The purpose of this study was to determine the effects of short-distance nest relocation on nest parameters and embryonic development of loggerhead sea turtles (Caretta caretta). The nesting biology of the loggerhead sea turtle was studied on Blackbeard Island National Wildlife Refuge in 2005 and 2006 during the nesting season. Research nests were randomly assigned 1 of 2 treatments (in situ or relocated). In situ nests (n  =  35) were left in the original location, while relocated nests (n  =  34) were moved above the spring high-tide line and into areas that were considered to have favorable nesting conditions. Data-loggers were placed in the center of nests to record the temperature during incubation. Incubation durations, nest temperatures, hatch success, and hatchling straight carapace lengths were compared for all research nests. The observed nests showed similar nest parameters and embryonic development regardless of nest treatment. Differences in nest parameters and embryonic development seemed to be driven by abiotic conditions of the nesting site. This study shows that nest relocation can be used to alleviate nests of extreme abiotic conditions to increase hatch success, without altering embryonic development.

The flatback turtle is the only species of marine turtle that lacks an oceanic phase of development in its early life history. Instead, the turtles grow to maturity in shallow turbid shelf waters of tropical to subtropical Australia. We studied the development of diving behavior in neonate flatbacks to determine whether diving under those ecological conditions resulted in differences from leatherbacks (Dermochelys coriacea) and green turtles (Chelonia mydas) at the same age when diving in clear, deep oceanic waters. Data were obtained from flatbacks that varied in both age (1–7 weeks) and mass (38–100 g). Each turtle towed a miniature time–depth tag during a single 30-minute trial in shallow (≤ 12 m) turbid shelf waters near Townsville, Queensland, Australia. In total, 192 dives were recorded from 22 turtles from 4 nests. Most dives were short (< 100 seconds) and shallow (< 4 m), but even young turtles could dive to the bottom. The most common flatback dives had V- or W-profiles, whereas, in leatherbacks, most dives were V-profiles, and, in green turtles, the dives were either V- or U-profiles. Routine flatback dives were accomplished by swimming slowly (like leatherbacks), but, when sufficiently motivated, flatbacks could swim faster (> 1 m/s) than green turtles. They could also make repeated deep dives after surfacing only briefly to replenish their oxygen supply. Changes in performance (longer, shallower dives) were correlated with increases in mass but not age. We hypothesize that, as neonates, flatback dives enable the turtles to 1) search efficiently for prey throughout the water column under conditions of limited visibility, 2) minimize surface time so that even in murky water the turtles can return to previously attractive locations, and 3) swim rapidly to evade their predators.

The high probability of being depredated on the crawl to the water may have influenced the evolutionary processes of hatchling sea turtles on the beach. During this time hatchlings must locate water and move as quickly as possible in order to reduce the time spent on the beach. Hatchling leatherback turtles (Dermochelys coriacea) at Playa Grande, Parque Nacional Marino Las Baulas, Costa Rica, spent on average 34 minutes visible on the beach, covered a distance of 46.8 m, and moved at a rate of 3.11 m/min. During the time on the beach, 12% of hatchlings were eaten by predators, 83% reached the water, and 5% were determined as potential mortalities (hatchlings were stuck on debris, vegetation, or upside down). The main predators of hatchling leatherbacks at Playa Grande were ghost crabs (Ocypode occidentalis), great blue herons (Ardea herodias), and yellow-crowned night herons (Nycticorax violaceus) during the night, and crested caracaras (Caracara plancus) during the day. Tracks left by the hatchlings on the sand were straighter as they approached the water. Dispersion (distance between the 2 outermost tracks coming from a nest) was correlated with number of hatchlings crawling. Hatchling leatherback turtles at Playa Grande are threatened by predation by domestic animals. Hatchling mortality due to human-related activities is likely to increase in the future due to increasing pressure from tourism at Parque Nacional Marino Las Baulas.

The diving behavior of immature hawksbill turtles (Eretmochelys imbricata) was recorded by means of direct in-water observations during a period of 8 months over 4 years on a coral reef at D'Arros Island in the Seychelles. For 4 turtles that had become habituated, detailed behavioral observations were recorded and quantified during 148 contact hours during which 187 turtle dives were documented. Mean dive depth and duration were 8.2 m and 27.4 minutes, respectively. Surfacing intervals lasted on average 81.5 seconds and the mean number of breaths was 6.6 per surface interval. Dive duration was positively correlated with dive depth. On average, larger turtles conducted longer dives than smaller turtles and spent more time at the surface. Immature hawksbills at D'Arros averaged longer surface intervals and took more breaths than did those reported at other sites. We attribute this, at least in part, to the increased energy demands required to excavate cryptic food items at D'Arros. Although average foraging dives in this and other studies tended to be shallow (< 15 m) and short (< 30 minutes), the turtles are capable of significantly deeper and longer dives. We propose that immature hawksbills forage well below their physiological dive limits and do not strive to maximize their bottom times.

Stomach contents were obtained from 25 Hydromedusa tectifera and 47 Phrynops hilarii that live in syntopy in a pampasic stream in Buenos Aires province, Argentina. Both species are arthropod consumers. Copepods, ostracods, and hemipterans are the preferred items for P. hilarii, and H. tectifera prefers copepods, ostracods, immature dipterans (mainly chironomids), and ephemeropteran larvae. Items that most contribute to the diet of both species are immature chironomids, corixids, and belostomatids. Available food varies little among seasons, being slightly lower in winter months and part of the summer. Diet diversity changes by seasonal variation of prey item abundance in the diet of both species. Diet diversity is higher for P. hilarii (more generalist and broader trophic niche) than in H. tectifera, but there is no niche overlap between them. No significant correlation between the size of turtles and length of prey items was found. There is no evidence that the long neck of H. tectifera relates to piscivorous habits, because fish are a small fraction of its diet and arthropods constitute the bulk of the ingested items.

The varying influences of selective forces throughout a species' range can result in geographic variation in sexual size dimorphism (SSD). The Moroccan turtle, Mauremys leprosa, occupies an extremely wide variety of ecoregions and habitats, including coastal rivers, mountain streams, oases, and intermittent rivers in the northern fringe of the Sahara Desert. To assess geographic variation in SSD, we collected specimens along an environmental gradient in central Morocco, including Oued (River) Ksob on the Atlantic coast, Oued Zat in the High Atlas Mountain foothills, and Oued Drâa in the Sahara Desert. Only turtles with conspicuous secondary sexual characteristics were included in our analysis. We calculated a sexual dimorphism index (SDI) using the mean size of the larger sex divided by the mean size of the smaller sex and subtracted one from that ratio. The direction of SSD was biphasic: in one population males and females exhibited the same body size, whereas, in two other populations, females were larger than males. Mean straight-line carapace lengths of males and females were not statistically different at Oued Ksob (SDI  =  0.08), and females were relatively small. In contrast, females from Oued Zat were significantly larger than males (SDI  =  0.56) and females were larger than those from Oued Ksob. SSD was most dramatic at Oued Drâa (SDI  =  0.92) and much greater than any value previously reported for the species, with females exhibiting a mean carapace length greater than those in the other 2 rivers. A 2 × 3 factorial analysis of variance that compared the mean size of the sexes among the 3 sites yielded a significant SEX × LOCALITY interaction (p < 0.001), which demonstrated geographic variation in SSD. Geographic variation in SSD appears to represent the interaction of natural and sexual selection on growth rates and maturity schedules of males and females in different environments.

Herman's tortoise, Testudo h. hermanni, is an endangered subspecies in Italy, France, and Spain. We studied a Herman's tortoise population in the Riserva Naturale Regionale Monterano in the Tolfa Mountains of central Italy. We found that, unlike most other studies of this and related species, sex ratios were 1∶1, and half the population was made up of juveniles. Sexual maturity was reached at 12 years in males and 12–13 years in females, and females were significantly larger. Tortoises greatly preferred open maquis habitat over other habitat types and thermoregulated so that body temperatures stayed consistently above ambient temperatures, especially under low ambient temperature conditions. Presence of ticks was significantly associated with an index of thermoregulatory behavior. We suggest that maintenance of open maquis habitat in this reserve is essential to high hatchling production and effective thermoregulation.

The Texas tortoise (Gopherus berlandieri) is a state-protected, threatened species in Texas. The expansion of agricultural practices and urban development are major causes of habitat degradation for the species. To provide genetic data that can inform conservation planning for this species, genetic variation, population structure, and the process that maintains the observed structure were examined in the Texas populations of G. berlandieri. Microsatellite genetic variation of 8 polymorphic loci was examined for a total of 138 individuals collected from 10 sampling areas in southern Texas. Assignment tests, F statistics, and analysis of molecular variance indicated that G. berlandieri forms weak population differentiation into northern and southern groups, with a boundary at southern Duval County. A test of isolation by distance and indirect estimation of the number of migrants (Nm) suggest recent gene flow between the 2 groups. Estimation of the extent of contemporary migration appears to be complicated by human translocation of tortoises, and an asymmetrical direction of migration needs further examination. Gopherus berlandieri is weakly differentiated because of ongoing migration as evidenced by a pattern of isolation by distance. Given the limited population structure and continuous habitat degradation, designation of 2 management units may not be warranted. Conservation efforts, rather, should emphasize connectivity between the groups to maintain genetic variation in both groups.

We studied various aspects of the reproductive biology of the Magdalena River turtle (Podocnemis lewyana) during 2 nesting seasons in 2 locations in the Mompos Depression in northern Colombia. We monitored 53 nests; 22 that completed incubation in situ, 24 that were transferred to protected areas (transferred nests), and 7 that were constructed using eggs removed from females that had been consumed by local people (“oviductal” nests). For each nest, we registered the oviposition date, distance to the nearest body of water, soil type, vegetative cover, exposure to sunlight, depth to the first egg, and maximum depth of the nest chamber. We also quantified egg dimensions and clutch sizes, mean incubation temperatures and duration of incubation periods, hatching success rates, and sex ratios. Most nests were located within 15 m of the shoreline, in open or grassy areas with permanent exposure to sunlight, and in sandy soils. The 3 nest types (natural, transferred, and oviductal) did not differ in hatching success rates. In both seasons, the majority of the nests produced hatchlings of both sexes, but the sex ratios differed between the nesting beaches and seasons. Incubation temperatures influenced incubation periods and hatching success rates, but not hatchling sizes or weights. The management implications of the findings are discussed.

Podocnemis expansa (the giant South American or arrau turtle) is a freshwater turtle in critical risk of extinction, distributed along the Orinoco, Amazon, and Esequibo river basins. Protection of nesting beaches and headstarting of hatchlings has been in progress since 1989 on the Arrau Turtle Wildlife Refuge located in the Middle Orinoco River in Venezuela. The purpose of our study was to evaluate the population dynamics of the species in this refuge. We used data on the number of turtles and number of nests collected from 1989 to 2004 that were available from the Venezuelan Ministry of Environment as well as data collected by us in 2004. Also, we collected data in 2004 on sizes of individuals of known age. First, a somatic growth curve was constructed and used to transform size structure in age structure. Age-specific fecundity and survivorship were calculated. Finally, we constructed a size-dependent matrix model and used it to determine population status and to assess the effectiveness of alternative management options. According to our analyses, the population size and age structure have stabilized. The analyses also indicate that protecting the survivorship of juveniles and adults, more than fecundity, is the conservation action that could best reverse a population decline. We conclude that additional efforts focused on protecting juveniles and adults of the arrau turtle, such as reinforcement of illegal hunting controls, must be implemented in order to ensure the success of the conservation program.

Alimentary habits are critical to the ecology of all animals. They reflect resource availability and are correlated with important life history traits such as reproductive output and body size. We analyzed the diet of the previously unstudied Mexican mud turtle Kinosternon integrum at Tonatico, Estado de México, during 2003 and 2004. Analysis was conducted separately by sex and age (immature vs. adults) and seasons (rainy vs. dry). Gastric contents and fecal samples were used in combination for more complete results. Based on 57 samples (32 stomach flushes and 25 from feces), K. integrum is a generalist–opportunist in alimentary habits, feeding on 27 categories of food. Plant material, Coleoptera, Odonata, Diptera, and mixed animal matter were the most important components. Overall dietary diversity was similar between adults and juveniles and between the two sexes, but juveniles differed between seasons. In similarity analysis we found a shift in diet between seasons. Females shifted from being primarily carnivorous during the rainy season to being primarily herbivorous during the dry season, while males were carnivorous during both seasons. The data suggest that this turtle feeds opportunistically on available prey items rather than on a few preferred food items.

Cryptic or undescribed species pose a major problem in conservation biology. Managing multiple unresolved taxa collectively as a single entity could precipitate the loss of unrecognized genetic variation and unique populations and, possibly, lead to extinction of undiscovered or unrecognized taxa. In contrast to other species in its clade, the Pascagoula map turtle (Graptemys gibbonsi), as currently recognized, is not confined to a single major river system (or a cluster formed by a major river and adjacent minor drainages) but occurs in two major river systems, the Pearl and Pascagoula Rivers. We analyzed G. gibbonsi samples from both rivers for the first time in a morphological and molecular assessment of the taxonomic status of this poorly studied species. We compared the extent of genetic differentiation (mitochondrial DNA; mtDNA) between G. gibbonsi populations with members within the pulchra clade and between Graptemys oculifera and Graptemys flavimaculata. We found significant carapace pattern variation and morphological differentiation between the Pearl and Pascagoula river samples of G. gibbonsi. Our mtDNA sequences showed greater genetic differentiation between G. gibbonsi samples from the Pearl and Pascagoula rivers than between two recognized and reciprocally sympatric species, G. oculifera (Pearl River) and G. flavimaculata (Pascagoula River), but revealed only a modest degree of differentiation when compared to other members of the pulchra clade. Based on the degree of differentiation in 1) morphology, 2) color patterns, and 3) mtDNA, in addition to their 4) allopatric distributions, we describe a new species from the Pearl River, restricting the species G. gibbonsi to the Pascagoula River.

The Arakan forest turtle (Heosemys depressa) is a critically endangered, poorly known chelonian endemic to western Myanmar. We conducted surveys of the Rakhine Yoma Elephant Range in 2003 and 2009, and herein report field observations of H. depressa. This protected area offers excellent prospects for the future conservation of this endangered species owing to its large area, inaccessibility, and minimal human activity.

Nesting of Chelonia mydas and Lepidochelys olivacea in Pakistan occurs at Hawkesbay and Sandspit along Karachi Coast and at Ormara and Jiwani along Balochistan Coast. During the present study, we surveyed all known and potential turtle nesting sites and identified 6 new nesting beaches, including Mubarak village (Karachi Coast), Gwadar (West Bay), Pishukan, Ganz, Sonmiani, and Hingol National Park (Balochistan Coast). During the study we observed that habitat degradation constitutes a major threat at coastal areas near Karachi and Korangi creeks.

This study investigated the sex ratio of leatherback turtle hatchlings along the Huon Coast, Papua New Guinea, from January to March 2007. Results show that this population predominantly produces male hatchlings throughout the peak of the nesting season. The long-term decline of leatherback nesting along the Huon Coast, in conjunction with the highly male-biased sex ratio, presents serious challenges for the management and recovery of the western Pacific leatherback meta-population.

During a study of an Iberian population of the European pond turtle, Emys orbicularis, a very high number of water lily seeds, Nymphaea alba, was found in fecal samples. Further analysis of additional samples collected between 2003 and 2008 indicated that E. orbicularis uses water lilies as an emergent food resource during summer. It is proposed that E. orbicularis should no longer be viewed as strictly carnivorous.

Anthropogenic factors can negatively impact wildlife populations, but deleterious effects may not be universal. We investigated the relationship between nest predation and spatial proximity to anthropogenic structures (campsites, trash bins, etc.) for 1375 painted turtle (Chrysemys picta) nests over 6 years for a population on the Mississippi River, Illinois. Although varying among years, the probability of nest predation increased with greater distance from anthropogenic structures over all years combined and did not differ between supplemental food attractant structures (e.g., fish cleaning table) and nonsupplemental food attractant structures (e.g., horseshoe pits).

Investigation of the total of 53 juvenile sea turtles (30 green turtles and 23 hawksbill turtles) found signs of several clinical diseases. Ultrastructure and histological observation of these tissues revealed that they were infected with one type of yeast and numerous bacteria. Using aerobic microbiological culture techniques, 10 types of Gram-positive and Gram-negative bacteria were identified, which may be responsible for disease and subsequent death of juvenile sea turtles at the conservation center.