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Age and growth-related parameters provide a better understanding of life-history adaptations and trade-offs and can be studied in the wild through capture-mark-recapture (CMR) or sclerochronology (i.e., skeletochronology and counting growth marks on hard structures). In chelonians, skeletochronology is limited to carcasses, CMR is limited by time and funding constraints, but counting shell growth annuli (SGA count) is a cheaper and faster alternative. A long-term CMR study in Testudo graeca from south-eastern Romania allowed us to compare the age estimated by the two sclerochronology methods using carcasses, and calibrate the results with data obtained from recaptured tortoises. We found that the accuracy of SGA counts significantly decreased with time (i.e., years between captures and older individuals). Skeletochronology showed the best results with long bones (i.e., ulna, radius, femur), but overall underestimated the age when compared to SGA counts; we obtained comparable results from these two methods in tortoises up to 17 years old. The oldest age estimated by skeletochronology alone was 28 years, 30 years by SGA counts, and 40 years by SGA counts when calibrated by CMR. The growth models using age estimations from both skeletochronology and SGA counts were similar, highlighting their usefulness in monitoring growth trajectories. Our study showed that while age estimation in tortoises is challenging, a combination of methods can improve its accuracy. [ABSTRACT FROM AUTHOR]

Ectotherms exhibit varying geographic size patterns shaped by environmental and evolutionary factors. This variability is noticeable within taxonomic groups. For instance, certain testudinids follow Bergmann's rule (body size increases with latitude) and Rensch's rule (sexual size dimorphism correlates with body size), while others do not. Here we hypothesize that body size patterns can even vary within a monophyletic lineage. To address this, we evaluated the body size patterns of the spur-thighed tortoise Testudo graeca that globally follows Bergmann's and Rensch's rules. We specifically investigated the influence of climate variables, latitude and elevation within the subspecies T. g. whitei throughout its natural distribution in North Africa, and in a recently expanded range in SE Spain (20 kya old). We found that males were smaller than females in both regions. The tortoises from SE Spain were smaller than those from North Africa, which showcased the smallest sizes ever reported for the species. Latitude was the main variable to explain tortoise body size. In particular, body size decreased with latitude in both regions, which contrasts with Bergmann's rule expectations based on species-level findings. Finally, to further contradict species-level expectations, we did not find any statistical correlation between sexual size dimorphism and body size across the two studied regions. Such contradictory outcomes reveal complex geographic size patterns within T. graeca and raise conservation questions about demographic viability at smaller-sized sites. [ABSTRACT FROM AUTHOR]

A previous study on the feeding habits of Moorish tortoises in west-central Morocco suggests that these animals are selective herbivores, but the nutritional consequences have not been examined. Because of the potassium excretion load, which requires water and/or nitrogen loss, we predicted that tortoises do not have salt glands. Moorish tortoises prefer plants rich in water and protein but low in potassium (PEP index). To this end, we studied the spring diet of adult tortoises in an arid steppe in west-central Morocco during two seasons of relatively dry years (2011-2012) using feces analyses. We also estimated the relative abundance of potential food plants by stratified sampling under the canopy of jujube bushes Ziziphus lotus. We statistically compared diet to plant abundance. Finally, we assessed plant species' nutritional composition (water, crude protein, and potassium) available to tortoises. Results showed that species assemblages differed significantly between the two plant communities in both years. Nevertheless, tortoises consumed only about 5-6 and nearly the same species at the study site in 2011 and 2012, respectively. The plants consumed by the tortoises had the highest positive PEP index values indicating that there was more water and nitrogen in the food than is needed to excrete potassium. [ABSTRACT FROM AUTHOR]

Defining priorities is important both in research and in conservation, especially when knowledge gaps are hindering successful management. In this review, we quantify the knowledge gaps for all non-marine West African chelonians based on 21 criteria. Additionally, we combine these knowledge gaps with each species' maximum size, range size, presence in nationally protected areas, and IUCN Red List or TFTSG provisional status to introduce a ranking of species conservation priority in the region. Our analyses revealed a divergence between which species are lacking research studies and which would benefit most from conservation actions, though Cyclanorbis elegans is the species that is both the least-known and most-in-need of conservation. Broadly, Pelomedusidae are in the greatest need of research, yet they are also collectively the least threatened. Conversely, Trionychidae and Testudinidae have received greater research attention in most cases, however, these two families represent the greatest conservation priorities amongst West African chelonians. Our analyses also enabled us to evaluate which criteria representing aspects of chelonian biology have been most overlooked by the scientific community. Priorities for future research include reproductive and long-term population studies, each of which are critical for informing conservation actions and evaluating the results of those actions. [ABSTRACT FROM AUTHOR]

Turtles as many other reptiles are capable of orientating their bodies toward the sun. This conduct requires the presence of an internal biological chronometer in the organism that regulates this behavior. Thus, a description of the internal clock in these reptiles is of interest. The assessment of locomotor activity can be considered a reliable indicator of biological clock function. This study aimed to investigate the effect of different artificial photoperiod and ambient temperature schedules on total locomotor activity of female Chelonoidis chilensis and its rhythmicity. Six C. chilensis specimens were exposed to different artificial photoperiods and temperature regimes each fixed for seven days. It was observed that the activity period during the different experimental schedules was close to the 24 hours indicating a daily rhythmicity. Moreover, all tortoises showed a similar total locomotor activity pattern displaying the most of motion during light phase. Under the condition of constant light tortoises exhibited a self-sustaining rhythm not entrained to light and temperature zeitgebers, thus, suggesting its possible endogenous periodicity. Though this study deepens the knowledge on the rhythmic system of C. chilensis , further investigations are needed to achieve a more detailed understanding of tortoise biological clock. [ABSTRACT FROM AUTHOR]

We studied the diet and vegetation composition of Egyptian tortoise, Testudo kleinmanni , habitat in North Sinai, Egypt. Dietary data was recorded through direct observations and the vegetation composition was recorded through the use of quadrats and line transects in 66 sampling points (33 in tortoise areas and 33 in non-tortoise areas). Our results showed that vegetation of Egyptian tortoise habitat had high species richness, Simpson's diversity index, and vegetation cover in contrast to areas without Egyptian tortoises. These tortoises ate thirty four species of plants, a majority of these being perennials, with most feeding observations occurring in spring and winter. The consumption of perennials may enable Egyptian tortoises to find and consume food in an arid environment with low, variable and unpredictable rainfall. The plants most consumed were rare in our vegetation survey, suggesting food preferences. Our study suggests that Egyptian tortoises, which rely on vegetation for food and refugia, may suffer if vegetation cover and richness decrease. [ABSTRACT FROM AUTHOR]

Macro- and microhabitat preference of Testudo hermanni boettgeri , the eastern subspecies of Hermann's tortoise, was investigated utilizing modified methodology for the western subspecies which emphasized the importance of habitat heterogeneity preservation. The study objective was to explore the habitat preferences of the eastern subspecies of T. hermanni. Research was conducted within the same year at four localities in Eastern and Southeastern Serbia. Macrohabitat determination was conducted using a 0 to 5 land cover score system (coverage with herbaceous, bushy or tree vegetation) for 4 m2 tortoise encounter surroundings. Microhabitat analysis was carried out by determining the plant species in closest contact with the tortoise in the moment of recording. Plants were classified into six groups: 1) aromatic, 2) bramble, 3) herbaceous, 4) thorny shrub, 5) tree and 6) non-thorny shrubs. X 2 test was used for comparison between expected and empirical habitat preference. Results confirmed that the most attractive macrohabitats for Eastern Hermann's tortoises in this part of the Balkans are meadows and open shrublands, with the addition of dense forest (important in wormer months), what is concordant with earlier data from the Mediterranean part of former Yugoslavia. The most attractive microhabitats were "herbaceous plants", followed by "bramble". [ABSTRACT FROM AUTHOR]

Geochelone elegans is one of the most heavily traded tortoise species of the world, and confiscated tortoises are frequently released into the wild, without knowledge about their origin. Using for the first time samples from Pakistan and Sri Lanka, we examined phylogeographic differentiation of G. elegans using 2289 bp of mitochondrial DNA. We found weak intraspecific differentiation without a clear geographic pattern. We suggest that natural phylogeographic differentiation may have been already destroyed by massive releases of confiscated non-native tortoises. The presence of two distinct clades on Sri Lanka, however, could also be the result of a natural range expansion of a mainland lineage into the distribution range of a lineage endemic to Sri Lanka during Pleistocene low sea level stands. We propose that a systematic screening of the genetic differentiation of wild G. elegans should be conducted across its entire distribution range to provide a sound basis for the relocation of confiscated tortoises. [ABSTRACT FROM AUTHOR]

Collection for the pet trade has been considered one of the major threats to the Mediterranean spur-thighed tortoise Testudo graeca , since it modulates the size and structure of the species' populations and, therefore, their demography. Maamora forest is one of the most suitable habitats for this species. The proximity of the forest to Rabat indicated the possibility of these tortoise populations being particularly sensitive to over-collecting. Population demography was studied in four populations, in protected and unprotected areas in Maamora forest. The results showed significant differences as regards population size and structure between protected and unprotected areas. They specifically highlighted: i) higher density (23-17 indiv · ha−1) balanced populations in the protected areas, in which young adults were predominant, ii) a higher body condition in the protected areas, especially the females, and iii) a low density (5.5 ind · ha−1) more unbalance population in the unprotected areas, in which older females and younger males were predominant. In addition, a survey carried out by interviewing local adults (n = 200) showed that most people owned tortoises (61%, n = 200), mainly juveniles (65%, n = 123). The respondents stated that their tortoises had been captured in the forest (68%, n = 123). Maamora forest is home to one of the highest density populations of Mediterranean spur-thighed tortoises documented to date, and its conservation is essential if this species is to be maintained. Our social survey suggested that one of the challenges is to change the social perception of the Mediterranean spur-thighed tortoise as a pet and highlight its intrinsic ecological value. [ABSTRACT FROM AUTHOR]

Until the late 1970s spur-thighed tortoises Testudo graeca, endemic to the Mediterranean region, were exported from range countries in large volumes for the pet trade. Testudo graeca was included on CITES Appendix II in 1975, and in 1978 Morocco introduced national protection, banning domestic and international trade. However, the species is still openly traded in Moroccan markets. In 2013-2014 we conducted 48 surveys in 20 Moroccan towns and cities and single surveys in two Spanish exclaves to assess trade levels, size-composition, turnover, and variation between cities. We recorded 3267 T. graeca in 107 shops in 12 cities. Of 989 tortoises measured, two-thirds measured <10 cm (~2-8 years of age) and <3% could comprise first-year individuals. There is a clear relationship between price and size, with 'average' tortoises costing USD 9.20. The largest volumes were observed in Tangier (869) and Rabat (752), two cities that are well-connected centres of export. The largest proportion of shops selling tortoises was in Agadir (78%) and Fez (63%), and turnover was highest in Tangier (32/week) and Casablanca (28/week). Country-wide turnover was ~30% after two weeks and ~80% after 10 weeks. Annual turnover was estimated at 3500-7000 tortoises, with a monetary value of USD 30 000-60 000. Predictors for volumes of trade and proportion of shops selling tortoises are: the number of wildlife shops in markets, diversity of wild vertebrate species the shops have on offer, and city population. While legal, large-scale international trade of spur-thighed tortoises from Morocco has diminished over the last decades, domestic smaller-scale trade continues to impede their conservation. Consistent punitive measures are required to enforce new laws. [ABSTRACT FROM AUTHOR]

The spider tortoise (Pyxis arachnoides) is endemic to the coastal, dry forests of southwest Madagascar, one of the country's most threatened habitats. Very little is known of the biology of this Critically Endangered species. We devised a three year capture-mark-recapture study to assess mean annual survival for the following cohorts; juvenile, adult male, adult female and adult of both sexes, for a population of spider tortoises using a Cormack-Jolly-Seber model. Low recapture probabilities prevented the modelling of all but the adult of both sexes cohort. Mean annual survival was 0.823 (SE± = 0.15; 95% CI = 0.565-1.0). We hypothesise that habitat loss could be impacting the survival of this cohort; however establishing control data to test for this is difficult because of the widespread habitat loss, even within protected areas. Therefore we suggest extending the study across a number of gradients of impacted habitat and increase the duration of the study to assess this risk to the population and improve model robustness. [ABSTRACT FROM AUTHOR]

Gopherus flavomarginatus (Testudinidae) is endemic to a series of discontinuous, isolated basins collectively known as the Bolson de Mapimí in the Chihuahuan Desert. Its numbers declined after catastrophic levels of exploitation during the mid-20th century. However currently, the Bolson Tortoise appears to be on a path to recovery owing to intensive, sustained conservation efforts. We sequenced an 842-bp-long fragment of the D-loop from 76 individuals distributed throughout the species' range. The results revealed only two haplotypes. An AMOVA showed that 95% of the variance occurred among populations, whereas the remaining 5% was explained by genetic differences within populations. Tectonic processes together with ecological transformation during the Pleistocene and Holocene may be responsible for the reduction in this species' genetic variation. A bottleneck during which a significant percentage of the haplotype diversity was lost would result in genetic homogeneity. Although there is demographic growth, the lack of genetic diversity is indicative of the potential crisis that the Bolson Tortoise is facing, and awareness must be brought to this situation. [ABSTRACT FROM AUTHOR]

We studied the thermal ecology of Testudo hermanni hermanni in Menorca during late spring. We measured body temperatures of adult individuals, together with air and substrate temperatures at points of capture. Sunlight exposure (full sun, filtered sun, or shade) and type of substrate were also recorded. Body temperatures were similar between sexes (mean = 29.95°C) as were air temperatures between gender capture sites (mean = 28.33°C). Conversely, females were found in areas with a higher substrate temperature (31.60°C) than males were (29.15°C). Moreover, the correlation between body and air temperatures was stronger than it was between body and substrate temperatures, as found in other populations of this species. The tortoises were usually found in full sun, and the proportion of animals found in each sunlight category was similar between sexes. Our results contribute to the knowledge of the thermal ecology of the western Hermann's tortoise. [ABSTRACT FROM AUTHOR]

The Hermann's tortoise is a strictly European species found mostly in areas with Mediterranean and sub-Mediterranean climes and, especially the subspecies T. hermanni hermanni, has to deal with various threats which reduced its geographic distribution to only a few isolated populations. Thus, with the objective of recovering natural populations of the species, numerous reintroduction projects are being carried out throughout its historical and prehistorical geographic distribution. The aim of our study is to evaluate the success of the T. hermanni reintroduction project carried out in the Albufera de Valencia Natural Park since 2011, through the analysis of movements, home range sizes and habitat use in a new environment. The recorded activity pattern presents two peaks, one in spring and another in August, and the hibernation period (from December to February) is the same as observed in other populations. We did not find significant differences in home range sizes between sexes, but a tight relation between home range sizes and body sizes with larger individuals having larger home ranges. This relation was not observed for core areas (Kernel at 50%). Considering the habitat use, we did not find differences between the groups of individuals we defined, but different types of habitats were used differently. "Scrub" was the most frequented (~50%), followed by "dunes" (~20%), "mallaes" (~20%) and "forest" (<20%). Our results can be used to improve the success of future reintroduction projects by directing ideal habitat, timing and carapace size of released Hermann's tortoises. [ABSTRACT FROM AUTHOR]

Tortoises that live in regions where food plants grow in winter may have to cope with relatively low environmental temperatures to obtain resources. The speckled tortoise, Homopus signatus, inhabits an arid winter rainfall range where it is active in winter and spring at environmental temperatures well below its preferred body temperature. Although H. signatus is a threatened species, we have no information how it deals with low environmental temperatures. Therefore, we made continuous recordings of behaviour in nine female H. signatus on 29 days in the early spring. The group of females as a whole showed activity (i.e., behaviours other than hiding) throughout the day in a unimodal pattern. However, individual tortoises were active only for approximately 4.5 h per day and spent as much as 73% of their active time basking, mostly under the protective cover of shrubs. In addition, a negative relationship between the percentage of active time spent in sun and environmental temperature indicated that H. signatus used active behaviours other than basking to absorb heat, particularly on cold days. Tortoises completed all active behaviours other than basking in 1.2 h per day, including a mere 24 min of feeding, probably facilitated by the abundant availability of food plants in the early spring. We predict that a reduced availability of food plants for H. signatus might lead to increased active time and possibly increased predation pressure, or to a decreased proportion of active time spent basking and reduced body temperatures. [ABSTRACT FROM AUTHOR]

We studied morphological traits of Psammobates oculifer over its range to evaluate patterns in sexual size dimorphism (SSD) and geographic variation. Females were larger than males for 40 of the 44 characters measured and the growth trajectories of female parameters, scaled to body size (ANCOVA and MANCOVA on carapace length), most often followed juvenile patterns. For males, either the slopes or elevations of morphometric parameters were lower than in females. These divergent growth trajectories resulted in shape differences with female shells being higher and wider than the shells of males. Males matured at a smaller age and size, and had wider hind feet and larger shell openings relative to females; the latter being due to a shorter and narrower plastron, a shorter bridge length, and a bigger anal gap and cranial space. These male characteristics possibly enhance mobility for mate searching and combat, as well as courtship and mating behaviour. Small sample sizes for females in two of the three regions restricted geographic evaluations to males, for which shell shape, front foot width and hind leg length of the eastern group differed from the others. We interpreted these variations as the consequence of differences in the substratum and vegetation openness over the range of the species. [ABSTRACT FROM AUTHOR]

To avoid the possible extinction of the last native population of western Hermann's tortoise in the Iberian Peninsula it is essential to make sound management decisions. Knowledge of macro and microhabitat use and home range size has considerable practical value for land managers. With this aim we first studied the home range and habitat preferences in western Hermann's tortoises by radio tracking 15 adults weekly from March 2008 to May 2009 in three localities within the Albera population range (NE Iberian Peninsula). We estimated home ranges with Fixed Kernel estimator (FK) and Minimum Convex Polygon (MCP) after checking tortoise site fidelity. We observed that home range size did not differ significantly between males and females (mean FK = 2.01 ha, mean MCP = 3.01 ha). Secondly, we studied macrohabitat selection using a vegetation map. Preferred habitats were open shrubland, open forest and barren land during the activity period, and dense forest, dense shrubland and open shrubland during the hibernation. Next, we assessed microhabitat selection along five periods of the annual cycle: hibernation, emergence from hibernation, spring, summer and autumn. We then located marked tortoises weekly and classified the plant species observed in each location. Principal component analyses showed that tortoises selected shrubs with trees during hibernation, bramble during summer and herbaceous habitat during the breeding season. All these results can provide guidelines for management programs that set aside areas of habitat critical to conserve viable populations, although it is also important to prevent mortality from forestry works. We therefore tested a new brush cutter head accessory to achieve tortoise-safe undergrowth clearing. To this aim we distributed 52 frozen hybrid tortoises among eight plots of 100 m2, cleared six of these plots with the accessory and two without it, and evaluated the scars of the blade on caparaces. We observed no damage in plots that were cleared with the accessory but scars in most carapaces in the plots cleared without it (with potential mortality ranging from 40% in neonates to 100% in adults). These results outline the importance of supporting habitat management decisions with proper field studies. [ABSTRACT FROM AUTHOR]

The availability of suitable refuges to buffer temperature extremes may be a critical determinant in the distribution of arid-zone ectotherms. We studied refuge selection of Kalahari tent tortoises over five seasons in two vegetation types to assess how seasonal climate change, vegetation type, and the size difference between sexes influence refuge selection. Plant refuges accounted for 78% and mammal burrows for 22% of refuges used. Burrow use did not differ between vegetation types or sexes but its use increased exponentially with maximum temperature, indicating that mammal burrows may be an essential resource to protect small-bodied tortoises against summer heat. Kalahari tent tortoises preferred grass refuges to other growth forms, whether shrubs or grasses were dominant in the habitat. Tall grass was selected in excess of availability, by males and females in both vegetation types, probably because it was denser than short grass and provided better protection against heat and predators. The increased use of short grass refuges in colder months may be linked to thermal needs because this growth form allowed P. oculifer to bask in filtered sunlight whilst being in cover. Females made greater use than males did of short grass refuges, perhaps because their larger size necessitated longer exposure to sunlight. Body size differences also explain why males required wider and denser refuges than females did to protect them against environmental hazards. Our results underscore the complexities of refuge selection by an arid-zone ectotherm and the role it may play in their distribution. [ABSTRACT FROM AUTHOR]

Pyxis arachnoides is a Critically Endangered Malagasy tortoise for which little data about its natural history and genetic variation are available. This lack of knowledge complicates undertaking conservation measures considering Pyxis genetic diversity. Here, we describe six new microsatellites for Pyxis arachnoides from wild specimens and several localities, and the cross amplification of two Astrochelys radiata microsatellites. Of these microsatellites, two are monomorphic among the three distinct subspecies and a closely related species, while the remaining six are polymorphic. Microsatellite data are needed for this species to study the inter- and intra-subspecies genetic diversity, especially for the highly endangered subspecies P. a. hrygooi, which currently occurs only in remote localities. The availability of polymorphic microsatellites will allow identifying the population of origin of individuals and will aid in justifying their management as separate evolutionary lineages for conservation purposes. The rationale is to preserve both evolutionary processes and adaptive potential. [ABSTRACT FROM AUTHOR]

Most species of tortoises are seriously threatened worldwide. Chelonians are long-lived organisms characterized by slow demographic traits; mathematical modeling estimated that a high rate of juvenile annual survival (i.e. >0.6 on average) is essential for the persistence of populations. Unfortunately, current knowledge about free-ranging juveniles is fragmentary. Under field conditions, young tortoises are very secretive, they remain sheltered beneath bushes, and they escape capture. The resulting lack of information impairs the assessment of key parameters such as juvenile survival, habitat use, or recruitment rate and thus seriously impedes both accurate population viability analyses and conservation planning. Large-scale monitoring of different populations of a threatened species (Testudo hermanni hermanni) confirmed that juveniles are rarely seen in the field. In 2011, we placed corrugated fibrocement slabs as alternative refuges for small tortoises in a densely vegetated study site. Many juveniles sheltered under the space offered by the corrugations; consequently they were easily captured and recaptured. Our results suggest that this simple technique may significantly improve the detectability of juveniles, providing access to the life history traits of this otherwise elusive age cohort. The slabs also provide protection against predators (such as dogs and birds) which further suggests that these refuges may also improve the survival of the smallest and most vulnerable individuals. [ABSTRACT FROM AUTHOR]

The spider tortoise (Pyxis arachnoides) is endemic to the coastal, dry forests of southwest Madagascar, one of the country's most threatened habitats. Very little is known of the biology of this Critically Endangered species. We devised a three year capture-mark-recapture study to assess mean annual survival for the following cohorts; juvenile, adult male, adult female and adult of both sexes, for a population of spider tortoises using a Cormack-Jolly-Seber model. Low recapture probabilities prevented the modelling of all but the adult of both sexes cohort. Mean annual survival was 0.823 (; ). We hypothesise that habitat loss could be impacting the survival of this cohort; however establishing control data to test for this is difficult because of the widespread habitat loss, even within protected areas. Therefore we suggest extending the study across a number of gradients of impacted habitat and increase the duration of the study to assess this risk to the population and improve model robustness. [ABSTRACT FROM AUTHOR]

Gopherus flavomarginatus (Testudinidae) is endemic to a series of discontinuous, isolated basins collectively known as the Bolson de Mapimí in the Chihuahuan Desert. Its numbers declined after catastrophic levels of exploitation during the mid-20th century. However currently, the Bolson Tortoise appears to be on a path to recovery owing to intensive, sustained conservation efforts. We sequenced an 842-bp-long fragment of the D-loop from 76 individuals distributed throughout the species' range. The results revealed only two haplotypes. An AMOVA showed that 95% of the variance occurred among populations, whereas the remaining 5% was explained by genetic differences within populations. Tectonic processes together with ecological transformation during the Pleistocene and Holocene may be responsible for the reduction in this species' genetic variation. A bottleneck during which a significant percentage of the haplotype diversity was lost would result in genetic homogeneity. Although there is demographic growth, the lack of genetic diversity is indicative of the potential crisis that the Bolson Tortoise is facing, and awareness must be brought to this situation. [ABSTRACT FROM AUTHOR]

In the last decade, Asian populations of Testudo graeca were split into as many as 10 species based on morphology and morphometry and then subsequently synonymized based on genetic evidence. We generate new morphometric data for six of these disputed species from Turkey, a major center of morphological and genetic diversity for Asian T. graeca. We test the concordance of our data with previous morphological assignments. Our morphometric data and analyses do not support all of the results of previous morphometric studies. Instead we find that putatively named taxa from the Mediterranean coast (“antakyensis”, “anamurensis”, and “terrestris”) are not morphometrically distinct. On the other hand, some inland populations from eastern Turkey (“armeniaca” and “perses”) are morphometrically distinct as previously claimed. Tortoise populations from northern and southern Turkey, which may correspond to the ibera and terrestris mt clades, also appear to be morphometrically distinct. In this respect, the morphometric data reflects the emerging genetic pattern, although the picture is complicated by a lack of genetic sampling within Turkey and morphometric studies outside of Turkey. [ABSTRACT FROM AUTHOR]

Using a nearly range-wide sampling, we investigated phylogeographic differentiation and mitochondrial diversity of Testudo horsfieldii, the only tortoise species confined to Central Asia. We identified three major haplotype clades with mainly parapatric distribution that do not correspond well to the currently recognized three subspecies. One clade is restricted to the Fergana Valley and seems to represent a previously overlooked evolutionarily significant unit. Another clade, consisting of several largely parapatrically distributed haplotypes, occurs in the north and the central southern part of the species' range. The third clade, likewise comprising several largely parapatrically distributed haplotypes, was identified from the south-eastern corner of the Caspian Sea in the west, from Afghanistan and Pakistan in the east and from two more northerly sites in western and south-eastern Uzbekistan. It is possible that this clade also occurs in eastern Turkmenistan and adjacent Afghanistan, regions not sampled for the present study. The generally parapatric distribution of individual haplotypes, even within each of the three major clades, suggests advanced lineage sorting, either due to limited dispersal abilities, glacial isolation in distinct local microrefuges or both acting in accord. The localized distribution of endemic haplotypes in the northern and central plains as well as in the mountainous eastern and southern parts of the distribution range supports the existence of multiple microrefuges there. Records of haplotypes of distinct clades in sympatry or close geographic proximity are likely the result of Holocene range expansions. In recent years, thousands of confiscated steppe tortoises were released into the wild. The detected mitochondrial differentiation offers a powerful tool for nature conservation, as a means of determining the geographic origin of confiscated tortoises and selecting suitable reintroduction regions. [ABSTRACT FROM AUTHOR]

We investigated the mitochondrial phylogeography of spur-thighed tortoises (Testudo graeca) in the Western Mediterranean. In North Africa, four major lineages (A-D) occur that together constitute a well-supported clade corresponding to one of the six major clades within T. graeca; the North African clade is sister to a Caucasian clade representing the subspecies T. g. armeniaca. Phylogenetic relationships between the North African lineages are badly resolved. Lineage A is distributed in Tunisia and adjacent Algeria, lineage B in Algeria and northern Morocco, lineage C in the Libyan Cyrenaica Peninsula, and lineage D north of the High Atlas Mts. and in the Souss Valley (southern Morocco). Lineage B is subdivided into two subgroups, B1 (eastern Morocco and Algeria) and B2 (north-western Morocco). Italian tortoises harbour haplotypes of lineage A, Spanish tortoises of subgroup B1. Based on a relaxed molecular clock calibrated with fossil evidence, the six major mtDNA clades of T. graeca are estimated to have diverged approximately 4.2-1.8 Ma ago; the split between the clades representing the eastern subspecies T. g. ibera and T. g. terrestris is younger than the split between Western Mediterranean tortoises and T. g. armeniaca. The Western Mediterranean lineages A-D were dated to have diverged at least 1.4-1.1 Ma ago; B1 and B2 split approximately 0.7 Ma ago. Our results suggest that Italian and Spanish tortoises were either introduced or originated from trans-oceanic dispersal in historic or prehistoric times. Spur-thighed tortoises invaded North Africa probably across Near Eastern landbridges that emerged in the Late Tertiary. Their diversification in North Africa seems to be correlated with habitat aridization cycles during the Pleistocene. The ranges of the Western Mediterranean lineages largely correspond to the distribution of morphologically defined subspecies in North Africa, with exception of T. g. graeca and T. g. whitei, and of T. g. lamberti and T. g. marokkensis, which are not differentiated. We propose to lump the first two subspecies under the name of T. g. graeca and the latter under the name of T. g. marokkensis. The complex differentiation of spur-thighed tortoises in North Africa implies that the model of a bipartite east-west differentiation, as proposed for other Maghrebian amphibians and reptiles, may be too simplistic, reflecting incomplete locality sampling rather than actual phylogeographic differentiation. [ABSTRACT FROM AUTHOR]

The Amazonian tortoise Geochelone denticulata may play an important role in forest dynamics due to its highly frugivorous diet, ability to disperse viable seeds, and predilection for resting in forest gaps for thermoregulation. The purpose of our study was to evaluate the species' effectiveness as a seed disperser. We measured dispersal quantity (abundance of seeds in feces, frequency of droppings, and population density of the disperser) and dispersal quality (movement patterns, habitat use, germination rates of dispersed seeds, and recruitment probabilities of seedlings) in a SW Amazonian forest, in Peru. Population density was calculated by mark-recapture and line-transect methods. Eight individuals were radio-tracked to monitor habitat use. Diet was described from fecal samples, which were washed to count seeds and for germination experiments. Seedling survival in different environmental conditions was monitored for three plant species. Population densities with mark-recapture estimates (0.15-0.31 individuals/ha) were much higher than with line transects estimates (0.0025 individuals/ha). Diet included fruit of 55 different plant species. Dispersed seeds had high germination rates (average 76%). In spite of their low activity, we documented long seed dispersal distances (average 89.6 m). Tortoises showed a marked preference for the open-canopy swampy forest, where long term recruitment was not favorable for seedlings of the species examined. However, the high solar radiation in this forest type promoted survival of pioneer seedlings in the short term. In conclusion, while G. denticulata did not perform a very efficient role in terms of the quantity of seed dispersal, the species can be considered efficient in many aspects of dispersal quality. [ABSTRACT FROM AUTHOR]

We compared variation in phalangeal and carpal morphology of the Central Asian Testudo horsfieldii, a burrow-digging tortoise species, with its sister taxon T. hermanni, a Mediterranean species without extensive digging behaviour. Thirty-two Testudo horsfieldii kazachstanica shared the same phalangeal formula (0-2-2-1-1). The distal carpal 1 and metacarpal I as well as the pisiform were consistently lacking, sometimes also the medial centrale. Phalangeal morphology was more variable in Testudo hermanni hermanni. In 29 specimens four phalangeal formulae were found that differed with respect to the reduction of digit 1 (1-2-2-2-1, M-2-2-2-1, D-2-2-2-1, 0-2-2-2-1). The pisiform develops late in ontogeny and is lacking in very most juveniles and subadults. In contrast to T. h. kazachstanica, the medial centrale is always present. In both T. h. kazachstanica and T. h. hermanni carpalia increasingly fuse with age and size. The underlying morphological patterns differ however. The extreme character state in aged T. h. kazachstanica is one large solid bone element, formed by the fused intermedium, ulnare and both centralia. Aged T. h. hermanni have, in contrast, two separate larger carpal elements, one formed by the fused lateral and medial centralia and the other by the fused distal carpalia 1 and 2; the intermedium and ulnare never fuse with one another or with other carpalia. While a partial or complete loss of digit 1 seems to be characteristic for all Testudo species, we propose that the extensive fusion of carpal elements in T. horsfieldii is correlated with its natural history because a rigid manus could be advantageous for burrow-digging. Also the reduction of digit 4 (one phalanx present), a rare character among testudinids and not occurring in other Testudo species, could be linked with its mode of life. [ABSTRACT FROM AUTHOR]

We conducted a population genetic analysis of the two Amazonian tortoises, Chelonoidis denticulata (n = 40) and Chelonoidis carbonaria (n = 39) in a region of sympatry within the Xingú River basin. High levels of gene flow among sampled localities indicated lack of population structure for both species. Genetic parameters indicated a moderate level of genetic diversity in C. denticulata and neutrality tests suggested that populations of this species were in demographic equilibrium with respect to mitochondrial DNA. On the other hand, C. carbonaria presented low levels of genetic diversity and a signal of population expansion. Most records of C. denticulata are from areas of humid forest while those for C. carbonaria are from areas of semi-deciduous forests and transitional areas between humid and semi-deciduous forests. Therefore, the demographic expansion observed in C. carbonaria population could reflect an increase in the availability of suitable habitats for this species due to anthropogenic or natural processes. Additionally, we observed haplotype sharing between these two tortoise species indicating hybridization or incomplete lineage sorting. [ABSTRACT FROM AUTHOR]

The Amazonian tortoise, Geochelone denticulata, has been classified as vulnerable; nevertheless, necessary ecological and demographic information to formulate conservation plans is limited. In this study we present data on population density, habitat preference, diet and morphological measurements of a population inhabiting a lowland rainforest in Colombia. We used line transect methods to estimate population density over three different years, and we measured and marked 73 individuals in two additional years. The estimated population density based on 158 encounters was similar over the three years (41 ± 20, 38 ± 6, 34 ± 8 ind/km2 ±SE, respectively). However, we found marked differences between seasons within years, because it was easy to detect individuals (particularly males) during mating periods. There was no evidence of large scale seasonal migrations; thus, it is possible that individuals were missed in the non-reproductive season and therefore our figures may underestimate population size. For the same reason, sex ratios during the mating season may be more biased towards males than for whole year estimates (1.7:1 vs. 1.2:1). Monthly density estimates were significantly correlated with mating frequency and with estimates of fruit abundance, but were not associated with rainfall, temperature or sun radiance. These results suggest that males might use available energy from fruit to travel extensively during the mating season in search of females. However, the most productive forest type in terms of fruit was not preferred by tortoises, to the contrary, they were more commonly encountered in forests with a high proportion of gaps. Males tended to have larger and more elongated bodies than females. This result supports the hypothesis that since males must travel more in search of mates, it is an advantage for them to have an elongated carapace in order to move through dense understory. More ecological information is required from other geographical locations to establish which ecological variables are most important in determining the carrying capacity for terrestrial tortoises. So far the demographic structure of the populations suggest that predation of young individuals plays a major role. [ABSTRACT FROM AUTHOR]

We used geometric morphometric analysis to investigate latitudinal variation in size and shape of carapace and plastron of 111 Testudo hermanni hermanni (60 males and 51 females) collected in 6 different Italian regions. Basing on a sample of 14 landmarks for carapace and 18 landmarks for plastron, we showed that the size and shape of both sexes changed according to a North-South cline following the Bergmann's rule, tortoises of Northern Italy being 1.1-1.2 larger than that of Southern Italy. Shape variation was higher in carapace probably because sexual selection in this species acts stronger on plastron than on carapace shape. [ABSTRACT FROM AUTHOR]

Hermann's tortoise (Eurotestudo hermanni) from a mesic area of Central Italy (Isernia, Molise) was investigated during a two-year period (2003-2004). The population is characterized by a fairly high density when compared to other Italian and European populations, with density ranging from 16.16 individuals/ha in 2003 to 25.08 individuals/ha in 2004 (average density 20.84/ha). The sex ratio was 1:1 both in 2003 and 2004. Females were captured in higher percentages from May to July in both years, while males were most abundant from August to October. These differences can be related to the different needs and behaviour of males and females in the two periods, and to the environmental constraints of the study area. All the marked tortoises were found aged between 10 and 21 years. Adult males and females from the study area were small-sized when compared to those from other Italian and European populations. [ABSTRACT FROM AUTHOR]

The hyoid apparati of 25 geoemydid species in 16 genera (including aquatic, semiterrestrial and terrestrial taxa) are compared, and for Cuora galbinifrons bourreti ontogenetic development of the hypoid apparatus is described. Generally, ossification of the hyoid apparatus increases with age. The majority of terrestrial species maintain cartilaginous or partially cartilaginous hyoid bodies and second branchial horns throughout life however. Also in tortoises (Testudinidae) hyoid body and second branchial horns remain cartilaginous, suggesting a positive correlation between mode of life and hyoid morphology (terrestrial species with partly cartilaginous hyoid apparatus vs. aquatic species with fully ossified hyoid apparatus). [ABSTRACT FROM AUTHOR]

For the first time, inguinal palpation effectively detected calcified oviductal eggs in a tortoise species. Inguinal palpations for 36 Hermann's tortoises, from six samples during spring 1999 and spring 2000, were verified with X-ray radiography. Palpation results did not differ significantly from radiography results and did not differ between two independent observers. A logistic regression analysis indicated that palpation success depended on the presence of oviductal eggs, and not on observer, year (1999 or 2000) or tortoise age class (young adult or old adult). The probability of correctly classifying females as gravid or nongravid through palpation was 78.4%. Although inguinal palpation did not allow detection of all clutches, it is a simple, inexpensive and effective means to determine the breeding status of Hermann's tortoise populations. [ABSTRACT FROM AUTHOR]

Presents a study which examined the importance of radiocarbon dating for ancient DNA studies of native seychelles tortoises or Aldabra. Information on human-mediated transport of tortoise; Introduction of Aldabra tortoises to Curieuse and Fregate islands of the Seychelles as a conservation measure; Efforts to decipher the evolutionary origins of native Seychelles tortoises.

Growth ring counts on the shell have been widely used for age estimation in Chelonians. However, as stated by Wilson et al. (2003), most studies have applied this method without assessing its reliability by proving that 1 : 1 ratio between number of rings and real age exists. In the present study, the reliability of this method is analysed for a population of Hermann's Tortoise, Testudo hermanni introduced in the Ebro Delta (NE Spain). Age estimations were obtained from direct observations of tortoises in the field in 2000 (n = 82) together with those from photographs of the same and other individuals of the population taken between 1991 and 2001 (n= 356). A second photograph was taken at one or more years after the first one for 101 individuals. Results of Model II linear regression analysis indicated that the method was reliable only for tortoises between 0 and 7 years old, whereas tended to underestimate age for those between 8 and 11 years. Since, sexual maturity in this population is attained around 8 years (mean for both sexes), ring counts are only reliable for juveniles and subadults. Finally, it is noteworthy that the results coming for photographs were equivalent to those coming from direct observations in the field. [ABSTRACT FROM AUTHOR]

Hermann's tortoise (Testudo hermanni Gmelin) of the Island of Asinara (NW Sardinia, Italy) has been studied during a period of four seasons. This population consisted of several individuals of large body size, some of them being amongst the largest known for this species. Bony shells of males were commonly found on this island, while the same was not true for female bony shells. Although wild boars (Sus scrofa) are potential large sized predators for tortoises, the analysis of carapace morphology did not reveal injuries signs due to bites. Male tortoises could die due to up-turning, as the result of male-male combats during the mating season, to possible hyperthermia when upturned, and to predation carried out by birds particularly when upturned. Estimated density was 4.88 individuals ha[sup -1], which was similar to that of conspecifics from other areas studied so far. [ABSTRACT FROM AUTHOR]

We describe the behavioral adaptations of a population of Hermann's tortoise to the climate of a northern sector of its range, and to a wooded biotope that is uncommon for the species. The activity, the home range, and the thermal relations along the daily and the yearly cycle are described. In contrast to other populations that have bimodal activity peaking in spring and in autumn, the tortoises in our study area had unimodal seasonal activity that can be related to lower summer temperatures. Home range size, 7.4 ha for females and 4.6 ha for males in our study area, was from three to seven times larger than that of all other populations. The large home range, and the low population density of the tortoises in our study area, may be due to food scarcity in the wooded habitat. [ABSTRACT FROM AUTHOR]

Two tortoises, Testudo graeca ibera Pallas, 1814 and Testudo hermanni boettgeri (Mojsisovics, 1889), inhabit Bulgaria. Certain features normally used for their identification, such as division of the supracaudal scute (divided in T. h. boettgeri; undivided in T. g. ibera), are not absolute. Seven whole shells of T. g. ibera and eleven of T. h. boettgeri were studied, and also a large series of shell fragments of both species. Based on analysis of 44 shell characters, T. h. boettgeri was distinguished by the following: maximal width of vertebral scute V clearly greater than maximal widths of other vertebral scutes; width of vertebral scutes II, III and IV smaller than width of pleural scutes I, II and III; medial length of pectoral scute equal or slightly greater than half the medial length of the hypoplastron; hypo-xiphiplastral suture distant from the corner of the inguinal notch; medial length of xiphiplastron less than maximal width (in females), or nearly half the maximal width (in males). [ABSTRACT FROM AUTHOR]

Presents a study which examined a calamity for hatchling Moorish tortoises. Documentation of predation on hatchling and juveniles Testudo graeca; Behavior of soft hatchlings; Factors which are important to better understand the effect of landscape structure on the tortoise's space utilisation.