Like many fragmented reptile populations, the ornate box turtle (Terrapene ornata ornata) is located in isolated, often small, populations in eastern Iowa. If populations are to remain viable, genetic diversity within these populations must be maintained, which is done most efficiently by migration among populations. Population viability was accessed using 3 microsatellite loci to determine population genetic structure in 2 locally dispersed subpopulations of ornate box turtles. Although these subpopulations were determined to be 1 large population with the normal range of heterozygosity, further examination revealed evidence of genetic divergence from a once larger population that is now geographically separated into fragments. We concluded that the central population studied was genetically healthy, and with proper management that continues to promote gene flow, the population should remain viable in the near future.

We studied reproductive ecology and egg survivorship of Podocnemis erythrocephala (Spix 1824) in 4 campina habitats on the Ayuanã River, Santa Isabel do Rio Negro, Amazonas, Brazil. There were 2 nesting periods, the first in early October and the other in the beginning of December, separated by a period of flash floods. A total of 117 nests were recorded, with a nest density of 19.9 nests/ha, a mean clutch size of 8.7 eggs, and a mean egg volume of 14 cm³. Females chose to nest in the most open sites, with plant cover of up to 50%. Nest loss reached 100% for the season: 70% was from flash floods, 12% was from predation by the weasel Eira barbara (Mustelidae), 9% was by the lizard Ameiva ameiva (Teiidae), 5% by humans, 2% by Crocodilurus lacertinus (Teiidae), and 1% by Daptrius ater (Falconidae).

In most animal species, it is expected that females should exhibit a greater abdominal volume than males to hold the progeny, when compared with females, males should exhibit more developed attributes that enhance mobility. We tested this hypothesis in the Greek tortoise. In chelonians, a reduction of the openings in the shell improves protection against predation but also constrains the abdominal volume and limits the space available to move the limbs. As expected, our data show that the shell provides a larger abdominal volume relative to tortoise size in females than in males. In males, deep notches in the shell and a reduction of several plastron plates offer more freedom to the limbs and to the tail; these characteristics presumably enhance mating success. Further studies are necessary to assess the applicability of these results in other chelonians, notably freshwater and marine turtles.

Commercial exploitation of freshwater turtles and tortoises has increased significantly in China since the 1990s, which has expedited the listing of some turtle species in Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix II. We assessed the risk to tortoises and freshwater turtles native to China by analyzing biological and socio-economic variables. The Principal Component Analysis model with VARIMAX rotation was used to categorize these species into groups. We found that many turtles in significant trade are at high risk of overexploitation. Except for Pelodiscus sinensis and Mauremys reevesii, most tortoises and freshwater turtles are classified in the same group and have similar risks. Listing several (but not all) chelonian species in the CITES Appendices will not resolve the chelonian trade crisis because many species may be substituted in trade. We recommend listing more Chinese turtles in the CITES Appendices.

We studied distribution, habitat selection, and reproductive ecology of the Magdalena river turtle, Podocnemis lewyana, from January to June 2003 and from January to March 2005 in the mid and low Sinú River, Córdoba, Colombia. The southern limit of its distribution occurs in the town of Carrizola, and the northern limit is near La Doctrina. We found more turtles of bigger size classes in the mid basin than in the low basin. Ninety-two individuals were observed basking in the river. Larger turtles were mostly observed in deep pools (> 3 m) with loamy or sandy bottoms, with easy access to basking sites, such as riverbanks, fallen trees, or beaches, and in areas with all types of shoreline vegetation but especially with riparian forest. Smaller turtles were found in colder, shallower, and more turbid waters than were adults, mainly in areas without riparian forest or in pastures with few trees, usually hidden in pastures flooded by the river. Adults ventured farther from shore than did juveniles. Along the study area, 5 nesting beaches were located: 3 in the mid basin and 2 in the low basin. Main nesting sites were sand and gravel beaches, but riverbanks were also used. Nesting occurred in small groups or individually in 2 reproductive seasons: one from December to March and the second from June to August. The main threats identified for P. lewyana in the Sinú River were floods caused by water release by Urrá Dam, human consumption and exploitation, nest damage caused by beach mining, and riparian forest destruction for pasture establishment.

We obtained evidence of the continued presence of Podocnemis lewyana in 18 different sites within the Magdalena River drainage of northern Colombia. However, abundances at most sites were low, even in areas where the species had previously been reported as common. Although hunting of adults is no longer commercially viable, local people consume individuals that are captured incidentally while fishing. Hunting of eggs during the incubation period each year continues to be intensive. Turtle abundances were negatively related to human densities throughout this area. In the Chicagua River, where turtle abundances were highest, we conducted standardized shoreline censuses of basking adults and documented abundances of approximately 6 individuals/km². Turtles often basked on mud banks, beaches, or emergent logs in aggregations made up of all size classes. Pilot trapping efforts also succeeded in capturing all size classes of turtles, which suggests that more intensive monitoring programs would be feasible. Given the evidence of declines in most areas of the range of this species, the current lack of regulation of its exploitation, and the projections for continued human population growth in this area, we recommend its International Union for Conservation of Nature (IUCN) status be changed from Endangered to Critically Endangered (CR A2acd).

We studied the effects of timing and placement of eggs by gravid desert tortoises, Gopherus agassizii, on sex ratios and potential survival of hatchlings. We monitored nest placement by female tortoises under seminatural conditions at the Fort Irwin Study Site (FISS) in the Mojave Desert, San Bernardino County, California, United States, and under wild conditions in habitat surrounding FISS. We located 16 nests and found no significant difference between nest placement in the seminatural enclosure at FISS and nest placement in the wild. Gravid females deposited their eggs down the tunnel a mean distance of 0.7 m and buried their eggs at a depth of 8–10 cm from the soil surface. Utilizing this preliminary nesting data, we set up a manipulative experiment to further characterize the effect of nest site and date on sex ratios and survivorship of hatchlings. We constructed 14 egg nests and 9 pseudo-nests in the FISS enclosure and monitored incubation temperatures and resulting hatchling sex ratios. Forty-seven hatchlings emerged (79% survivorship) and 33 were positively sexed. Nests placed early in the reproductive season produced 6 all-female nests and nests placed late in the season produced 4 all-male nests. The mean incubation period was 90 days, which we divided into 3 time periods. Early nests were significantly cooler than late nests during the first and second time period (days 0–30 and days 31–60) and significantly warmer during the third time period (day 61–90). The shallowest pseudo-nest, located 0.2 m down the burrow tunnel, spent a significantly greater time above the critical temperature of 35.3°C than did the 0.4 m pseudo-nest or the egg nest. We hypothesize from these findings that females at the FISS site and surrounding area are selecting distances down the burrow tunnel to lay their eggs that increase the embryos' chances of survival. We found that the proportion of temperature observations above the pivotal temperature (35.3°C) during days 15–45 was a better predictor of hatchling sex than the proportion measured during days 30–61. Using nest date or the proportion of temperature observations above the pivotal temperature as predictors of hatchling sex ratios may be possible for desert tortoises in the Central Mojave Desert.

Sex ratios for hatchlings and adult turtles collected in aquatic habitats were examined for red-eared sliders (Trachemys scripta elegans) collected at Long Lake in west-central Illinois. We found that sex ratios were initially balanced but became progressively more male biased with the passage of time. Large cohorts of newly recruited males seem to underlie the increasing male bias. Recruitment more than doubled between 2001 and 2004, and these turtles were strongly male biased. Climatic warming may have led to the current male bias. A period of warming at the site has allowed females to lay more eggs by lengthening the nesting season. Females are laying an extra clutch, which accounts for the increased recruitment. This clutch is laid when soil temperatures are relatively low, explaining the male bias in newly recruited turtles. The impact of the increased number of male turtles on the population is uncertain. However, female condition declined about 7% between 1994 and 2006, suggesting that an effect may be occurring.

The turtles of the Caucasus are poorly studied, and basic data on their geographic distribution in some Caucasian regions are poorly collated, hard to access, or entirely lacking. We present a comprehensive review of turtle localities in such a region, Armenia and Nagorno-Karabakh Republic (Artsakh), based on literature records, personal observations, and museum specimens. The compiled data for the 3 native species (Emys orbicularis, Mauremys caspica, and Testudo graeca) show that their distributions in this region are restricted to 3 areas of low elevation. In the northeast, turtles can be found in the Kura River drainage. In the south and west, turtles can be found in the Arax River drainage. The distributions of species within these areas vary, with E. orbicularis being the most restricted by elevation. We note that the 3 regions here form part of an important transect from the interior Arax drainage (in the Ararat region of western Armenia) to near its confluence with the Kura drainage (in southern Armenia and Nagorno-Karabakh) to the Kura drainage sensu stricto (in northeast Armenia). Future studies of turtles in these areas will play an important role in understanding the historical biogeography of Caucasian turtles.

In the Seychelles islands, all 3 endemic freshwater turtle taxa are either extinct (Pelusios seychellensis) or critically endangered (Pelusios castanoides intergularis and Pelusios subniger parietalis). These turtles are threatened by habitat loss, and monitoring of populations since 1996 has identified significant ongoing population declines. Drainage of wetland sites has reduced the number of populations, but even surviving sites are mostly reduced in area and quality. Only 5 Pelusios subniger parietalis and 3 Pelusios castanoides intergularis populations showed evidence of reproduction within the last 10 years. Longevity records suggest that Pelusios species may live for at least 40 years, and captive breeding data indicate that sexual maturity may be comparatively early in these taxa (ca. 2 years). Populations can persist for decades after reproduction has ceased, resulting in effective population extinction, even when environmental conditions stabilized. This is a characteristic that is shared with other long-lived species, and demography should be an essential component of recovery plans for any such species. Conversely, improvement in habitat may allow rapid population recovery, as has been demonstrated in Pelusios subniger parietalis on Fregate Island.

The species-level designation of the Mexican softshell turtle, Apalone atra, has been repeatedly challenged, yet no DNA evidence has been collected. We conducted field studies of all the drainages of the Cuatro Ciénegas basin, and the only pure morphological population of A. atra found was in Tío Candido, the type locality for the species. One nuclear intron known to show species-level divergence in the family Trionychidae, 2 nuclear genes, and a mitochondrial gene revealed little molecular divergence for A. atra when compared with A. spinifera emoryi from the Rio Grande. Further, no reciprocal monophyly of the mitochondrial gene tree was seen between A. atra and A. s. emoryi morphotypes.

Over a 3-year period, we studied the relationship between the intensity of human recreation and the nesting ecology of the painted turtle (Chrysemys picta) at a major nesting beach. Our results suggest that the intensity of human recreation at this site had no effect on the decision of turtles to emerge from the water and nest, or on habitat selection by nesting turtles. This apparent lack of effect of human recreation is contrary to the results of many previously published studies on other taxa and underscores the variability in wildlife responses to human recreation and the need for species-specific and population-specific studies.

A mark-recapture project on Macrochelys temminckii was conducted between 1997 and 2000 at Sequoyah National Wildlife Refuge, Muskogee and Sequoyah counties, in eastern Oklahoma. Turtles were captured in all streams and exhibited equal sex ratios, marked sexual-size dimorphism, and population densities between 28 and 34 animals per km stretch of stream. There was evidence of past population perturbations, with very few large adults captured, and a cohort of subadults highly underrepresented.

Between March and May 2003, the leatherback turtle (Dermochelys coriacea) nesting population of the Pacuare Nature Reserve (northern Caribbean coast of Costa Rica) was surveyed for potential bacterial pathogens associated with the cloaca and upper respiratory tracts. A total of 189 isolates that belong to 15 genera, including 113 gram-negative and 76 gram-positive bacteria, were identified from samples of 70 nesting females. The majority of the bacterial species recovered in this study, including 5 Salmonella isolates, may be considered as potential pathogens for sea turtles, as well as for humans.

Relative abundance of the Travancore tortoise, Indotestudo travancorica, was assessed in 5 localities within the Indira Gandhi Wildlife Sanctuary, India, from December 2002 to March 2003. Relative abundance varied with site and season, but the overall mean search effort for this study was only 3.4 man-hours/tortoise. Morphometric data were collected from 49 adults and 3 juveniles; sexual differences in carapace shape (elongated in males, ovoid in females) and variations in carapace color (darker in mesic habitats) were also observed.

Hatchling Glyptemys insculpta did not travel to water directly upon emergence from their nests but remained in agricultural fields for several days to weeks, during which time they fed and grew. Hatchlings were less active and occupied sites with significantly lower air and substrate temperatures than adult turtles. A management scheme to delay agricultural harvesting until turtles have entered aquatic habitats for hibernation is advised.

Food acquisition, feeding, and growth in moist terrestrial laboratory conditions were compared in 2 species of turtles that inhabit brackish water environments. Malaclemys hatchlings showed normal growth, but Chelydra hatchlings became severely stressed. The results suggest that the extended use of terrestrial habitats as a means of osmoregulation in high salinity habitats is a viable adaptive strategy for diamondback terrapin but not for snapping turtle hatchlings.

Tortoises are the group of reptiles most under threat in Namibia and are poorly researched, with little understanding of their basic ecology. This paper investigates some aspects of the ecology of female Bushmanland tent tortoises (Psammobates tentorius verroxii) in southern Namibia, specifically their movement, home range, activity pattern, diet, resting site selection, and orientation.

Between 1997 and 2001, we observed nesting behavior following oxytocin-induced oviposition in 10 three-toed box turtles. Oviposition preceded nesting behavior by 0.5–17 days. Three turtles oviposited subsequent clutches (without oxytocin induction) a mean of 30 days after the oxytocin injections but only 22 days after they constructed empty nests. The mean internesting interval was 21 days between consecutive ovipositions without oxytocin induction by these 3 females in the same and subsequent seasons.

Between 2002 and 2005, we used drift fences and artificial pools to sample juvenile eastern box turtles (Terrapene carolina) in northeastern Alabama in forest stands experimentally treated to retain various amounts of overstory trees—clear-cuts and those with 25%–50% and 75%–100% of trees retained. We captured juvenile turtles only in clear-cut and 25%–50% retention plots; microhabitats in these plots are characterized by a combination of abundant vegetative ground cover and leaf litter.

The phylogenetic relationships among taxa within the emydid genus Trachemys have largely remained unresolved. A 768-basepair fragment of ND4, as well as the histidine, serine, and leucine tRNAs were sequenced from 18 of 26 of the extant species and subspecies of Trachemys. The aligned sequences were analyzed using maximum parsimony, maximum likelihood, and Bayesian methods. The results support the taxonomy of the genus as proposed by Seidel.

We examined the diet of Amyda cartilaginea from 2 localities in Sarawak: Loagan Bunut National Park and Balai Ringin. The most commonly found items in stomach contents, when using percentage frequency of occurrence, were plant material (77%) and unknown vertebrate parts (55%). Fecal analysis indicated similar results: plant material (100%), unknown vertebrate parts (84%), fish (69%), and unknown arthropods (62%). Results indicate that A. cartilaginea is an opportunistic omnivore.

We documented differential blood cell counts and plasma polypeptide profiles in Testudo graeca and T. horsfieldii raised in captivity in Lebanon, and investigated bioactivity of T. graeca plasma against a human colon cancer cell line (HCT-116). The percentage of red blood cells, thrombocytes, heterophils, basophils, lymphocytes, monocytes, and eosinophils did not differ significantly between the species during winter or spring. The total number of plasma polypeptides differed between the species, with 2 additional polypeptide bands in T. horsfieldii. Plasma from T. graeca significantly affected the percentage proliferation and percentage viability of human cancer cell line HCT-116.