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.

Social behaviors represent a central tenet of ecology and evolutionary biology, but remain widely undocumented in reptiles. Although marine turtles have been studied for decades, the prevalence, importance, and potential role of social behaviors have been largely overlooked. Consequently, marine turtles have predominantly been characterized as nonsocial animals in the literature. Here we report on visual observations of hawksbill turtles (Eretmochelys imbricata) inhabiting a nearshore coral reef in Hawai‘i that reveal a complex array of social behaviors. Combined with recent evidence for social behaviors in other marine turtle species, our results confirm that traditional views of nonsocial life histories are incomplete and that social behaviors are likely prevalent in many marine turtle species. Our findings have important implications for marine turtle management and suggest increased research into social behaviors is warranted across the taxon.

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.

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.

The Florida box turtle (Terrapene bauri) population on Egmont Key National Wildlife Refuge, Florida, was the subject of long-term ecological studies from 1991 to 2006. The Egmont Key population was relatively large and stable compared with other populations of Terrapene spp. that were studied for multiple decades, with an increasing population trend and approximately 1500 turtles in 2002. We conducted a reassessment of the population in 2017–2018, and we specifically evaluated the effects of a 26.1-ha wildfire that occurred in July 2016. In March 2017 we implemented randomized, time-constrained surveys, which detected an average of 38.5 dead box turtles per ha, from which we extrapolate approximately 1005 (95% CI = 786–1223) detectable, dead box turtles across the extent of the 2016 wildfire. Of 259 dead box turtles found during this survey, a minimum of 65 were judged to have died coincident with the 2016 wildfire. Another 43 turtles, apparently killed by predators (most likely raccoons, Procyon lotor), were found in burned and unburned areas. One hundred forty-eight were too badly burned or deteriorated to estimate the likely cause of death. Additional surveys in 2017 and 2018 further assessed the condition of the remaining box turtle population. Between March 2017 and March 2018 we detected a total of 347 box turtles, of which 32 were alive and 315 were dead. We estimated the population to consist of 65.5 (95% CI = 41.6–149.1) live turtles, indicative of a > 95% population decline since the early 2000s. Our results illustrate the need for populations of nonlisted, yet vulnerable, species to be prioritized on protected sites, and monitored to detect the effects of stochastic, chronic, and synergistic sources of mortality.

Five species of sea turtle—the green (Chelonia mydas), hawksbill (Eretmochelys imbricata), leatherback (Dermochelys coriacea), loggerhead (Caretta caretta), and olive ridley (Lepidochelys olivacea)—feed in the coastal waters of India, nest on the mainland and island beaches, and are an important component of India's natural and sociocultural heritage. Sea turtles spend most of their life cycle at sea, so structured studies of the biology of nonnesting populations are challenging. However, fishers' ecological knowledge (FEK) could indicate sea turtle distribution, abundance, and population trends. Structured interviews with 93 male fishers at Sagareshwar Beach, Vengurla, in the Sindhudurg District of Maharashtra revealed observations of all 5 sea turtle species in local waters. Importantly, this was the first known record of loggerhead turtles for the Sindhudurg District of the state coastline and added to infrequent records of leatherback turtles over the previous 20 yrs. Observations were more common at a time when adult turtles are likely to be courting and mating, although this behavior was not observed. Fishers did not contribute ecological knowledge about sea turtle distribution from the waters they fished, potentially because of the method used to collect information on maps or reluctance to indicate areas fished. Estimates of abundance were widely disparate, but perceived decreases in the size of local populations were common among respondents. Outcomes of our study suggest that the FEK of small-scale coastal fishers operating in even a small area is of value in identifying potential areas for focused investigations on in-water populations of sea turtles.

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.

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.

To conserve or restore riverine turtles, managers need baseline information on subpopulation structure and abundance in multiple rivers across large geographic areas. Assessing the demographics and morphological characteristics of different subpopulations can increase our understanding of how anthropogenic factors influence mortality and reproduction. We examined spiny softshell turtles (Apalone spinifera) in 5 rivers at the western edge of the species' range in southcentral Montana, where no commercial harvest is allowed. Over 4 yrs, we captured 637 spiny softshell turtles with fish-baited hoop traps. Our objective was to compare the subpopulation demographics in the Yellowstone River—considered one of the most intact rivers in the conterminous United States—to 3 Yellowstone River tributaries (Bighorn and Clarks Fork rivers and Pryor Creek) and the adjacent Musselshell River. Subpopulations differed significantly based on the demographic metrics we examined (e.g., mean sizes and sex ratios), and we documented limited numbers of males (4%–15%). Reproductive potential and mortality of adults among rivers appeared distinct based on juvenile and size class distribution of length-frequency histograms. This information from unharvested populations illustrates the variability in subpopulation demographics of riverine turtles.

Vegetation has been shown to influence nest environment (temperature, humidity), affecting hatchling's development as well as emergence success, and has also been used as a cue during the selection of a nesting site. For green turtles, Chelonia mydas, nest density is typically higher in the vegetated zones. This study evaluated the influence of vegetation presence and percent cover on the nesting success and embryonic development of green turtles in Guanahacabibes Peninsula, Cuba. The vegetation cover had a positive and significant relationship with the number of nests (r = 0.56, p = 0.01, n = 17). Two vegetation patches are identified with different vegetation cover values: 29% for the first (closer to the high tide line) and 37% for the second. We found the highest nesting success (70%) and nest relative frequency (15% of total nesting) around the first patch of vegetation. Median hatchling emergence success was 88% (40%–96%, n = 54) in the first patch and 93% (78%–100%, n = 40) in the second. The incubation period was lower in the first patch (mean = 51 d, range = 48–60 d, n = 44) and higher in the second (mean = 54 d, range = 45–67 d, n = 39). This is the first study that reveals the positive impact of sandy coast vegetation on Guanahacabibes' green turtle nesting and will be useful in conservation actions such as native vegetation restoration plans and temperature control using shade management with vegetation.

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.

The recovery of depleted sea turtle populations will require careful documentation of sea turtle reproduction sites and anthropogenic mortality risks throughout their known ranges. Although sea turtle nesting is well documented in many locations, there remains a paucity of data on the species and nesting ecology in western Africa. Here we provide the first longitudinal study of sea turtle nesting activity in Ghana. In decreasing order of abundance, we observed nesting olive ridley (Lepidochelys olivacea) (60 nests/yr), leatherback (Dermochelys coriacea) (17 nests/yr), and green (Chelonia mydas) sea turtles (2 nests/yr) along 3.7 km of beach. The primary nesting season for all species is September through January; however, olive ridley turtles sporadically nest throughout the year. Olive ridley nesting activity significantly declined during the study period (R² = 0.53, p = 0.04). The primary risk factors for these animals are fishery bycatch, direct harvest of nesting females, and egg poaching.

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.

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.

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.

Skin biopsies are routinely collected from sea turtles for a variety of molecular analyses; however, almost no information exists on the natural healing rates at the site of the biopsy. Here, we monitored the healing rates of 17 juvenile green turtles (Chelonia mydas) for up to 488 d after we took a 6-mm biopsy tissue sample in Eleuthera, The Bahamas. Although scarring persisted for several months, biopsy sampling had a minimal long-term impact—tissue repair and maturation was observed after a year and a half, and there was no evidence of infection at any point during the healing process.

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.