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The leopard tortoise (Geochelone pardalis) is the largest of the southern African tortoise species and has a wide distribution range. However, there is a lack of ecological and physiological information about the species, especially arid and semi-arid regions. The Nama-Karoo, an arid region of South Africa, is subject to large fluctuations in rainfall, food availability and ambient temperatures (Ta). This study focused on the thermal behaviour, thermoregulatory, digestive and metabolic plasticity of the leopard tortoise within the Nama- Karoo biome. Seasonal changes in activity patterns and body temperature (Tb) were investigated in free ranging leopard tortoises in the Nama-Karoo. Leopard tortoises had unimodal daily activity patterns in winter, bimodal in summer, and there were daily and seasonal differences in the extent to which certain behaviours were practiced. Daily activity behaviours were executed at lower Tb and at lower Ta in winter compared to summer. In summer, core Tb of all tortoises oscillated on a daily basis well below maximum Ta, while core Tb of all tortoises in winter oscillated well above the daily Ta range. Tortoises were therefore able to maintain their Tb independently of Ta. Differences in Tb as measured from various positions on the tortoises body was investigated in relation to Ta. There was a strong seasonal and temporal influence on the relationship between various Tb’s, with the skin and external shell temperatures being more variable in response to fluctuating Ta’s compared with cloacal and core Tb. Cloacal temperatures were significantly different to other Tb measurements suggesting that it should be treated with circumspection as an exclusive measure of Tb. Heating and cooling rates of leopard tortoises were investigated in the field and under controlled laboratory conditions to determine if the tortoises maximise operational daily activity periods, and to determine the effect of behaviour and size on the rate of heat flux. In the laboratory, cooling rates were faster than heating rates in summer and winter for all size classes and decreased with increasing body mass. Leopard tortoises had significantly faster heating and cooling rates in winter than in summer. Free-ranging leopard tortoises had faster heating rates than cooling rates and their heat flux was largely independent of Ta. Heating and cooling rates were dependant on body mass and surface area-to-volume ratio of individuals. Under experimental conditions, tortoises physiologically adjusted their rate of heat flux, while free-ranging tortoises used physiological and behavioural mechanisms to minimise the risk of overheating, to aid thermal inertia and maximise operative activity time. Seasonal climatic cycles and fluctuating daily temperatures influence the oxygen consumption (VO2) of reptiles, however the result of these effects on metabolism in chelonians is poorly understood. The effect of seasonal and daily differences in Ta on VO2 was investigated. Leopard tortoises’ VO2 was slightly higher than reported for other chelonians. There were significant differences in tortoise VO2 at different Ta’s during the day and night and in different seasons. This metabolic plasticity is possibly an adaptive mechanism to cope with unpredictable environmental conditions. Unpredictable climatic conditions lead to unpredictable food and water availability. Little is known how tortoises adjust dietary parameters in response to food type and water availability, and if this affects body mass, energy and water balance. Therefore this study also considered whether leopard tortoises adjusted food transit rate, food intake and water loss to cope with a diet fluctuating in fibre and water content, and whether body mass, energy and water balance were maintained. Leopard tortoises fed a high fibre, low water content diet had lower food intake rates, longer food transit times, but lower daily energy assimilation compared with tortoises fed a low fibre, high water content diet. Tortoises fed a high fibre, low water content diet had lower urine osmolality, but similar total water loss to those fed a high fibre, low water content diet. The results indicate that tortoises can adjust digestive parameters according to diet composition and exercise some control over energy and water balance. It is concluded that leopard tortoises show a high degree of plasticity in their thermal behaviour and physiology which allows survival in an unpredictable environment, particularly where there are fluctuations in rainfall, food availability and Ta’s. Seasonal and daily variation in thermoregulation, metabolic rate and the uptake of energy allows the leopard tortoise to maximise the duration of operative temperature, to minimise energy loss and to use variable and unpredictable seasonal resources. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.

Gopher tortoises (Gopherus polyphemus) are keystone species mainly due to their burrow construction. Gopher tortoises can also impact the plants around them, but it is rarely quantifiable due to constraints in dispersal studies including time period and seasonality of fruit. The objective of this study was to measure the effect gut-passage has on a native Florida stone-pitted shrub, the cocoplum bush (Chrysobalanus icaco), as well as to attempt to model the relationship between the gopher tortoise and the plant using our unique field site. This study shows that gut-passage has a significant effect on the germination rate of the cocoplum, allowing it to germinate faster than control groups. This study also found that a model involving covariates relating to tortoise movement as a predictor for cocoplum intensity was favored over a homogeneous null model. We believe the pattern of plants is nonrandom and relates to the gopher tortoise’s seed dispersal. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Trabalhamos com 8 jabutis, 4 fêmeas e 4 machos da espécie Geochelone carbonaria, para descrição da morfologia macroscópica e microscópica de luz e eletrônica de varredura do rim. Observamos que os rins são órgãos compactos, de forma piramidal, coloração vermelha escuro, e de aspecto cerebróide. Histologicamente o néfron apresenta glomérulo de Malpighi, túbulo contornado proximal, túbulo contornado distal, alça de Henle, túbulo coletor e ureter. Observamos também que todas estas estruturas secretam grânulos de muco neutro. / Eight tortoises have been used in this study i.e., 4 females and 4 males belonging to the Geochelone carbonaria species, in order to describe the macroscopic morphology, light microscopic morphology and the scanning electron microscopic morphology of the kidney. It has been observed that the kidney are compact, pyramid-shaped organs with a dark reddish coloring and circunvolutioned appearance. From a histological point of view, the nephron presents Malpighian corpuscle, proximal contoured tubule, loop of Henle, collector tubule and ureter. It has been also noticed that every renal structure secrete neutral-mucus granules.

Effective conservation requires efficient population monitoring, which can be challenging for rare species like the desert tortoise (Gopherus agassizii). We compared two alternative survey methods that can be used to monitor tortoise populations: distance sampling and site occupancy estimation. In 2005 and 2006 combined, we surveyed 120 1-km transects to estimate density and 40 3-ha plots with five presence-“absence” surveys to estimate occupancy of Sonoran desert tortoises in two mountain ranges in southern Arizona. We found that monitoring programs based on an occupancy framework were more efficient and had greater power to detect linear trends. We also found that habitat use by Sonoran desert tortoises was influenced most by slope and aspect, contrasting with patterns observed in the Mojave Desert. Given its efficiency, power, and ability to gauge changes in distribution while accounting for variation in detectability, occupancy offers a promising alternative for long-term monitoring of Sonoran desert tortoise populations.

Turtle and Tortoise Protection Legislation Abstract The thesis focuses on turtle and tortoise protection in international law, Czech legislation on breeding turtles in captivity, and legislation concerning protection of biodiversity against turtles as alien or invasive species. The objective is to describe and analyse turtle protection legislation and if concluded that the legislation is not sufficient, make proposals de lege ferenda. Another objective is to describe biodiversity protection legislation in a situation when a turtle species is in a position of alien or invasive species. The first part contains introduction to the matter considered. It includes biological classification, the importance of turtles for ecosystems, with special focus on sea turtles, and threats to turtles, again with special focus on sea turtles. The second part focuses on turtle protection in general agreements on nature protection - global and regional. In the first chapter, there are global agreements which are then divided to The Convention on Biological Diversity, agreements on protections of habitat, and agreements on species protection. In the second chapter, there are regional "land" agreements listed. The third part concentrates on specifics of sea turtle legislation. At first, relevant parts of UNCLOS are mentioned....

Trabalhamos com 8 jabutis, 4 fêmeas e 4 machos da espécie Geochelone carbonaria, para descrição da morfologia macroscópica e microscópica de luz e eletrônica de varredura do rim. Observamos que os rins são órgãos compactos, de forma piramidal, coloração vermelha escuro, e de aspecto cerebróide. Histologicamente o néfron apresenta glomérulo de Malpighi, túbulo contornado proximal, túbulo contornado distal, alça de Henle, túbulo coletor e ureter. Observamos também que todas estas estruturas secretam grânulos de muco neutro. / Eight tortoises have been used in this study i.e., 4 females and 4 males belonging to the Geochelone carbonaria species, in order to describe the macroscopic morphology, light microscopic morphology and the scanning electron microscopic morphology of the kidney. It has been observed that the kidney are compact, pyramid-shaped organs with a dark reddish coloring and circunvolutioned appearance. From a histological point of view, the nephron presents Malpighian corpuscle, proximal contoured tubule, loop of Henle, collector tubule and ureter. It has been also noticed that every renal structure secrete neutral-mucus granules.

A diverse assemblage of exquisitely-preserved fossil animals and plants were collected from Sawmill Sink blue hole in Abaco, Bahamas. More than 40 species have been identified including extinct tortoise, an extant crocodile, and birds that no longer live in The Bahamas. This study addresses the mechanisms that preserve fossils in blue holes and discusses paleoecological implications from faunal diversity and sediment composition. Blue holes are waterilled caves with surface openings that may trap animals and surface-driven vegetation. In Sawmill Sink the talus cone within the halocline acts as a substrate on which organics collect that drive microbe ecology. Their byproducts, hydrogen sulfide and anoxia, inhibit biological destruction and delay necrolysis. Low tidal flow and quiescent water conditions further enhance stability of the depositional environment. In addition, subaerial conditions during glacial lowstands allowed owls to roost; their deposits formed a rich assemblage of small fossil vertebrates.

Gopher tortoises are ecosystem engineers whose burrows provide habitat to >350 species. Prescribed fire is used to manage tortoise habitat, but fire timing is mostly restricted to the vegetative dormant season. Restricted fire timing in combination with white-tailed deer competition may negatively affect tortoises. To address these concerns, we quantified these species’ dietary overlap and conducted a field experiment to examine impacts of fire phenology on plants and animals. Although tortoises and deer consumed ~75% of the same plants, their diets were statistically dissimilar. Fire altered plant community composition and increased foliar crude protein and phosphorus while decreasing calcium. Deer detections were unaffected, but tortoises were detected more in fire treatment plots. We simultaneously monitored burrow and surface temperatures and found burrows provide thermal refuge. Our data suggests that fire timing affects plants in ways that can affect gopher tortoises, and burrows may mitigate some negative impacts of climate change.

As people live in an area, they leave behind an assortment of cultural items they once utilized. Some of these items may include pottery or bones from animals they used as food. Analysis of these bones can give a glimpse into how they managed their resources in the environment around them, including which ecosystems they chose to exploit, and which taxa they prioritized for consumption or cultural purposes. The Indian River Lagoon in Florida is a diverse costal lagoon with many various overlapping ecosystems and ecotones available for prehistoric peoples to utilize. Comparing the frequency of taxa representing different local environments such as the marine, terrestrial, and estuary environments will help us to understand how the people who lived at the Penny site prioritized these many resources. This study intends to analyze turtle remains specifically because different species are present in all three environments. Amongst the four analyzed test units at the Penny site, 1,417 turtle elements were identified. Overall, turtle shell (carapace or plastron) was the most identified element across each analyzed test unit. Results demonstrate that turtles were not only consumed, but their shell was used for cultural purposes as well.