February 2022
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114 Reads
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February 2022
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114 Reads
August 2021
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461 Reads
Due to a prolonged civil war (1983-2005 and 2013-2020), the republic of South Sudan in East Africa, which was officially born in 2011, has been one of the least investigated nations of the continent in terms of chelonian diversity, distribution, ecology, and conservation. Since 2017, this nation has been subjected to careful chelonian field investigations, which have allowed us to clarify the current distribution and status of the diversity of tortoises and freshwater turtles within the country. Including historical (pre-2017) records, we have now recorded the presence of nine chelonian species in South Sudan: three Trionychidae (Cyclanorbis elegans, rediscovered in 2017 after having been considered possibly extinct; Cyclanorbis senegalensis and Trionyx triunguis, both widespread and common); two Pelomedusidae (Pelusios adansonii and Pelomedusa schweinfurthi, widespread and common); and five Testudinidae (Stigmochelys pardalis, very common in the southeast; Kinixys belliana, abundant in the south; Kinixys nogueyi, very rare and recorded only from a narrow forest area in the extreme west; Kinixys erosa, very rare and recorded only from a few rainforest sites along the southern border with Uganda). In terms of species richness, the White Nile hydroshed basin is the main hotspot for South Sudan, with its upper (southern) reaches from Juba to the southern border with Uganda being the richest area for chelonian diversity, and therefore the most important area for turtle-oriented protected areas planning. Based on our preliminary investigations, we consider three species to be Critically Endangered at the national level: C. elegans (also globally CR), K. erosa (globally EN), and K. nogueyi (globally provisionally VU). The other six species are Least Concern at the national level. However, all species are subjected to hunting for domestic consumption as the main threat; habitat loss is still a minor problem for chelonians in South Sudan, although logging and timber and non-timber products extraction may affect the forest species in some localities.
July 2021
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230 Reads
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4 Citations
Oryx
The Nubian flapshell turtle (Cyclanorbis elegans; Trionychidae) is one of the most threatened species of turtles in the world and it has been recently rediscovered (year 2017) in a restricted area of South Sudan. Previous studies showed that fishing bycatch and collection of eggs and nesting females for domestic subsistence are the main threats for this species, whereas habitat loss/alteration seems to be a minor threat in South Sudan. During field research conducted in 2020 along the White Nile River and its tributaries (Central Equatoria State), we interviewed local fishermen, as they are important sources of traditional ecological knowledge about this species. During interviews conducted with >300 local community members, we obtained direct information (confirmed by photos of captured individuals) that some individuals were sold by local fishermen to expatriate Chinese residents. Chinese expatriates constitute the main market for the turtles, paying high prices (> 250-400 euro for large individuals) for food and, in one case, for “religious veneration”. These prices are a strong incentive for the impoverished fishing communities along the White Nile river to to catch these turtles. Interviewees also informed us that expatriate Chinese may also export the turtles to Asia for the food trade. We therefore urge the creation of a protected area for these turtles, and a system of monitoring and mitigating the potential detrimental effects that the Asian export market may have on this species.
June 2020
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147 Reads
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3 Citations
Chelonian Conservation and Biology
The Coahuila box turtle (Terrapene coahuila) is an endangered species of chelonian endemic to the Cuatro Ciénegas valley in northern Mexico. It is the only aquatic member of the genus Terrapene and is dependent on permanent and seasonal wetlands. Over the past several decades, T. coahuila populations have declined from habitat loss as the wetlands have dried due to human modification of the valley. We conducted a survey of the status of the species from 2011 to 2018, updating previous estimates of population density and overall population size. We also collected data on sex ratio in each of the 8 wetland study areas in the valley and report a strongly male-biased sex ratio. Our results indicate a total population size of approximately 1791 individuals, based on recorded densities from 0.24 to 3.3 individuals/ha among 539.76 ha of suitable habitat in the 8 wetland areas. This estimate is lower than previous studies indicated, implying direct effects of habitat loss on T. coahuila. If habitat loss due to lowering of the water table continues, this species will become extinct. We recommend conservation measures including upgrading the species' International Union for Conservation of Nature Red List status to Critically Endangered, protecting and restoring key wetlands in the valley, and establishing captive assurance colonies in Mexico.
June 2020
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117 Reads
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1 Citation
Chelonian Conservation and Biology
June 2020
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3,002 Reads
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354 Citations
Current Biology
Turtles and tortoises (chelonians) have been integral components of global ecosystems for about 220 million years and have played important roles in human culture for at least 400,000 years. The chelonian shell is a remarkable evolutionary adaptation, facilitating success in terrestrial, freshwater and marine ecosystems. Today, more than half of the 360 living species and 482 total taxa (species and subspecies combined) are threatened with extinction. This places chelonians among the groups with the highest extinction risk of any sizeable vertebrate group. Turtle populations are declining rapidly due to habitat loss, consumption by humans for food and traditional medicines and collection for the international pet trade. Many taxa could become extinct in this century. Here, we examine survival threats to turtles and tortoises and discuss the interventions that will be needed to prevent widespread extinction in this group in coming decades.
December 2018
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8,913 Reads
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263 Citations
Chelonian Conservation and Biology
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 provisional Red List assessments by the IUCN Tortoise and Freshwater Turtle Specialist Group (TFTSG) of 109 currently unlisted species of tortoises and freshwater turtles, as well as re-assessments of several outdated IUCN Red List assessments. Of all recognized species of turtles and tortoises, this combined analysis indicates that 20.0% are Critically Endangered (CR), 35.3% are Critically Endangered or Endangered (CRþEN), and 51.9% are Threatened (CRþENþVulnerable). Adjusting for the potential threat levels of Data Deficient (DD) species indicates that 56.3% of all data-sufficient species are Threatened. We calculated percentages of imperiled species and modified Average Threat Levels (ATL; ranging from Least Concern = 1 to Extinct = 8) for various taxonomic and geographic groupings. Proportionally more species in the subfamily Geoemydinae (Asian members of the family Geoemydidae) are imperiled (74.2% CRþEN, 79.0% Threatened, 3.89 ATL) compared to other taxonomic groupings, but the families Podocnemididae, Testudinidae, and Trionychidae and the superfamily Chelonioidea (marine turtles of the families Cheloniidae and Dermochelyidae) also have high percentages of imperiled species and ATLs (42.9–50.0% CRþEN, 73.8–100.0% Threatened, 3.44–4.06 ATL). The subfamily Rhinoclemmydinae (Neotropical turtles of the family Geoemydidae) and the families Kinosternidae and Pelomedusidae have the lowest percentages of imperiled species and ATLs (0%–7.4% CRþEN, 7.4%–13.3% Threatened, 1.65–1.87 ATL). Turtles from Asia have the highest percentages of imperiled species (75.0% CRþEN, 83.0% Threatened, 3.98 ATL), significantly higher than predicted based on the regional species richness, due to much higher levels of exploitation in that geographic region. The family Testudinidae has the highest ATL (4.06) of all Testudines due to the extinction of several species of giant tortoises from Indian and Pacific Ocean islands since 1500 CE. The family Testudinidae also has an ATL higher than all other larger polytypic families (higher than 5 species) of Reptilia or Amphibia. The order Testudines is, on average, more imperiled than all other larger orders (� 20 species) of Reptilia, Amphibia, Mammalia, or Aves, but has percentages of CRþEN and Threatened species and an ATL (2.96) similar to those of Primates and Caudata (salamanders).
September 2018
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56 Reads
Meat became a part of the human diet at least as early as 2.5 million years ago, when evidence of stone tool use appears in the fossil record. The fossil evidence does not, however, answer key questions about the evolution of meat eating. The meat‐eating behavior of modern primates is one key area of evidence that can be used to reconstruct the likely patterns of meat eating by early humans. Most modern human populations are omnivorous, as are wild chimpanzees and bonobos. Many nonhuman primate species hunt and eat other small mammals, although none as systematically and with as many implications for human origins as chimpanzees.
September 2018
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30 Reads
Jane Goodall is a pioneering primatologist, author, and social activist who revolutionized the way we look at both great apes and ourselves. She was the first scientist to immerse herself in the lives of wild nonhuman primates on a long‐term basis. She showed that chimpanzees eat meat, use tools, and have kin relations much like those in humans. She maintained her field study in Gombe National Park, Tanzania, from 1960 until the present. Her study of the Gombe chimpanzees is the longest and arguably most important field study of animals ever conducted. Since the 1980s, Goodall has been on a tireless campaign to promote humane practices in our use of nonhuman animals as well as ecosensitive practices in daily life.
July 2018
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93 Reads
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14 Citations
American Journal of Primatology
Habitat fragmentation is a leading threat to global biodiversity. Dispersal plays a key role in gene flow and population viability, but the impact of fragmentation on dispersal patterns remains poorly understood. Among chimpanzees, males typically remain in their natal communities while females often disperse. However, habitat loss and fragmentation may cause severe ecological disruptions, potentially resulting in decreased fitness benefits of male philopatry and limited female dispersal ability. To investigate this issue, we genotyped nearly 900 non‐invasively collected chimpanzee fecal samples across a fragmented forest habitat that may function as a corridor between two large continuous forests in Uganda, and used the spatial associations among co‐sampled genotypes to attribute a total of 229 individuals to 10 distinct communities, including 9 communities in the corridor habitat and 1 in continuous forest. We then used parentage analyses to infer instances of between‐community dispersal. Of the 115 parent–offspring dyads detected with confidence, members of 39% (N = 26) of mother–daughter dyads were found in different communities, while members of 10% (N = 5) of father–son dyads were found in different communities. We also found direct evidence for one dispersal event that occurred during the study period, as a female's sample found first in one community was found multiple times in another community 19 months later. These findings suggest that even in fragmented habitats, chimpanzee males remain in their natal communities while females tend to disperse. Corridor enhancement in unprotected forest fragments could help maintain gene flow in chimpanzees and other species amid anthropogenic pressures.
... What individual differences might be associated with the desire to eat meat ( Figure 1A)? Although our desire for meat is deeply ingrained, both culturally and biologically (Stanford & Bunn, 2001), people nevertheless vary in their commitment to and enjoy ment of eating meat (Piazza et al., 2015). Individuals scoring high on such measures consume more meat and endorse more justifications for eating meat, such as claiming that meat is necessary for good health (Piazza et al., 2015). ...
June 2001
... Such factors could give rise to unintentional patterns on the bones during the defleshing process that seem to be guided not by an individual intention but, as Binford [3] argued, by animal anatomy. In addition, other multiple factors may influence butchery processes, such as the experience of the butcher, prey size, site functionality, seasonality, ground characteristics and/or available human technology including boiling and metal [89,90,92,100,108109110. These variables affect behaviours and, in consequence, may produce a high variability in the resultant cut-marks. ...
June 2001
... Habitat loss and overexploitation (for local subsistence consumption and for the international trade) are the main threats affecting terrestrial and aquatic chelonians worldwide, with most tropical turtles and tortoises now classified as threatened according to the IUCN Red List (e.g., Rhodin et al., 2018;Stanford et al., 2018Stanford et al., , 2020Luiselli et al., 2021;McGovern and Luiselli, 2023). ...
July 2021
Oryx
... Current ecological information about the Coahuila Box Turtle indicates an ~90% decline in the populations over the past 50 years (Brown 1974, Castañeda Gaytan et al. 2020. The wetlands, highly dependent on annual precipitation (Castañeda Gaytán et al. 2020), have also been much reduced (Torres-Vera 2012). ...
June 2020
Chelonian Conservation and Biology
... Future studies can build upon these findings to explore the ecological roles, habitat preferences and potential niche partitioning of P. kobe and its close relatives. Such research will be crucial for developing effective conservation strategies that account for the unique ecological requirements of cryptic species within the Pelomedusa genus and other turtle taxa (Lovich et al. 2018;Stanford et al. 2020). ...
June 2020
Current Biology
... 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). ...
December 2018
Chelonian Conservation and Biology
... This categorization (expected to be local/philopatric or expected to be non-local/ disperser) necessitates an idealized expectation that all adult primates of the dispersing sex for each species were in fact individuals who locationally dispersed (non-locals), and all those of the philopatric sex were individuals who did not disperse (locals). The authors recognize that this is an overly simplified version of a dispersal model; in reality, rates of dispersal from natal groups can vary widely and are dependent on resource availability, social factors, habitat fragmentation and other factors [73,74]. For example, in male-philopatric chimpanzees, male dispersals are virtually unheard of due to lethal intergroup aggression among males [75], but female dispersal rates from natal groups vary from 50% to nearly 100% [76][77][78][79]. ...
July 2018
American Journal of Primatology
... There were Fig. 6 The François' langurs home range in each quarters calculated using a minimum convex polygon (MCP) method also 12 monkeys in Nonggang area, including nine adults, with a home range of 69.3 ha (Table 1) (Zhou 2005); there were seven monkeys in Fusui area, including four adults, with a home range of only 19 ha (Huang et al. 2011). A positive relationship was also found in Rhinopithecus roxellanae in Shennongjia Nature Reserve, where a population of 236 individuals had a home range of 2250 ha, while a small population of 62 individuals had a home range of only 1240 ha (Fan et al. 2019). There were several hundred R. bieti living in high-altitude forest areas, with a home range of 2525 ha (Kirkpatrick 1996). ...
June 2018
动物学研究
... Aquatic Conservation: Marine and Freshwater Ecosystems, 2025 Of freshwater species, aquatic and semi-aquatic turtles are one of the most threatened vertebrate groups in the world (Todd, Willson, and Gibbons 2010), with nearly 40% of species officially listed as threatened under IUCN criteria (i.e. classified as Vulnerable, Endangered or Critically Endangered) (Stanford et al. 2018). Freshwater turtle decline has several non-mutually exclusive causes, essentially related to the loss, modification or fragmentation of habitats resulting from urban development (Gerlach 2008;Marchand and Litvaitis 2004) and the increase of intensive agricultural land use (Saumure and Bider 1998). ...
March 2018
... Reptiles exhibit distinct life stages from juveniles to adults, each characterized by unique physiological demands and developmental requirements [26]. Age-related differences in hormonal levels are thus an important aspect of reptilian endocrinology [27,28]. Juvenile and adult tortoises may exhibit different hormonal profiles due to their varying physiological needs and developmental stages [26,28,29]. ...
September 2017
General and Comparative Endocrinology