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Determining activity rhythms is crucial for understanding the life history, ecology, and evolution of an animal species. Due to various anthropogenic threats, wild populations of Reeves' turtle (Mauremys reevesii) are diminishing throughout its geographic range in East Asia. Despite the endangered conservation status of this species, little is known about its activity rhythm. Therefore, the focus of this study was to radio track 23 wild Reeves' turtles in the field to determine their daily and seasonal activity patterns. We identified the Reeves' turtle as both diurnal and nocturnal, rather than the traditional classification of diurnal, with an average daily activity peak between 1800 and 2000 hours. In spring, the frequency of diurnal activity was higher than that of nocturnal activity, and males were significantly more active than females. In summer, total activity frequency increased significantly and was predominantly nocturnal, with no significant difference in activity found between males and females. In autumn, nocturnal activity decreased and males were significantly more active than females overall. Reeves' turtles hibernated from the end of October to mid-April. Our results elucidate the daily and seasonal activity rhythms of Reeves' turtles, thus providing a reference for understanding the life history of the species and potentially improving future conservation planning. [ABSTRACT FROM AUTHOR]

Knowledge about the distributions of species and the variables influencing their occurrence is important for their management and conservation, but factors affecting occurrence can vary across the range of a species. Northwestern pond turtles (Actinemys marmorata) are widespread generalist turtles, but are nonetheless of conservation concern throughout their range. To better understand the distribution of northwestern pond turtles and introduced American bullfrogs (Lithobates catesbeianus), we surveyed streams on private timberlands of the interior foothills of northern California using visual encounter surveys and collecting samples of environmental DNA. We found that northwestern pond turtle occurrence was negatively related to elevation in our sampling frame. Detection probabilities with environmental DNA were approximately twice those of visual encounter surveys, but both methods were effective for detecting turtles in streams. American bullfrogs were detected in a single sample at each of 2 sites (one by environmental DNA, one by visual encounter surveys). Management for northwestern pond turtles in forest streams within our sample area will likely have the largest effect at lower elevation sites where turtles are most likely to occur. [ABSTRACT FROM AUTHOR]

Many freshwater turtles in the United States are considered species of greatest conservation need in the states in which they occur, including turtles in the genus Graptemys (map turtles and sawbacks). However, basic life-history information is still lacking for many Graptemys species, particularly details about their movements, home range, and habitat use. The objective of this study was to describe linear activity area (LAA) and basking-site fidelity for 2 federally threatened Graptemys species in Mississippi (Graptemysflavimaculata, Graptemys oculifera) via capture–mark–recapture events. For G. flavimaculata, 97 individuals (30 female, 67 male) were recaptured during the study at 3 sites. Mean LAA for females (138 ± 293 m; 0–1489 m) and males (308 ± 637 m; 0–3773 m) was statistically similar, but turtle LAAs from 2 upstream sites were longer than LAAs from a downstream site. The maximum single movement was 2877 m by a male; alternatively, many males and females were recaptured at the same basking log across multiple years. For G. oculifera, 28 individuals (14 female, 14 male) were recaptured during the study at 1 site and mean LAAs were statistically similar for females (130 ± 206 m; 4.6–747 m) and males (231 ± 357 m; 0–1310 m). Differences in LAAs among sites for G.flavimaculata may be associated with habitat differences observed among the sites (i.e., river size, hydrology, position on river continuum) or associated with different turtle densities. Basking-site fidelity appears to be strong in both species and is likely driven by deadwood persistence time and/or sexually divergent preferences in basking sites. Additional movement ecology studies are needed for Graptemys species to determine how differences in habitat, turtle densities, and deadwood interact to influence linear home ranges. [ABSTRACT FROM AUTHOR]

In the first range-wide population viability model for the northwestern and southwestern pond turtles (Actinemys marmorata and Actinemys pallida, respectively), a stage-based population projection matrix was assembled with 3 life stages: hatchling, juvenile, and adult. Vital rates were defined using biologically appropriate statistical distributions, with additional parametric uncertainty included for the adult survival parameter. A triple-loop stochastic simulation model was built around a population viability analysis to project pond turtle populations into the future. Initial abundance was calculated using available historical presence data and remotely sensed landscape condition metrics. A negative binomial regression was used to predict the relationship between abundance, habitat area, and human modification. Populations of pond turtles are dominated by adult individuals, so we applied a nonstable stage distribution to initial abundance values. Initial abundances of analysis units were variable across the species' ranges, but all populations declined precipitously in the population projections. By the end of the century, the mean range-wide probability of extinction was 44.3% for the northwestern species and 57.8% for the southwestern species. Consistent with other long-lived chelonian species, population growth rate was most sensitive to adult survival, indicating that where possible, conservation efforts focusing on increasing or maintaining adult survival would benefit the species. Elasticity analysis indicated a bet-hedging life history strategy where long-term reproductive output is maximized through longevity, small clutches, and frequent reproductive bouts in the face of highly variable juvenile survival. The population dynamics presented here indicate that efforts to bolster adult survival would be most beneficial in terms of long-term population viability, which can inform targeted research and management. The feasibility of such efforts is an important consideration in conservation management for these long-lived species. [ABSTRACT FROM AUTHOR]

The Scorpion Mud Turtle (Kinosternon scorpioides) has been recognized by most recent authors to be a single species (3 subspecies) ranging from Tamaulipas, Mexico, to northern Argentina. However, recent molecular analyses have demonstrated that it is not monophyletic, but rather paraphyletic relative to other Neotropical Kinosternon. Based on extensive genetic sampling across the range of this species, a recent paper elevated the 3 subspecies (albogulare, cruentatum, and scorpioides) to species status, confirmed the divergence of Pacific and Atlantic versant populations of K. cruentatum, and recommended that both be given species status. However, the type locality of K. cruentatum is imprecise, making the allocation of the name problematic. Our study sought to determine the provenance of the type using morphometric analysis of specimens from across the range. That analysis demonstrates unequivocally that the type of K. cruentatum was collected on the Atlantic versant, likely from an eastern population. Furthermore, the analysis also revealed that the type of K. mexicanum, previously synonymized with K. cruentatum, was collected from along the Pacific versant. Hence, the name K. cruentatum should be restricted to populations in Atlantic drainages, and the name K. mexicanum should be restricted to Pacific drainages. Our analysis also indicated divergence among the 3 allopatric Atlantic versant populations, but future genetic work will be needed to determine whether they merit taxonomic recognition. [ABSTRACT FROM AUTHOR]

The savannah side-necked turtle Podocnemis vogli is a species restricted to the savannas of the Orinoco basin in Colombia and Venezuela. Because of its apparent abundance, it is currently categorized as Least Concern (LC) by the IUCN Red List. However, throughout its distribution range, several populations have been extirpated or individuals in remaining populations are consumed and trafficked, and the species' habitat has been highly degraded. To start assessing the conservation status of the species, 5 populations along their distribution range in Colombia were analyzed using 19 microsatellite loci to perform a population genetics study. Ten of those markers were useful in revealing (1) high levels of genetic diversity, (2) a marked genetic structure of 5 populations, and (3) low and asymmetric gene flow among them. However, the analyses also revealed the loss of genetic diversity (low allelic richness) and recent bottlenecks in some populations. Those identified detrimental indicators are evidencing a population decline most likely related to anthropic activities. These 5 populations correspond to 5 independent management units. The results of this research allow us to propose management and conservation guidelines for these populations in the Orinoco ecoregion. Resumen La tortuga sabanera Podocnemis vogli es una especie restringida a las sabanas de la cuenca del Orinoco en Colombia y Venezuela. Debido a su aparente abundancia, actualmente está categorizada como en Preocupación Menor (LC) por la Lista Roja de la UICN. Sin embargo, a lo largo de su rango de distribución, varias poblaciones han sido extirpadas o los individuos en poblaciones remanentes son consumidos y traficados, y el hábitat de la especie se ha degradado intensamente. Para comenzar a evaluar el estado de conservación de la especie, se analizaron cinco poblaciones a lo largo de su rango de distribución en Colombia utilizando 19 loci microsatélites para realizar un estudio de genética poblacional. Diez de esos marcadores fueron útiles para revelar: (1) altos niveles de diversidad genética, (2) una estructura genética marcada de cinco poblaciones y (3) flujo de genes bajo y asimétrico entre ellas. Sin embargo, los análisis también revelaron la pérdida de diversidad genética (baja riqueza alélica) y cuellos de botella recientes en algunas poblaciones. Esos indicadores perjudiciales identificados están evidenciando una disminución de las poblaciones, muy probablemente relacionada con las actividades antrópicas. Estas cinco poblaciones corresponden a cinco Unidades de Manejo Independientes. Los resultados de esta investigación nos permiten proponer lineamientos de manejo y conservación para estas poblaciones en la ecorregión del Orinoco. [ABSTRACT FROM AUTHOR]

Understanding which factors make an individual susceptible to parasitism provides insight on how a parasite infects a host. Numerous factors such as habitat characteristics, body size, and sex have shown differential impacts on parasitism rates. Trends in parasitism rate often exist for similar taxonomic groups, so expanding research to new species helps test the robustness of such trends. A chelonian-specific ectoparasite, Cistudinomyia cistudinis (Diptera: Sarcophagidae), has been documented in case studies dating back a century. Almost all reports of infection by this flesh fly are of a single or few turtles, so there is a lack of information regarding the population dynamics of infection. This lack of information means little is known about which factors make a turtle more or less likely to be parasitized. In this work, we compared the occurrences of parasitism in ornate box turtle (Terrapene ornata) populations across multiple seasons from 2 different habitats in northeastern Kansas (North Topeka and Lawrence). At the population level, we found a significantly higher number of parasitized turtles in the Lawrence population. Within the Lawrence population, we found females were more likely to be parasitized. This study sets baseline infection rates for a long-lived vertebrate host that can help better understand the reasons for parasitism both among and within populations. [ABSTRACT FROM AUTHOR]

All monitoring programs on the west coast of Australia have trialed a new mark–recapture protocol to address tag loss in individual flatback turtles (Natator depressus) during recent nesting seasons (2020, 2021, 2022). This protocol aligns with ethical considerations for the tagging of marine megafauna. In addition to increasing retention rate of identification tags, this new protocol is expected to decrease the potential long-term health impacts of tagging on this species. [ABSTRACT FROM AUTHOR]

With populations declining across their geographic range, the spotted turtle (Clemmys guttata) is currently a species of conservation concern. Though broadly distributed, the species is particularly enigmatic at its southern periphery, and many aspects of its ecology and population biology in this portion of the range have either just recently been described or are currently unknown. One of the current knowledge gaps is a robust assessment of the population genetics of the southern populations. We collected tissue samples from 204 spotted turtles from 5 sites across South Carolina, Georgia, and Florida and used 11 microsatellite loci to investigate the genetic diversity and population structure in these populations. We found that southern populations exhibited low, but significant, population differentiation (mean FST = 0.062) and each site clustered as its own genetic group. Genetic diversity across sites was comparable to estimates reported for northern populations. Net effective population sizes were generally robust and no populations showed indication of recent bottlenecks. Our results suggest that populations inhabiting relatively intact environments do not appear to face immediate threats from past loss of genetic diversity. However, continued monitoring, both demographic and genetic, of this long-lived species is an important management goal to insure that continued global changes do not threaten population viability. [ABSTRACT FROM AUTHOR]

Effective management of a species requires that resource managers know critical aspects of its ecology, including information on home range and habitat use. We conducted the first telemetry study on the Suwannee alligator snapping turtle (Macrochelys suwanniensis), and we examined movements at an upper river (UR) site and a lower river (LR) site in the Suwannee River in Florida, USA. We estimated home range size with kernel density estimates (KDE) using the FishTracker GIS toolbox, and we examined potential differences in KDEs with Generalized Linear Models (GLMs). We also used GLMs (family = binomial) to examine habitat selection for M. suwanniensis. We used an information-theoretic approach to rank and select the most parsimonious models. Overall, our models revealed that M. suwanniensis possessed larger 90% KDEs in the LR site than the UR site, and in both sites, turtles moved into the floodplain during flooded conditions. Remarkably, these movements continued even after water levels receded and the aquatic links were severed. Interestingly, M. suwanniensis selected shallow water with some type of subsurface cover, especially large woody debris (LWD). Instream LWD is likely extremely important, especially during low water levels when undercut banks and other bank habitats are unavailable, so the removal of LWD, including deadhead logs, could negatively affect the species. Minimum flows have been established in the drainage, but river water levels have declined an estimated 40% since human settlement, partly because of groundwater withdrawal outside the drainage, potentially imperiling this state Threatened species. [ABSTRACT FROM AUTHOR]

We studied the overwintering behavior of common musk turtles (Sternotherus odoratus) near the northern edge of the species' range using radiotelemetry. The turtles (n = 6) were found under the ice in winter in shallow (< 2 m) water, above sediments, in locales with abundant aquatic vegetation, and temperatures ranging between 0.4° and 1.7°C. American mink (Mustaela vison) appear to have killed 6 of the 9 radiotagged turtles, and 13 other common musk turtles in the same area during the winter, indicating that winter predation is an important source of mortality in this species. [ABSTRACT FROM AUTHOR]

The map turtles and sawbacks (Graptemys) sort by female head width into narrow-headed (microcephalic) females of 5 species that eat few mollusks, moderately broad-headed (mesocephalic) females of 4 species that eat moderately high amounts of mollusks, and broad-headed (megacephalic) females of 5 species that eat mollusks almost exclusively. The microcephalic species include a clade of 3 sawbacks, Graptemys nigrinoda, Graptemys flavimaculata, and Graptemys oculifera. The first 2 are sponge specialists, but 2 previous dietary studies of G. oculifera did not report sponges; both also lacked comparisons between the sexes. Both of the other sawbacks also feed on brackish-water mussels near the coast, but this phenomenon has not been examined for G. oculifera. Increased body sizes occur in coastal populations of both other sawbacks as well. We examined G. oculifera diets using fecal samples and found that contrary to the earlier results, they also fed primarily on sponges, as well as insects. Females also consumed algae, Asian clams, and, in a coastal population, mussels. In low-gradient river reaches near the coast, G. oculifera achieved large body sizes compared to populations inhabiting sandbar-dominated inland reaches; they were also large at the confluences of the Pearl River and a tributary creek with the Ross Barnett Reservoir. The fact that G. oculifera at the 2 confluences with a large inland reservoir showed the same trend in body size as they did at the coastal sites suggests that the primary reason for large body size may be thermal stability and/or slowing current that promotes biological production, rather than consumption of brackish-water mussels in coastal populations, as the mussels were absent near the reservoir. In addition, high predation by alligators may also occur at the reservoir confluence and coastal sites and select for large body sizes. Overall, the 3 allopatric sawbacks show a pattern of vicariant divergence as ecological analogues, consistent with findings for other allopatric sets of related species. [ABSTRACT FROM AUTHOR]

Most studies on wild ornate box turtles (Terrapene ornata) estimate maximum age in the 30s with some data suggesting that individuals may live beyond 50. We present data from a 29-yr study of 374 marked turtles in which at least 44% lived into their 30s and at least 3.5% survived into their 40s. Females may survive longer than males. Older turtles can affect reproductive potential of the population; therefore, conservation and management for this state-threatened species should account for longer lifespans than previously assumed. [ABSTRACT FROM AUTHOR]

The Central American river turtle (Dermatemys mawii) is one of the of the most critically endangered turtle species worldwide, as a result of habitat loss and heavy hunting for consumption. Research on D. mawii becomes more challenging as wild populations are disappearing, while basic ecological data are still required to inform conservation efforts. In this study, our aim was to analyze the diet of D. mawii based on sex, and compare the information provided by stomach flushing and fecal samples. We examined both types of samples from individuals captured in 2017 and 2018 in a lentic system in the Lacantun River Basin, Chiapas, Mexico. We identified 3 broad categories (aquatic macrophytes, riparian resources and invertebrates) and 12 different food items, of which four are new reports of vascular plants for the diet of this turtle. The principal items consumed by D. mawii were Pistia stratiotes (a free-floating macrophyte) and Ludwigia sp. (a riparian plant). A low index of relative importance (≤ 0.5) for invertebrates suggests that they may be ingested accidentally when feeding on plants. We did not detect significant sex differences in the relative contribution of food items between the two sampling methods; additionally, we found a large dietary overlap (Cλ ≥ 0.89) between sexes that indicates a similar use of resources in this lentic system. We found all 3 broad food categories in stomach flushing samples and only one (riparian resources) in fecal samples; however, we did not find significant differences in the number of food items. The use of both postingestion sampling methods provided a more comprehensive view of the diet of this herbivorous freshwater turtle. [ABSTRACT FROM AUTHOR]

With the exception of the savanna side-necked turtle (Podocnemis vogli) and the redheaded river turtle (Podocnemis erythrocephala), the species within the pleurodire genus Podocnemis have been relatively well-characterized in terms of their temperature-dependent sex determination (TSD) parameters. In this study, we incubated 4 nests of P. vogli (46 eggs) under controlled laboratory incubation conditions to determine whether this species also presents a TSD Ia pattern where males are produced at lower temperatures, characterize the constant temperature producing a 1:1 sex ratio (Tpiv), and document the transitional range of temperatures (TRT) that produces both sexes. The incubation temperatures employed were 29°, 31°, and 33°C (± 0.15°C). Our results were consistent with the conclusion that P. vogli exhibits a TSD Ia pattern, but it was not possible to document the Tpiv or the superior TRT, because the 29° and 31°C conditions produced all males and even the 33°C condition produced male-biased sex ratios, suggesting a high pivotal temperature for this species. We also documented maternal effects in initial size of the hatchlings, with the female that laid larger eggs producing hatchlings that were larger. Incubation periods of P. vogli were notably longer than those of its congeners incubated under comparable constant temperature and soil moisture conditions. In species of this genus, the TSD Ia pattern suggests that besides the threats these species face from overexploitation and habitat degradation, they also are highly vulnerable to the effects of global warming. [ABSTRACT FROM AUTHOR]

Eastern box turtles (Terrapene carolina) are becoming increasingly threatened by the rate of urbanization and habitat fragmentation. The high population density and heavy urbanization of Long Island, New York, provide an ideal system to examine possible drivers of differences in eastern box turtle shell damage and health in an urban landscape, as well as possible differences in sex and stage ratios. Over the course of our 2-yr study, we captured a total of 189 unique individual eastern box turtles across 20 sites on Long Island. Shell damage was evaluated according to a 5-level ranking system based on the amount and type of damage an individual turtle exhibited. To study eastern box turtle health, we calculated a body condition index using each turtle's body weight and straight-line carapace width. All damage and health data were compared by site, sex, and life stage using generalized linear models. These relationships were also analyzed against a set of land cover and land use variables. Across all comparative analyses performed, only the US Geological Survey land cover variable Dryland Cropland and Pasture showed a significant relationship to shell damage. Additionally, Long Island's eastern box turtles appear to exhibit greater rates of shell damage when compared with turtles in more rural parts of their range. We found male-biased sex ratios across the island; however, no definitive driver was identified. Our study underscores the need for future work on the long-term viability of eastern box turtle populations, specifically those inhabiting areas of high human population density. [ABSTRACT FROM AUTHOR]

Camera traps are very useful tools in determining the presence/absence of rare and cryptic species while shedding light on behavioral traits. Passive infrared triggered cameras are routinely used in homeothermic animals, but in ectothermic reptiles, this surveillance method has proven highly unreliable. As part of the conservation goal to provide better understanding and protection for the critically endangered freshwater turtle Batagur baska, we investigated their largely unknown nesting behavior and tested video-based motion detection by comparing 2 different camera-trapping systems and their settings under controlled conditions at the Vienna Zoo. A pixel-based video surveillance camera was superior to a camera trap with motion sensor. The surveillance camera allowed reliable motion detection at sensitive settings, and video capture precision could be enhanced by marking the terrapin with reflective tape. This video surveillance camera was then deployed over 2 breeding seasons (2019 and 2020) in the conservation breeding project of the northern river terrapin (B. baska, Gray 1830) in Bhawal National Park in Bangladesh. Analysis of video recording demonstrated for the first time that female northern river terrapins nested on average for a period of 1.5 hrs and produced a single clutch per year. Results indicate that females inspect sandbanks and visit suitable nesting sites several times before egg deposition, suggesting that nest-site selection is not random in B. baska. In addition, water temperature measurements of the breeding ponds in 2 captive breeding sites of the B. baska project showed an annual average temperature decrease to 168C–188C during the mating season and an average increase to 288C–318C before the nesting season. Temperatures on nesting nights vary between the 2 breeding sites and differ between nesting events within each site, suggesting that overall seasonal temperature shifts initiate the nesting periods, while other physiological and environmental factors might trigger the actual nesting event. With the help of consistent motion-triggered video recording, our study provides a first underpinning of the nesting ecology of B. baska. [ABSTRACT FROM AUTHOR]

The Hispaniolan slider, Trachemys decorata (Barbour & Carr 1940), is a freshwater turtle of conservation interest, endemic to the island of Hispaniola. The species is currently threatened by habitat destruction, hybridization with invasive species, and commercial harvest. However, the consumption of the Hispaniolan slider by human populations has received little attention. During the winter of 2017–2018, we conducted a survey to document the commercial use of freshwater turtles at Trou Caïman, one of the major wetlands in Haiti, based on interviews with 72 people representative of the local community. The strong demand for freshwater turtles from people living around the lake was related to classical uses such as meat consumption, artisanal jewelry, or the pet trade, but also to more-peculiar ones such as cleaning of hand-dug water wells, voodoo ritual, and folk medicine. Our results illustrate the importance of considering the socio-cultural context for designing efficient conservation plans for T. decorata in Haiti. We particularly discuss the pros and cons of developing turtle farming, possibly in conjunction with rice agriculture, as a potential solution to preserve the integrity and future of T. decorata. [ABSTRACT FROM AUTHOR]

In China, Hainan Island is a priority area for turtle conservation because of its biodiversity. Over the years, errors in turtle taxonomy and distribution have been made in the scientific literature, perpetuating into relevant laws and government documents and affecting conservation and management. In the present article, we describe the species of nonmarine turtles on Hainan Island, China, based on literature, museum specimens, and field surveys during the past 27 yrs. Historically, 23 nonmarine turtle species were recorded on Hainan Island. Among them, 9 species should be removed due to errors: 5 species are not naturally distributed on Hainan Island (Manouria impressa, Sacalia bealei, Cuora flavomarginata, Mauremys nigricans, and Mauremys reevesii), 3 are invalid hybrids (Ocadia philippeni, Sacalia pseudocellata, and Cuora serrata), and 1 is a synonym of another species (Mauremys megalocephala is a synonym of M. reevesii). In addition, of the 3 new species recorded from Hainan Island (Sacalia insulensis, Pelodiscus variegatus, and Pelodiscus parviformis), S. insulensis replaces Sacalia quadriocellata, P. variegatus is valid, and P. parviformis is likely an error. Therefore, there should be 12 nonmarine turtle species naturally found on Hainan Island: Platysternon megacephalum, Cuora galbinifrons, Cuora mouhotii, Cuora trifasciata, Geoemyda spengleri, Mauremys mutica, Mauremys sinensis, S. insulensis, Palea steindachneri, Pelochelys cantorii, Pelodiscus sinensis, and P. variegatus. Clarifying the presence and distribution of nonmarine turtle species will provide a reference for future research and practical guidance for conservation management on this turtle-rich island. [ABSTRACT FROM AUTHOR]

In general, chelonians are widely distributed, occupying areas with significant environmental variation, which may lead to great variations in their ecology such as morphological characteristics, sexual dimorphism, population structure, and reproductive aspects. In this context, our main objective was to characterize populations of Phrynops geoffroanus and Mesoclemmys tuberculata in areas of Caatinga and Atlantic Forest in Northeast Brazil to evaluate the relative importance of intraspecific factors and environmental differences in determining ecological parameters. Samples were collected in semiannual surveys (dry and rainy season) over a year. We measured morphometric variables and the mass of captured animals and correlated the reproductive pattern with the season and adults' reproductive condition. We did not find significant differences in size, maximum straight-line carapace length (SCL), or body mass of both species, regardless of sex, between the studied environments. We recorded reproductive males of both species throughout the year (dry and rainy seasons), and testicular volume was positively correlated with SCL. In contrast, eggs and oocytes were recorded exclusively in females collected during the rainy season. However, we found eggs and vitellogenic follicles simultaneously, indicative of multiple clutches in a reproductive season. In P. geoffroanus, we did not find a significant relationship between clutch size and female SCL, although egg volume was positively correlated with SCL. In M. tuberculata, we did not find a meaningful relationship between any of these parameters. Finally, the ecological parameters evaluated differed considerably between species and environments, presenting similar patterns in Caatinga and Atlantic Forest. [ABSTRACT FROM AUTHOR]

Infestation of Ornate Box Turtles (Terrapene ornata) by sarcophagid botflies was studied over 38 yrs in western Nebraska. At least 2% of captured individuals were infected, primarily in late spring following warm temperatures in the previous September. Botflies may be a significant cause of mortality in box turtles in some years. [ABSTRACT FROM AUTHOR]

The eruption of Mount Pinatubo in the Philippines in June 1991 reduced global temperatures over the following 2 yrs. The greatest suppression (apart from Antarctica) was centered in the northern Great Plains of North America, directly over my long-term turtle study site. Temperatures at that site in 1992 and 1993 were the coldest in at least 50 yrs. Normal annual hatchling recruitment of yellow mud turtles (Kinosternon flavescens) in the spring following incubation at that site averaged 375; however, only 3 hatchlings emerged in 1993 (1992 incubation cohort), and none emerged in 1994 (1993 incubation cohort). The depressed temperatures apparently prolonged incubation times to such an extent in 1992 and 1993 that hatching was nearly impossible before winter mortality. The result was a gap in the age class structure that was still evident 26 yrs later. This site is at the northern range limit of this species, and this event suggests that incubation temperatures (i.e., summer season length) may be responsible for that limit. [ABSTRACT FROM AUTHOR]

Box turtle (Terrapene spp.) reproduction has been relatively well studied in northern populations inhabiting more seasonal climates but is much less understood in the subtropics. We assessed female reproduction of T. bauri in southwestern Florida by quantifying courtship, mating, seasonal timing of nesting, clutch frequency, and clutch size. Box turtles were observed courting or mating in 10 out of 12 mo. Radiographs revealed oviducal eggs from January to August. To our knowledge, this is the earliest recorded detection of eggs in wild box turtles. Individual turtles produced 2–4 clutches of 1–5 eggs in a nesting season. This study provides further evidence that turtle populations at warmer climates exhibit extended reproductive seasons compared with similar populations in cooler climates. [ABSTRACT FROM AUTHOR]

The Rio Grande cooter (Pseudemys gorzugi) is an imperiled freshwater turtle native to the southwestern United States and northeastern Mexico. Previous studies investigating P. gorzugi diet have focused on the population occupying the Black River drainage in southeastern New Mexico, while Texas populations have remained unexamined. During the summer and fall of 2020, we studied the dietary habits of P. gorzugi and the syntopic red-eared slider (Trachemys scripta elegans) at San Felipe Creek, Texas, USA using fecal content and stable isotope analyses. We also compared the isotopic niches of these 2 co-occurring turtle species. Filamentous algae were, volumetrically, the most important food item for male, female, and juvenile P. gorzugi. Stable isotope mixing models indicated that lotic and lentic filamentous algae had the greatest proportional contribution to P. gorzugi and T. s. elegans diets, respectively. Stable isotope dietary mixing models also indicate T. s. elegans had a more carnivorous diet, composed mostly of red-rimmed melania (Melanoides tuberculata) and red swamp crayfish (Procambarus clarkii). Carnivory in this species was further supported by enriched δ15N values and higher trophic position estimates. Pseudemys gorzugi and T. s. elegans had δ13C and δ15N signatures that significantly differed, and the 2 species showed little overlap in isotopic niche space, suggesting a low likelihood of intense resource competition. Our results demonstrate that the diet of P. gorzugi, and the isotopic niche overlap between P. gorzugi and T. s. elegans at San Felipe Creek differ from that in the Black River drainage of New Mexico. The information provided here contributes toward a more complete understanding of P. gorzugi ecology, is useful for identifying suitable habitat worthy of conservation, and can help guide the development of feeding regimes for captive assurance colonies. La tortuga de Río Grande (Pseudemys gorzugi) es una tortuga de agua dulce en peligro nativa del suroeste de los Estados Unidos y el noreste de México. Estudios previos que han investigado la dieta de P. gorzugi se han enfocado en la población que ocupa el drenaje del Black River en el sureste de Nuevo México, sin embargo, las poblaciones de Texas no han sido examinadas. Durante el verano y el otoño de 2020, estudiamos los hábitos alimentarios de P. gorzugi y la tortuga de orejas rojas sintópica (Trachemys scripta elegans) en San Felipe Creek, Texas, EE. UU. mediante un análisis de contenidos fecales e isótopos estables. Incluso comparamos los nichos isotópicos de estas dos especies de tortugas en coexistencia. Las algas filamentosas fueron, volumétricamente, el alimento más importante para machos, hembras y juveniles de P. gorzugi. Los modelos de mezcla de isótopos estables indican que las algas filamentosas lóticas y lénticas contribuyen en mayor parte proporcionalmente a las dietas de P. gorzugi y T. s. elegans, respectivamente. Los modelos de mezcla dietética de isótopos estables también indican que T. s. elegans tiene una dieta más carnívora, compuesta en mayor parte de melania de borde rojo (Melanoides tuberculata) y cangrejo de río rojo (Procambarus clarkii). La característica carnívora en esta especie fue respaldada aún más por valores de δ15N enriquecidos y estimaciones de posición trófica más altas. Pseudemys gorzugi y T. s. elegans tuvieron valores de δ13C y δ15N que diferían significativamente y las dos especies mostraron poca superposición en el espacio del nicho isotópico, lo cual sugiere una baja probabilidad de competencia intensa por los recursos. Nuestros resultados demuestran que la dieta de P. gorzugi y la superposición del nicho isotópico entre P. gorzugi y T. s. elegans en San Felipe Creek difieren de aquellas del drenaje del Black River de Nuevo México. La información proporcionada aquí contribuye a un conocimiento más completo de la ecología de P. gorzugi, es útil para identificar un hábitat adecuado digno de conservación y puede ayudar a guiar el desarrollo de regímenes de alimentación para colonias de seguridad cautivas. [ABSTRACT FROM AUTHOR]

Testudines is a reptilian order characterized by low annual recruitment and delayed sexual maturity. One testudine species of conservation concern is the Rio Grande cooter (Pseudemys gorzugi), a taxon native to the southwestern United States and the westernmost species in this genus. A clear understanding of the reproductive biology of turtle species in the wild better informs conservation management options. The reproductive biology of P. gorzugi has been formerly investigated in the Black River of southeastern New Mexico. Because life history strategies of chelonian taxa may vary across geographic gradients, we examined the reproductive biology of this species at 3 sites in west Texas from 2017 to 2019. We detected follicle enlargement beginning in the fall with shelled eggs appearing as early as 7 April and as late as 12 August. We found a significant quadratic relationship between day of year and maximum follicle diameter (r2 = 0.22, F2,100 = 15.61; p < 0.05). A significant relationship between turtle size and clutch size was not detected nor was there a significant relationship between turtle size and egg width. We detected a record clutch size of 17 eggs and a mean ± SD clutch size of 11.4 ± 3.11. We observed a single instance of production of 2 clutches. The smallest gravid female we detected with shelled eggs had a plastron length of 179 mm. We also found that the probability of capturing a female gravid with shelled eggs was highest in early June. Our results suggest geographic variation occurs in the reproductive biology of P. gorzugi and highlight the importance of range-wide, temporally extensive sampling. Data presented herein can be included in population viability assessments and inform conservation recovery plans. Testudines es un orden de reptiles caracterizado por un bajo reclutamiento anual y una madurez sexual tardía. Una especie testudina de interés para la conservación es la tortuga del Río Grande (Pseudemys gorzugi), un taxón nativo del suroeste de los Estados Unidos y la especie más occidental de este género. Una comprensión clara de la biología reproductiva de las especies de tortugas en la naturaleza brinda mejor información a las opciones de manejo y conservación. La biología reproductiva de P. gorzugi se ha investigado anteriormente en el Río Negro del sureste de Nuevo México. Debido a que las estrategias de historia de vida de los taxones de quelonios pueden variar según los gradientes geográficos, examinamos la biología reproductiva de esta especie en tres sitios en el oeste de Texas entre el 2017 y 2019. Detectamos el agrandamiento del folículo a partir del otoño con la aparición de huevos sin cáscara desde el 7 de abril y tan tarde como el 12 de agosto. Encontramos una relación cuadrática significativa entre el día del año y el diámetro máximo del folículo (r2 = 0.22, F2,100 = 15.61; p < 0.05). No se detectó una relación significativa entre el tamaño de la tortuga y el tamaño de la nidada ni hubo una relación significativa entre el tamaño de la tortuga y el ancho del huevo. Detectamos un tamaño récord de nidada de 17 huevos y un tamaño medio ± DE de nidada de 11.4 ± 3.11. Observamos un solo caso de producción de dos nidadas. La hembra grávida más pequeña que detectamos con huevos sin cáscara tenía una longitud de plastrón de 179 mm. También encontramos que la probabilidad de capturar una hembra grávida con huevos sin cáscara era más alta a principios de junio. Nuestros resultados sugieren que se produce una variación geográfica en la biología reproductiva de P. gorzugi y resaltan la importancia del muestreo extenso temporal en todo el rango. Los datos presentados en este documento pueden incluirse en las evaluaciones de viabilidad de la población e informar los planes de recuperación y conservación. [ABSTRACT FROM AUTHOR]

The reproductive lifespans of turtles are consistently long, but reproductive cycles are under environmental control and thus can vary within species, populations, and individuals over time and space. Knowledge of turtle species' reproductive traits and their associated variances over time and space are critical to understanding the dynamics of turtle populations, especially those requiring management or conservation. Deirochelys reticularia is a species being considered for protection by the US Fish and Wildlife Service and contains 3 subspecies with some differences in reproductive characteristics of nesting season, annual nesting frequency, and egg retention. We collected ultrasound and x-radiograph data in Texas to identify the maturation size, nesting season, annual nesting frequency, and clutch size of female D. r. miaria in Texas. We observed no reproductive activity in individuals from 101 to 146 mm in plastron length (PL) and detected either unshelled eggs, shelled eggs, or both in individuals from 150 to 197 mm PL. Maturation sizes were similar to those in other regions and for other subspecies. We observed shelled clutches or nesting events from April to July, confirming a spring–summer nesting season in Texas consistent with other D. r. miaria sites and supporting the paradigm that the western subspecies does not follow the autumn–winter nesting season of the other subspecies. We found no evidence that individuals retain shelled eggs while aestivating or overwintering. Individuals nested up to 3 times/yr in Texas. Individuals laid 7–11 eggs and the mean clutch size was 9.2 eggs, similar to other regions and other subspecies. Nesting phenology is regionally variable, so management plans and policies for the species will need to consider that variation and potentially recognize management differences among D. reticularia subspecies. [ABSTRACT FROM AUTHOR]

Reeves' turtle (Mauremys reevesii) originated in China and was once one of the most widely distributed and abundant hard-shelled turtles in China; however, overharvesting has led to a sharp decline in its wild populations. A survey of Reeves' turtle was conducted from July 2021 to March 2022 in Qichun County, Hubei Province, China. A total of 74 individuals were caught in 26 ponds (1078 trap-days), indicating a catch effort population density of 0.07 individuals/trap-day. The 840 similar ponds in the field-surveyed towns indicate a population number of 2391 individuals and density of 4 individuals/km2. Our preliminary results suggest that Reeves' turtle populations face serious threats from human hunting activities, habitat destruction, and artificial release and urgently require an aggressive conservation program to ensure their survival. [ABSTRACT FROM AUTHOR]

Diamondback terrapins (Malaclemys terrapin) are a species of turtle that occupy coastal tidal marshes and nest on sandy areas above the high-tide line. Within the Grand Bay National Estuarine Research Reserve, Mississippi diamondback terrapin (M. t. pileata) shoreline nesting habitat at Grand Battures (also known as South Rigolets Island) has decreased from a 2.34-km length of surveyable shoreline in 2014 to a 1.45-km length of shoreline in 2021. Depredated nest surveys in 2021 detected the lowest number of nests to date at this location, with increased search effort, and this is likely due to the high rates of erosion described for this area. [ABSTRACT FROM AUTHOR]

In this study we describe some ecological features of Kinosternon scorpioides scorpioides from a section of the Argentina's Chaco ecoregion encompassing the provinces of Salta, Chaco, and Formosa, including the description of the capture sites and an analysis of the feeding ecology of the species. Six field trips were made during the spring and summer months from 2016 to 2020. We captured 23 turtles: 8 in Salta, 8 in Chaco, and 7 in Formosa; all corresponding to the dry portion of the Chaco ecoregion. They were found in a variety of aquatic environments (including those with considerable waste and human disturbance), and they also seemed to tolerate some fragmentation of the forest matrix. The analysis of 20 stomach contents and 14 fecal samples corroborated that K. s. scorpioides is predominantly an opportunistic omnivore, capable of feeding upon a diverse variety of invertebrates, some small vertebrates, and large volumes of vegetal material. The present study provides some baseline information about habitat requirements and feeding habits of the southernmost known populations of K. s. scorpioides. [ABSTRACT FROM AUTHOR]

We describe a new species of small chelid turtle from perennial streams in the Araguaia River subbasin near Serra das Andorinhas State Park, São Geraldo do Araguaia, Pará, Brazil. It is morphologically distinct and the smallest known member of the genus Mesoclemmys, with an average straight-line carapace length (CL) of 144 mm and maximum recorded CL of 170 mm. The species has a moderate head width of approximately 20% of CL. The carapace and dorsal soft parts are blackish, the plastron is light brownish yellow with a blackish brown central plastral figure, and the ventral soft parts are pale yellow. It has the largest femoral scutes of any Mesoclemmys and its plastral contact formula is Intergular > Anal > Humeral > Femoral > Abdominal > Pectoral > Gular. We describe the shell and skull morphology of the new species and performed genetic analysis using mitochondrial DNA (cytochrome c oxidase, subunits I [COI] and 16S) to build a phylogenetic tree for the genus, which placed the new species as sister to M. vanderhaegei. [ABSTRACT FROM AUTHOR]

For over 40 yrs we compiled egg length, egg width, and egg mass data for turtles in order to estimate the latter from published and unpublished data for the 2 former variables. The resulting data set includes nearly 18,000 eggs for 122 species and includes species-specific graphs (with linear regression equations and correlation coefficients) of egg width vs. egg mass and egg width vs. egg mass, as well as multiple regression equations of egg mass as a function of egg length and egg width (with statistical support). It is our hope that this note will stimulate authors to report egg mass data more rigorously, but also facilitate contemporary studies of reproductive strategies in turtles with more complete and accurate data. [ABSTRACT FROM AUTHOR]

Evolutionary theories predict major differences in life-history trait values of long- and short-lived organisms. Such comparisons have not been possible for chelonians because no short-lived turtle was known until research revealed that chicken turtles (Deirochelys reticularia; DR) have a maximum longevity of 21 yrs. Life-history trait values of DR females are 1) age at maturity of females = 5–6 yrs; 2) clutches per season = 1.6; 3) annual fecundity = 6–8 female eggs per female; 4) average juvenile survivorship from age 1 to maturity = 0.60; and 5) low average annual adult survivorship = 0.66. We compared DR with the very long-lived Blanding's turtles (Emydoidea blandingii; EB) in Michigan. Over 14 yrs with no mortality (the minimum age at maturity of EB), the maximum potential fecundity produced by a single female embryo and her mature female offspring was 5 female eggs for EB and 1040 eggs for DR. Comparisons of life table output for approximately stable populations of DR and EB resulted in cohort generation times of 7 and 37 yrs, respectively. The life-history prediction that short-lived organisms should produce smaller offspring was not supported. Average wet mass of eggs is 10 g (8.4–11.3 g) for DR and 12 g (10–14 g) for EB; and average wet mass of hatchlings is 7.3 g (6–9 g) for DR and 9.3 g (6–13 g) for EB. Both differences are smaller than expected based on the difference in longevity. Short-lived female DR have an unusual tactic of investing in high fecundity and making substantial body size-specific investment in large eggs, which may reflect why juvenile survivorship had greater influence on population change rates than did adult survivorship. In contrast, adult survivorship had the greatest influence on population change rates of EB. Comparison of cohorts of 1000 female DR and EB hatchlings highlights the differences in life histories of short- and long-lived turtles: all DR would be dead by the time the last female EB had reached maturity at 21 yrs of age. [ABSTRACT FROM AUTHOR]

The alligator snapping turtle (Macrochelys temminckii) has been proposed as a Threatened species under the US Endangered Species Act and is considered Vulnerable by the International Union for the Conservation of Nature. To provide additional markers for conservation genetic studies, we identified 60 potential microsatellite loci, with 38 being polymorphic in M. temminckii, as well as successful cross-amplification of 12 and 32 polymorphic loci in the Suwannee alligator snapping turtle (M. suwanniensis) and Eastern snapping turtle (Chelydra serpentina), respectively. These loci will be useful in genetic studies associated with informing future management decisions for M. temminckii and the other species of Chelydridae. [ABSTRACT FROM AUTHOR]

The Khorat snail-eating turtle (Malayemys khoratensis) is a recently described (2016), poorly studied freshwater turtle known from the Khorat Plateau in Thailand and a small area near Vientiane, Lao People's Democratic Republic. We investigated the occurrence and natural history of M. khoratensis during field surveys of Xe Champhone Ramsar Site (XCRS) and Nong Louang Wetland Complex (NLWC) in Savannakhet Province, and also examined museum specimens and published and unpublished photographs of Malayemys spp. from Lao. Our field surveys confirmed the occurrence of M. khoratensis in the XCRS and NLWC, where populations remain subject to harvest at levels unlikely to be sustainable. We examined 7 museum specimens from Vientiane, Savannakhet, Khammouan, and Champasak provinces. Museum specimens from Vientiane, Savannakhet, and Khammouan provinces were referable to M. khoratensis. Published photographs confirm the occurrence of M. khoratensis in Vientiane Province, and Malayemys subtrijuga in Champasak Province. Collectively, our records extend the geographic distribution of K. khoratensis by > 300 km from previously reported localities. We posit the existence of a biogeographic barrier in southern Lao and adjacent Thailand that separates the allopatrically occurring M. khoratensis and M. subtrijuga. [ABSTRACT FROM AUTHOR]

In 2015, nearly 4000 critically endangered Palawan forest turtles (Siebenrockiella leytensis) were confiscated on their native island of Palawan in the Philippines after being illegally harvested for the international wildlife trade. Local conservation biologists and an international team of veterinary and husbandry personnel evaluated, treated, and repatriated the majority of turtles (88%) over a 3-mo period. Common pathologic findings included ophthalmic, dermatologic, musculoskeletal, and gastrointestinal lesions, including keratitis, osteomyelitis of the shell and digits, pododermatitis, and colonic nematodiasis. Hemogram results indicated severe leukocytosis in many individuals. Specimens for genetic analysis and molecular diagnostics were archived, and several intact carcasses were established as museum specimens. International collaboration may be required to ensure the confiscation and survival of illegally traded endangered wildlife, with ongoing efforts toward enhancing the law enforcement, husbandry, and veterinary capacity of range country personnel. [ABSTRACT FROM AUTHOR]

Although commercial hook and line fisheries pose a well-documented and significant threat to worldwide sea turtle populations, recreational hook and line fisheries remain understudied. This article describes information from sea turtle bycatch reported from interactions in the recreational hook and line fishery, as well as survey results from recreational anglers in Virginia from 2014 through 2018. Reports of interactions increased annually during the study with Kemp's ridley sea turtles (Lepidochelys kempii) reported most frequently (n = 162), followed by 45 loggerheads (Caretta caretta), 6 green turtles (Chelonia mydas), and 39 unidentified sea turtles. Commonly encountered bait types were similar between surveyed anglers and bait used during turtle interactions, with significantly more squid bait noted during turtle interactions (51%) than used by surveyed anglers (29%) (χ2 = 41.32, p < 0.0001). Additionally, bloodworms and artificial bait were encountered comparatively less frequently during turtle interactions. Overall, interactions with the hook and line recreational fishery in Virginia appear opportunistic and involve otherwise healthy animals, presenting limited means for mitigating sea turtle bycatch. In the absence of regulatory oversight of bycaught sea turtles in the recreational fishery, mitigating injury from these interactions through targeted outreach provides a short-term solution to reducing the severity of these inevitable interactions. [ABSTRACT FROM AUTHOR]

Dermatemys mawii is a critically endangered freshwater turtle endemic to Central America. In the wild, these turtles are thought to be wholly herbivorous as adults and feed on a variety of vegetation; however, no studies have quantitatively assessed potential dietary differences based on biotic and abiotic factors. The purpose of our study was to describe and quantify the wild diet of D. mawii and assess differences based on habitat, maturity, and sex. We evaluated the stomach contents of 66 turtles legally harvested by local hunters for personal consumption throughout the country of Belize. Percent volume (by displacement) and percent frequency of each stomach item were used to calculate an index of relative importance (IRI). One algal and 6 plant families contributed to an overall diet composition consisting of leaves, flowers, stems, seedpods, seeds, and fruit. Rocks and invertebrates were also consumed, although we believe these to be incidental consumption. The leaves of the riparian tree Inga edulis were present in 73.1% of turtle stomachs and accounted for almost half of the total volume of all stomach contents combined. We used Spearman rank correlation coefficients to test the null hypothesis that there was no correlation in the rankings of stomach items (i.e., there were differences) when comparing turtles by habitat, age, and sex. There were significant differences in the ranking of food items between river and lagoon habitats, with lagoon turtles relying heavily on the algae Nitella sp.; however, the stomach contents from both habitats were equally diverse (Hrivers = 1.68, Hlagoons = 1.64). There were no differences in IRIs between adults and juveniles or between males and females. Our results emphasize the importance of habitat in D. mawii diet selection and the importance of leaves from riparian plants species that are shed into their aquatic habitats. [ABSTRACT FROM AUTHOR]

Invasive red foxes (Vulpes vulpes) are a serious conservation issue for Australia's freshwater turtle species, including the endangered Bell's turtle (Myuchelys bellii). As many as 96% of Australian freshwater turtle nests may be depredated in a season by foxes. Current methods of turtle nest protection rely on early detection of nesting activity, followed by nest-specific structures to prevent predation. An alternative method to provide protection against fox raiding was tested: nesting refuge structures based on a design successfully used in the United States to protect diamondback terrapin (Malaclemys terrapin) nests. Six wood and chicken wire structures were placed at different sites beside large riverine pools on the Macdonald and Gwydir rivers, northeastern New South Wales, Australia, in the summers of 2019–2020 and 2020–2021. Sites were chosen for known previous nesting activity or presence of mature females, and each structure was placed in typical Bell's turtle nesting habitat at known nesting sites. Prior to placement, the soil was tilled with a rotary hoe to make the interior of the structure more enticing as nesting habitat, because Bell's turtles had been previously seen to nest in disturbed soils. Although females did approach the structures and in one case entered, no females were recorded nesting inside. Further, severe flooding in both years damaged and/or displaced 4 of the 6 structures. Rigid nest protection structures were therefore not shown to be an effective nest protection method for this species, despite their success in other regions for other species. Negative results such as these are important for conservation studies because they guide conservation efforts away from expending limited resources on ineffective methods and strategies. [ABSTRACT FROM AUTHOR]

Freshwater megafauna populations, which are declining worldwide, are well known but often overlooked and understudied compared with marine and terrestrial megafauna. One species of freshwater megafauna is the Suwannee alligator snapping turtle (Macrochelys suwanniensis), which is endemic to the Suwannee River drainage in Georgia and Florida. Several trapping studies have examined M. suwanniensis distribution, body size, and population structure, but little information exists regarding its population status. The objectives of our study were to 1) estimate population size, 2) estimate apparent survival, and 3) model population growth rates (k) by conducting a capture–mark–recapture study of M. suwanniensis in the Suwannee River in Florida. From 2011 to 2013, we repeatedly sampled 12 randomly selected 5-km sites along the Suwannee River for M. suwanniensis using baited hoop-net traps. We captured 126 individuals and had 29 recaptures. Both adult males and adult females had very high apparent survival (0.99), whereas juveniles had lower apparent survival (0.32). We estimated a population density of 6.6 turtles/river km, indicating a population of 1709 (95% CI, 1205–2694) M. suwanniensis from the town of White Springs to the upper limit of the estuary in the main stem of the Suwannee River (approximately 259 river km). We constructed 2 postbreeding census matrix population models for M. suwanniensis and incorporated parameters from this study and from the literature. Both matrix population models suggested a slightly decreasing population (k = 0.99), but because of the uncertainty around our estimates, we consider the population trend to be unclear. Elasticity analysis revealed that k was most sensitive to changes in adult survival compared with other model components. This is a conservation concern because adult M. suwanniensis may be incidentally killed by fishing gear. Our study was short-term, and our analyses had limitations; therefore, we recommend future areas of research, including long-term population monitoring. [ABSTRACT FROM AUTHOR]

The alligator snapping turtle (Macrochelys temminckii) has been proposed as a Threatened species under the US Endangered Species Act and is considered Vulnerable by the International Union for the Conservation of Nature. To provide additional markers for conservation genetic studies, we identified 60 potential microsatellite loci, with 38 being polymorphic in M. temminckii, as well as successful cross-amplification of 12 and 32 polymorphic loci in the Suwannee alligator snapping turtle (M. suwanniensis) and Eastern snapping turtle (Chelydra serpentina), respectively. These loci will be useful in genetic studies associated with informing future management decisions for M. temminckii and the other species of Chelydridae. [ABSTRACT FROM AUTHOR]

Eiselt's pond turtle (Emys orbicularis eiselti) was described in 1998, based on only 4 museum specimens collected in the 1960s and 1970s. Its distribution range has been massively reduced by large-scale drainage measures and only little suitable habitat remains near the Turkish–Syrian border. During 20-yr-long fieldwork we could locate only 18 individuals of this subspecies. We estimate the number of surviving Eiselt's pond turtles to be less than 100 mature individuals in the wild. The distribution range (area of occupancy) in the Amik Maraş Rift Valley shrank from originally 11,612 km2 to only 206 km2 at present (approx. 2%), qualifying E. o. eiselti as a Critically Endangered taxon. Without immediate conservation measures and the strict protection of the remaining habitat, the subspecies will soon be extinct. [ABSTRACT FROM AUTHOR]

We describe a new extant species of freshwater turtle from Brazil: Mesoclemmys sp. nov., a medium-sized toad-headed turtle (mean carapace length = 189.5 ± 25.8 mm), which to date has only been found in the Brazilian Amazon Basin, western Pará State, Central Amazon, and the lower Amazonas River Basin. It is easily distinguished from its sympatric congeners by differences in body size, head size, carapace shape, and coloration. The head is triangular and completely black, with large red eyes positioned anteriorly and a pair of long, light yellow barbels positioned anteriorly close the mandible. The carapace is oval and colored dark reddish brown. The plastron is black in the central region and burnt-yellow along the edges and ventral aspects of the marginal scutes and bridge, with dark seams. The plastral formula is 3-5-7-4-1-6-2. The new species inhabits temporary rainwater ponds under closed-canopy rainforest and has a known geographic range of 2183 km2. Sequences of fragment mitochondrial DNA (cytochrome c oxidase subunit I and 16S) of the new species were determined and compared with the available GenBank sequences. Our phylogenetic results indicate that the specimens represent a divergent taxon within Mesoclemmys and a robust analysis of morphological data corroborates the existence of a new distinct species of Mesoclemmys, described herein. [ABSTRACT FROM AUTHOR]

We present 4 observations of hawksbill turtles Eretmochelys imbricata found in anchialine ponds on 3 islands in The Bahamas. These ponds had no surface connection to the ocean, but they were connected by subterranean conduits that, in at least one instance, extended over 1.5 km in length. It is possible that the turtles were placed in these ponds by humans; however, it appears more likely that they accessed these habitats via the subterranean conduits suggesting that anchialine ponds may function as either novel habitat or a potential ecological trap. [ABSTRACT FROM AUTHOR]

Knowledge of the spatial ecology of many turtle species is lacking or limited by small sample sizes of study animals, short study periods, or incomplete representation of the species' geographic range, all of which can present barriers to science-based management and conservation. The wood turtle (Glyptemys insculpta) is a declining North American freshwater turtle that is now listed as threatened or endangered in several US states and Canadian provinces. Local-scale knowledge of wood turtle movement patterns and home range sizes is needed for more effective management and regulatory protection, yet the spatial ecology of this species remains undescribed in large portions of its range. We radiotracked 31 wood turtles for 1–5 yrs each in a stream system along the border of New York and Connecticut to describe their movement behavior and inform management efforts in this previously unstudied region. Annual and multiyear 95% minimum convex polygon home range sizes averaged 2.8 (± 3.79 SD) ha and 5.2 (± 7.36 SD) ha, respectively. Males had significantly larger annual and multiyear home ranges than did females, often by severalfold. Overlap of home ranges from one year to the next ranged from 10.5% to 99.7% and averaged 62.6% (± 22.86% SD). Home range centroids shifted 3.8–328.1 m (x̄ = 70.3 ± 80.31 m SD) from year to year and averaged 41.2 m (± 40.56 m SD) from the stream and 138.4 m (± 70.66 m SD) from the nearest road across all individuals. Most turtles' home ranges spanned one or both of the major roads in our study area, illuminating the threat of vehicle collision mortality to the viability of this population. Hibernaculum fidelity was low, with only 15% of turtles hibernating in the same location as in the previous year. Our results suggest that management efforts for wood turtles in western Connecticut and the adjacent region of New York should consider that males (the wider-ranging sex) use an average of 5.3 ha to meet their resource requirements over the course of one annual cycle, buffers of at least 116 m surrounding streams should be protected, habitats that are distant from roads should be prioritized for conservation, and measures that facilitate safe passage beneath roads should be implemented whenever roads are present near occupied wood turtle habitat. [ABSTRACT FROM AUTHOR]

The Suwannee alligator snapping turtle (Macrochelys suwanniensis) was first described in 2014. The species is thought to occur in blackwater and spring-fed streams of sufficient size throughout the Suwannee River drainage, but we have limited detailed information regarding its range. To clarify the distribution of M. suwanniensis, we compiled 111 museum, 16 literature, and 40 other credible records and trapped streams throughout the Suwannee drainage in Georgia and Florida, plus 8 streams in the Big Bend region of Florida (total of 1893 trap nights). We documented the first records from the Willacoochee River and Okapilco, Piscola, Warrior, Jones, and Toms creeks in Georgia and from Rocky and Olustee creeks in Florida. Relative abundance based on catch per unit effort (CPUE) varied among streams (0.00–0.50) and sections of the same stream. Macrochelys suwanniensis is apparently scarce in the Okefenokee Swamp and in the Suwannee River upstream of White Springs, Florida (none trapped), but it occurs in small blackwater tributaries in this section of the river in both states. In the Suwannee River between White Springs and the estuary, we had a mean CPUE of 0.25, and the highest trapping success in Florida was in downstream reaches of the Suwannee River and in its major tributaries, the Santa Fe and New rivers. The species is widely distributed in Georgia, but relative abundance in most streams appears lower than in Florida. In Georgia, we had the highest trapping success in the Alapaha drainage and in sections of the Little River and Okapilco Creek in the Withlacoochee drainage. In Florida, we failed to trap Macrochelys in the purported distribution gap between the Suwannee and Ochlockonee drainages and in the Wacasassa River to the south, indicating that this species is restricted to the Suwannee drainage. [ABSTRACT FROM AUTHOR]

We examined the prevalence (% of turtles examined) of leeches (Placobdella parasitica) and algae (likely Arnoldiella sp.) on Chrysemys picta found in 4 recently created ponds in central Ohio. Chrysemys picta in ponds with fish were less likely to have leeches and more likely to have algae than those in ponds without fish. Across all ponds, males and females did not differ in leech or algal prevalence, whereas adults were more likely to have leeches than juveniles, but did not differ in algal prevalence. [ABSTRACT FROM AUTHOR]

The goal of this study was to determine whether marine turtle (loggerhead) embryos communicate with one another using mechanical cues detected through the flexible egg shell. In the process, the embryos might develop faster and hatch with greater synchrony (as occurs in some freshwater turtles). To find out, we performed experiments under controlled laboratory conditions to determine how changes in the embryonic social environment affected both the rate of development and the temporal pattern of hatching when temperature, moisture, and substrate composition were controlled. We found that developmental periods were significantly shortened and hatching synchrony was increased when 1) a critical number of eggs were in contact with one another, facilitating the possibilities for embryos to communicate, and when 2) a threshold number of those eggs remained viable and completed development at about the same time. We used this information, in combination with field studies done by others, to clarify temporal relationships between hatching and emergence from the nest that occurs several days later. [ABSTRACT FROM AUTHOR]

The nesting activity of the Chinese softshell turtle (Pelodiscus sinensis) in its natural habitat is largely undocumented despite its broad geographical distribution across East Asia. Here, we report on female nesting behaviors, egg incubation, and hatchling emergence of P. sinensis on the Yellow River in northwestern China. In this region, the turtle is currently threatened by overharvesting, and successful conservation strategies should include strict monitoring of hunting and trade activities. [ABSTRACT FROM AUTHOR]

Wood turtles (Glyptemys insculpta) are considered rare or threatened throughout their range. Populations in Iowa occur at the western periphery of the species' range and may be particularly vulnerable to extirpation due to low population density, geographic isolation with restricted opportunities for gene flow, a small range, and a high percentage of land that has been converted for agriculture. To improve our understanding of the ecological needs of the species and to provide targeted conservation of required habitat, determining home range size, site fidelity, and movement patterns is needed. We conducted a 2-yr radiotelemetry study on wood turtles in Iowa to provide baseline data on movement patterns (including estimated total distance moved in an active season and mean daily movement) and home range size and site fidelity between years of survey. Home range size of adult male and female wood turtles differed significantly for 100%, 95%, and 50% minimum convex polygon home range, with male mean home range being nearly 3 times the mean size of female home range. Stream home range length also differed significantly between males and females, with males utilizing a larger portion of lotic habitat. Both sexes showed a high degree of site fidelity to annual home ranges but not to specific overwintering locations. Our study provides important data on home range size, degree of site fidelity, and movement patterns of wood turtles from an isolated population in Iowa at the southwest periphery of the species' range. These data will inform conservation agencies on relevant habitat protection and management strategies of riparian areas that are necessary for the continued survival and protection of the species in the state. [ABSTRACT FROM AUTHOR]

Management decisions for species are often based on estimates of abundance, which can be difficult to obtain for species that are a challenge to survey, as are some reptiles. Information on abundance and population status are lacking for the diamondback terrapin (Malaclemys terrapin), a coastal species that inhabits brackish waters and plays an important trophic role in the saltmarsh ecosystem. Population declines are suspected throughout the species' range, and its population status is unknown in Florida. Of the 5 subspecies that inhabit Florida's coastline, the most understudied subspecies may be the ornate diamondback terrapin (M. t. macrospilota). We conducted a capture–mark–recapture study of M. t. macrospilota during the summer of 2013 on 3 adjacent coastal islands in the eastern panhandle of Florida that provided information on population size and demography. We captured 334 individuals; modeling estimated a population size of 1282 (867–1905 95% CI) and a density of 150 terrapins/ha. Population size decreased throughout the study, suggesting that this population is an aggregation that seasonally emigrates from the islands. This emigration trend was more evident for females. Males outnumbered females 4:1, and females were larger than males. Our study is the first to report on M. t. macrospilota populations in the Florida panhandle. We recommend collaborative, long-term population monitoring at our sites to estimate population trends that will be crucial for managing this subspecies. [ABSTRACT FROM AUTHOR]