSR: 0.959 ± 0.022) than nests at locations burned the previous year (DSR: 0.991 ± 0.005). Management practices that maintain open sandy areas (e.g., prescribed fire) away from burrows may increase tortoise nest survival. Fire return intervals of >1 year that are implemented frequently enough to maintain open sandy areas would be beneficial to nesting tortoises. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Change in vegetation structure alters habitat suitability for the threatened gopher tortoise ( Gopherus polyphemus). An understanding of this dynamic is crucial to inform habitat and tortoise management strategies. However, it is not known how the choice of the sample grain (i.e., cell size) at which vegetation structure is measured impacts estimates of tortoise-habitat relationships. We used lidar remote sensing to estimate canopy cover around 1573 gopher tortoise burrows at incrementally larger sample grains (1-707 m2) in 450 ha of longleaf pine ( Pinus palustris) savanna. Using an information theoretic approach, we demonstrate that the choice of grain size profoundly influences modeled relationships between canopy cover and burrow abandonment. At the most supported grain size (314 m2), the probability of burrow abandonment increased by 1.7% with each percent increase in canopy cover. Ultimately, detecting the appropriate sample grain can lead to more effective development of functional relationships and improve predictive models to manage gopher tortoise habitats. [ABSTRACT FROM AUTHOR]

Private landowners play a pivotal role in determining whether or not rare species persist in regions where privately owned land is extensive. The range of the gopher tortoise ( Gopherus polyphemus) is confined to the Southeastern U.S., a region predominantly under private ownership, and thus the status of this species is largely dependent upon land management decisions made by private landowners. We sent an anonymous mail survey to 2,584 individuals to examine factors affecting gopher tortoise occurrence on private lands in Mississippi (adjusted response rate of 23%). Few respondents (19%) reported currently having tortoises on their property, although many had them in the past (30%). Tortoises were persisting primarily on larger properties with longleaf pine that were not managed chiefly for timber production. In general, respondents were largely unaware of habitat requirements of tortoises or effects of various land management practices on them, and few reported using management techniques that benefit tortoises, such as prescribed burning. Most respondents (57%) knew of wildlife incentive programs, but were hesitant to enroll because they did not want to commit to managing their property in a particular manner (34%). We suggest actions that could improve the likelihood of tortoise persistence in this region, as well as changes that could be made to incentive programs to increase landowner participation. These suggestions should be relevant to the conservation of other rare species on private lands in other regions. [ABSTRACT FROM AUTHOR]

Given the increasing expansion of human dominated landscapes it often becomes necessary to relocate endangered and at-risk species from existing habitat areas. Further, there is growing research stating that climatic and atmospheric changes attributed to climate change are already affecting species distributions and geographic ranges, requiring endangered species to be relocated. Existing reserve design models mostly focus on choosing the optimal land area given existing species distributions and have not incorporated species relocation as a criterion. This paper introduces linear integer programming formulations for the relocation of multiple populations of a species at risk to clustered conservation areas. We present a basic clustered relocation model and extend the model to minimize the distances of relocation. We apply the models to a dataset related to Gopher Tortoise (GT), a keystone species currently considered ‘at risk’, at Ft. Benning Georgia where expanding military training needs require the relocation of GTs. We present the results and discuss the trade-off between compactness and relocation considerations using an efficiency frontier. [Copyright &y& Elsevier]

Focuses on the efforts of the Florida Fish and Wildlife Conservation Commission to identify the vulnerability of red-cockaded woodpecker and gopher tortoise for the purpose of conservation and management. Factors that influence conservation and management alerts based on population trends; Reclassification of red-cockaded woodpecker and gopher tortoise; Importance of analyzing the ecological role of species in evaluating conservation alerts.

The western population of the gopher tortoise (Copherus polyphemus) was listed as threatened under the Endangered Species Act in 1987 due to extensive population declines. Declines have been linked to site conversion of native pine (Pinus spp.) forests for urban development, agriculture, and commercial forest management. We conducted surveys to detect tortoise burrows on corporate timberlands in southern Mississippi and southwestern Alabama during summer 1994. We surveyed 2,759 0.5-ha strip transects on soil types of 9 different suitability categories for gopher tortoises. We found 460 active and 264 abandoned burrows on the 1,380 ha surveyed. Edaphic and vegetative conditions, such as sandy soils and total and midstory canopy coverage, influenced gopher tortoise occurrence. Logistic regression analyses revealed that active burrow occurrence was related positively to deep, sandy soils and related negatively to total canopy closure and fine loam soils with limited sand content. Abandoned burrow occurrence was related positively to increasing midstory canopy closure and selected soil types. Sandy soils and open overstory canopy that created favorable burrowing, nesting, and foraging conditions were important influences in active burrow occurrence. Vegetation management techniques, such as prescribed fire, midstory control, and intermediate forest stand thinning, are recommended on gopher tortoise conservation areas and connective corridor habitats on commercial timberlands. We theorize that restoration of longleaf pine (P. palustris) forests on sandy ridges can produce desirable core habitats and dispersal corridors for gopher tortoises in landscapes dominated by intensively managed pine plantations. [ABSTRACT FROM AUTHOR]