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Critically Endangered and Endangered (CRþEN), Threatened (CRþENþVU), and Listed species of turtles and tortoises as percentages of the total number of recognized species at the time, as published on IUCN Red Lists 1982-2018 and on this TFTSG Red List 2018. Data sources as in Table 1. (Color version is available online.)
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We present a review and analysis of the conservation status and International Union for Conservation of Nature (IUCN) threat categories of all 360 currently recognized species of extant and recently extinct turtles and tortoises (Order Testudines). Our analysis is based on the 2018 IUCN Red List status of 251 listed species, augmented by provisiona...
Contexts in source publication
Context 1
... lower percentages of Threat- ened species is that, of the species previously not included on the IUCN Red List, a lower percentage have now been provisionally assessed by the TFTSG as Threatened and many are DD or LC. However, when we calculate these figures as percentages of all turtle species recognized at the time of the assessments (Table 1; Fig. 2), they are now markedly higher than in previously published IUCN Red Lists, and we see that the percentages of both CRþEN and Threatened turtles and tortoises have actually increased over the ...
Context 2
... lower percentages of Threat- ened species is that, of the species previously not included on the IUCN Red List, a lower percentage have now been provisionally assessed by the TFTSG as Threatened and many are DD or LC. However, when we calculate these figures as percentages of all turtle species recognized at the time of the assessments (Table 1; Fig. 2), they are now markedly higher than in previously published IUCN Red Lists, and we see that the percentages of both CRþEN and Threatened turtles and tortoises have actually increased over the ...
Context 3
... lower percentages of Threat- ened species is that, of the species previously not included on the IUCN Red List, a lower percentage have now been provisionally assessed by the TFTSG as Threatened and many are DD or LC. However, when we calculate these figures as percentages of all turtle species recognized at the time of the assessments (Table 1; Fig. 2), they are now markedly higher than in previously published IUCN Red Lists, and we see that the percentages of both CRþEN and Threatened turtles and tortoises have actually increased over the ...
Similar publications
Organisms display a considerable variety of body sizes and shapes, and macroevolutionary investigations help to understand the evolutionary dynamics behind such variations. Turtles (Testudinata) show great body size disparity, especially when their rich fossil record is accounted for. We explored body size evolution in turtles, testing which factor...
Citations
... Globally, freshwater turtles are threatened with extinction (Rhodin et al. 2018;Stanford et al. 2020) and understanding the effects of changes in habitat quality on populations is of paramount importance to conservation. Deterioration of water quality, such as increases in salinity or decreases in oxygen concentration, have led to changes in freshwater turtle behaviour, health, and even declines in populations (Kinneary 1993;Clark et al. 2009;Bower et al. 2012). ...
Climate change and human activity are changing the characteristics of freshwater systems all over the world. Water quality is an important environmental variable to turtles, and many species have limited tolerances to different abiotic parameters. Despite the potential for extreme effects of water quality variables on turtle physiology and behaviour, we still do not understand the extent to which many species identify and select different water quality parameters within their habitats. The eastern long‐necked turtle ( Chelodina longicollis ) resides in both natural and highly degraded systems throughout south‐eastern Australia. However, their ability to perceive the quality of these environments and whether they select a habitat based on specific water quality attributes is unknown. Our objective was to identify the preferences of eastern long‐necked turtles to different water quality parameters. We quantified the time spent in varying concentrations of five abiotic variables: dissolved oxygen, fertiliser, pH, salinity, and turbidity. Testing arenas consisted of four tubs, each with a different concentration of a selected water quality variable, and turtles were allowed to choose in which concentration they spent their time. This was replicated for each of the five variables, using a sample size of 10 turtles. Eastern long‐necked turtles strongly preferred the freshwater control treatment over treatments with high salinity. They did not show strong preferences towards treatments with different dissolved oxygen, turbidity, and fertiliser or pH. We show that although C. longicollis occupies a variety of natural and man‐made water bodies, they do prefer specific salt concentrations, which may influence their subsequent habitat selection within their range. Our trial model may also reveal stronger habitat preferences of more sensitive turtle species, which may be increasingly vulnerable to changes in their natural habitats.
... Considering the concerning conservation status of many turtles (Rhodin et al., 2018;Stanford et al., 2020), it is critical to understand their movement ecology to better understand their ecological needs. This study documents the movements of 24 P. peninsularis and 24 P. nelsoni over 52 weeks (August 2018-July 2019) within the Wekiwa Springs, Rock Springs, and Wekiva River drainage to gain a better understanding of how these populations use this large, protected habitat. ...
Despite their ubiquity in many freshwater habitats, little is known about the spatial and movement ecology of Cooter turtles (Pseudemys). We captured and tracked 24 Florida Red-bellied Cooters (P. nelsoni) and 24 Peninsula Cooters (P. peninsularis), 12 of each sex, in the protected spring-fed Wekiva River, Wekiwa Springs, and Rock Springs system. Most cooters stayed in the same spring or river section (n = 30). We hypothesized and found ~25% of Peninsula Cooters preferred slower moving water in the Wekiva River, while > 90% Florida Red-bellied Cooters preferred faster moving spring boils or runs. We hypothesized females would have larger ranges than males but using 1,061 movements summarized with ten movement metrics, we observed few differences between species or sexes. Instead, the high variability between individuals clustered into two movement modes—20 turtles that were relocated in the same vicinity (typically < 500 m) and 27 turtles that moved throughout the spring system. We attribute the lack of differences between sexes and species to the optimality of spring systems for herbivorous turtles with constant water temperature, dense macrophytes, and abundant basking spots. Our study highlights the need for continued protection of spring systems to conserve these refuges of Pseudemys abundance in increasingly altered hydroscapes.
... Amphibians are among the most threatened vertebrate groups globally (Rhodin et al. 2018). In comparison, despite evidence indicating an ongoing global decline of reptiles (Huey et al. 2010, Tingley et al. 2016, conservation of the group is comparatively neglected (Geyle et al. 2020). ...
Habitat loss and fragmentation is the greatest threat to global biodiversity and is especially acute in biodiversity hotspots such as the Atlantic Forest of Brazil. Because the Brazilian fauna suffers from ongoing human impacts both inside and outside protected areas and their buffer zones, inventories of the faunal assemblages in these areas remain vital. Based on field surveys and the examination of museum specimens, we report on the herpetofauna of the buffer zone of Parque Estadual da Serra da Tiririca, located in the Brazilian state of Rio de Janeiro. Across nine sampling areas during 2017 and 2018, we documented 30 species of anurans, one caecilian, 18 snakes, eight lizards, and one crocodilian. This assemblage includes the first record for five species from the protected area. Our inventory offers fundamental information that can promote actions to maintain populations of these taxonomic groups and their habitats within and outside of this protected area.
KEYWORDS: Amphibia; Atlantic Forest; conservation; diversity; protected areas; Squamata; urban forest
... However, the global disappearance of turtles is a worrying phenomenon that has grabbed the attention of environmentalists and scholars due to its significant effects on ecological diversity and the health of ecosystems (Petrov et al., 2023). About 52% of turtle species face extinction, with 20% critically endangered, and 61% designated as threatened by the International Union for Conservation of Nature (IUCN) (Howell et al., 2019;Rhodin et al., 2018;Stanford et al., 2020;IUCN, 2023). The yellow mud turtle (Kinosternon flavescens) is an important species native to North America (Christiansen et al., 1985). ...
The conservation of freshwater turtle species depends on precise and effective monitoring techniques. Environmental DNA (eDNA) analysis is a potential method for identifying cryptic and elusive turtle species in aquatic ecosystems. eDNA analysis can help to identify key regions for conservation efforts and monitor changes in population levels over time. This study aims to evaluate the effectiveness of a rapid eDNA detection method for the yellow mud turtle ( Kinosternon flavescens , an indicator species that is endangered in some states in the USA), which inhabits local oxbow lakes (e.g., resacas) in Cameron County, South Texas. A species-specific nested PCR assay was designed to enhance the detection of yellow mud turtle species. Water samples were collected from five locations within Cameron County for the detection of yellow mud turtle eDNA. Our results revealed the presence of yellow mud turtles in two out of the five surveyed locations. Our study shows great potential for eDNA monitoring for yellow mud turtle species. This study also provides insights on using eDNA monitoring to protect yellow mud turtle species and recommendations for future research and conservation initiatives.
... Chelonians are animals that perform important ecosystem functions and are intrinsically linked in many traditional cultures, from the consumption and seed dispersal of various tree species to the important social role of communities that use river systems as a means of subsistence (Alves et al., 2008;Rhodin et al., 2018). Kinosternon scorpioides (Linnaeus, 1766) popularly known as the scorpion mud turtle and commonly named in Brazil as "Jurará" is a species of chelon widely distributed in the Neotropical region, occurring from Panama, along the Caribbean mountain range to Brazil, covering the entire Amazon forest, eastern mountain ranges of Colombia, Ecuador, and Peru. ...
Kinosternon scorpioides (Linnaeus, 1766) popularly known in Brazil as “Jurará” is a species of chelon that serves as a food resource and source of income for some families in Northeastern Brazil. In that sense, the present study aimed to analyze the metazoan endoparasites infecting K. scorpioides from the Baixada Maranhense, Brazil. Fifteen adult specimens were captured using funnel traps in flooded fields around the Aurá River, close to the city of São Bento-Maranhão. Samples were transported to the Postgraduate Multi-User Research Laboratory- Laboratories in Postgraduate Research/Postgraduate in Animal Science located at the State University of Maranhão- UEMA for parasitological analyses. The results revealed the presence of larvae of Contracaecum sp. infecting the stomach, intestine, and liver, while Eustrongylides sp. was found encysted in the musculature, stomach, intestine, and inside an egg of a gravid female mud turtle. The findings of the present study constitute the first records of these nematodes parasitizing K. scorpioides. Since K. scorpioides is consumed as food for some families in the State of Maranhão, Brazil, and the presence of both parasites with hygienic-sanitary importance, complementary studies should be designed to allow us to understand the relationship between host parasites and whether they could have zoonotic relevance.
... For instance, the recent study from Da Silva et al. [14] using Z&A data represents the first comparative study of ageing in Testudines, a grossly underrepresented taxon in the study of ageing across tetrapods. These findings are particularly important for the conservation of this order as 56.3% (out of the 360 currently recognised species of extant and recently extinct Testudines) of all data-sufficient Testudine species are considered 'Threatened' by the IUCN Red List [82]. ...
Why and how we age are probably two of science's oldest questions, echoing personal beliefs and concerns about our own finitude. From the earliest musings of ancient philosophers to recent pharmacological trials aimed at slowing ageing and prolonging longevity, these questions have fascinated scientists across time and fields of research. Taking advantage of the natural diversity of ageing trajectories, within and across species, this interdisciplinary volume provides a comprehensive view of the recent advances in ageing and longevity through a biodemographic approach. It includes the key facts, theories, ongoing fields of investigation, big questions, and new avenues for research in ageing and longevity, as well as considerations on how extending longevity integrates into the social and environmental challenges that our society faces. This is a useful resource for students and researchers curious to unravel the mysteries of longevity and ageing, from their origins to their consequences, across species, space and time.
... With more than half of chelonian species threatened with extinction (Rhodin et al. 2018), effective conservation efforts are urgently needed for this taxon. Chelonians are long-lived with delayed sexual maturity and high egg and juvenile mortality; thus conservation efforts need to consider years to decades in the future (Gibbons 1987;Congdon et al. 1993;Spencer 2002). ...
Blanding's turtles (Emydoidea blandingii) are a species of conservation concern throughout their natural range. Headstarting is a common chelonian conservation technique in which neonates are reared in managed-care settings before release, but health assessments are rarely incorporated. From 2020 to 2021 we assessed headstarted turtle health pre-release and 1 mo, 1 yr, and 2 yr after release using physical examination, hematology, plasma biochemistry, protein electrophoresis, and pathogen detection in three Illinois counties. Results were compared to wild-reared juveniles in the same habitats. Overall, 767 assessments from 561 turtles were included. Wild-reared and 2 yr post-release headstarts had higher incidence of hemoparasites, asymmetrical nares, and increased creatine kinase and aspartate aminotransferase activities (P<0.05) compared to all other groups. Erythrocyte sedimentation rate and heterophil:lymphocyte ratio were greater, while total leukocyte and lymphocyte counts were lower (P<0.05) in pre-release headstarts compared to wild-reared juveniles. Total solids, albumin, and beta globulins were higher, while the calcium:phosphorous ratio was lower (P<0.05) in pre-release headstarts and wild-reared juveniles vs. other groups. Bile acid levels were highest in pre-release headstarts (P<0.05). Body condition and gamma globulins increased following release, while alpha globulins and the albumin:globulin ratio decreased following release (P<0.05). Two pre-release and one post-release headstart tested positive for Emydomyces testavorans, one post-release headstart was positive for Mycoplasmopsis sp., and nine post-release turtles were positive for adenoviruses. Overall, rearing conditions have a profound and temporally dynamic impact on Blanding's health assessment parameters. Future studies should evaluate long-term impacts on morbidity and mortality to support positive health status and conservation outcomes.
... Chelonians are among the most imperilled species on the planet [12][13][14], and in Australia, nearly half of the described freshwater species are listed as threatened [15]. Threats to global turtle populations include habitat loss, over-harvesting, pollution, poaching, and emerging novel diseases [16][17][18]. ...
The gut microbiota of vertebrates is malleable and may be shaped by both intrinsic and extrinsic factors. Here, the effect that geography has on the cloacal microbiota of two species of Australian freshwater chelonians, eastern longneck turtle (Chelodina longicollis) and Macquarie River turtle (Emydura macquarii), captured from waterbodies with different levels of anthropogenic pressure was investigated. We analysed the microbiota composition, structure and diversity through 16S rRNA gene amplicon sequencing. It was hypothesised that animals from less disturbed environments would harbour a more diverse cloacal microbial population. The cloacal microbiotas from 93 turtles (C. longicollis n = 78; E. macquarii n = 15), from five locations, were analysed. For both species, the most predominant phylum was Proteobacteria. Cloacal microbiota alpha diversity varied significantly between the C. longicollis from all locations, but no differences were found for E. macquarii. In C. longicollis, turtles from wetlands within the centre of Melbourne had the lowest alpha diversity metrics, while the highest alpha diversity values were seen in turtles captured from an undisturbed rural waterbody. Beta diversity, obtained by weighted UniFrac distance, showed significant differences between locations of capture for both species of turtles in this investigation. For C. longicollis, 87 biomarkers were identified responsible for explaining differences between locations, and in E. macquarii, 42 biomarkers were found. This is the first study to explore the cloacal microbiota composition of the eastern longneck turtle and gives greater insight into microbial community structures in Macquarie River turtles. Our study demonstrated that cloacal microbiota composition of freshwater turtles was significantly influenced by locality and that disrupted environments may reduce microbial diversity in C. longicollis. Interestingly, we discovered that the effects of location contrasted significantly between species for alpha diversity with differences discovered for C. longicollis but not E. macquarii. However, for both species, beta diversity was notably influenced by habitat type. These results highlight the need to interpret chelonian microbiota data in the context of geography and human disturbance of the environment.
... Entre os répteis, tartarugas e cágados representam o grupo de vertebrados mais ameaçados do mundo (Liu et al. 2017;Rhodin et al. 2018;Stanford et al. 2020). Das 356 espécies de tartarugas catalogadas no planeta, mais de 60% delas configuram como criticamente ameaçadas, ameaçadas ou vulneráveis na Lista Vermelha da IUCN (Lovich et al. 2018;Rhodin et al. 2017). ...
Introdução: O uso de animais silvestres como pets é uma prática disseminada culturalmente em todo o mundo. Os quelônios neotropicais se destacam por serem frequentemente comercializados, tanto no mercado nacional como internacional. Objetivos: registrar as espécies de quelônios utilizados no comércio de animais de estimação, identificar as regiões onde essa atividade é mais prevalente e avaliar os impactos na conservação das espécies-alvo. Metodologia: realizamos um levantamento bibliográfico entre março e setembro de 2017, utilizando a base de dados Google Acadêmico. Selecionamos 113 estudos, divididos em dois grupos: aqueles que abordaram diretamente o comércio de quelônios; e aqueles que, embora não focassem no uso e comércio, evidenciaram o fluxo global de espécies. Resultados: identificamos 63 espécies de quelônios pertencentes a 10 famílias, registradas para uso e comércio de pets. Essas espécies foram encontradas em cinco regiões do planeta: América Latina, Ásia, Europa, Oceania e América do Norte. Dentre elas, 37 estão listadas na IUCN Red list, abrangendo categorias que vão de Pouco Preocupantes a Criticamente Ameaçadas. Embora uma grande diversidade de quelônios neotropicais tenha sido registrada no comércio de pets, os dados disponíveis ainda são insuficientes para avaliar a extensão dessa atividade. Conclusão: Observamos uma demanda significativa em regiões onde o comércio é culturalmente enraizado ou em áreas economicamente desenvolvidas, com a Ásia e América Latina destacando-se como os principais centros da rota do comércio internacional. Portanto, são necessárias mais pesquisas etnobiológicas para direcionar estratégias de conservação mais eficazes para as espécies alvo do comércio.
... In these instances, it may be necessary to adjust data sampling frequency, the choice in predictor variables, or the inclusion of data from paired sensors, such as GPS, to disentangle these behaviors. Regardless, the effort required to identify the ideal input parameters for a remote nest identification tool for novel chelonian species may be worthwhile, as chelonians are among the most rapidly declining vertebrate groups [110]. ...
Background
Triaxial accelerometers have revolutionized wildlife research by providing an unprecedented understanding of the behavior of free-living animals. Machine learning is often applied to acceleration data to classify diverse animal behaviors across taxa. However, the high frequency, continuous data collection typically favored for behavioral classification studies often generates very large data sets, which may inhibit remote data acquisition and make data storage challenging. Coarse-frequency sampling or non-continuous bursts of acceleration data reduce these problems. To analyze such data, a suite of variables that summarize key features of the behavior of interest can be generated. These variables can then be used in numerous classification approaches, accommodating variation in data collection methods or sampling regimes. We demonstrate the potential for non-continuous accelerometer data to identify long-duration behavior and employ machine learning to classify the nesting behaviors of the critically endangered eastern Santa Cruz giant tortoise (Chelonoidis donfaustoi).
Results
We field validated 112 nesting events from 21 giant tortoises. We then derived summary statistics based on accelerometry (e.g., overall dynamic body acceleration, metrics comparing acceleration before and after the probable event) and used them as inputs for Random Forest and Boosted Regression Tree classification algorithms. Our models produced a harmonic mean of precision and sensitivity (F1-score) of 0.91. We tested the generality of our model and found that the model performs well when applied to both novel individuals and years. The most important variable in accurately classifying data sequences was the proportion of acceleration data bursts above an activity threshold followed by the average overall dynamic body acceleration value of the bursts.
Conclusions
These results demonstrate the feasibility and efficacy of using non-continuous accelerometer data to identify prolonged, biologically relevant behaviors in free-living wildlife. By using summary variables that do not require continuous sampling, this approach facilitates long-term monitoring of animal behavior. Similar methodology has potential to inform priority questions in ecology and conservation, such as predicting wildlife responses to climate change and identifying critical habitats, with applications across diverse species and behaviors.
