scholarly journals Transcending marine turtles: first report of hatching failure in eggs of Amazonian freshwater turtles with symptoms of the fungal emerging disease fusariosis

2021 ◽  
Author(s):  
Ana Sofía Carranco ◽  
Mark A.F. Gillingham ◽  
Kerstin Wilhelm ◽  
María de Lourdes Torres ◽  
Simone Sommer ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Illumina Miseq ◽  
Sea Turtle ◽  
Marine Turtle ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Population Declines ◽  
Turtle Species ◽  
Podocnemis Unifilis ◽  
Conservation Concern

In the last decades fungal pathogens are causing devastating population declines across a broad range of taxa. A newly emerging fungal disease, sea turtle egg fusariosis, caused by members of the Fusarium solani species complex (FSSC), has been reported to be responsible for hatching failure in sea turtles around the world. However, this has not been reported in other non-marine turtle species. Herein we report high hatching failure from eggs symptomatic of fusariosis in the yellow-spotted Amazon river turtle ( Podocnemis unifilis), inhabiting a pristine environment in the Ecuadorian Amazon. We assessed hatching success from eggs symptomatic and asymptomatic of fusariosis ( n = 680 eggs), tested for Fusarium infection by PCR amplifying the TEF-1α gene (n= 68 turtle internal egg swab samples) and sequenced eight amplicons for screening of FSSC membership on an Illumina Miseq. Hatchability was 72% for asymptomatic eggs, whilst only 8% of symptomatic eggs hatched. Eight percent of asymptomatic and 58% of symptomatic eggs tested positive for Fusarium spp. and sequencing revealed that nine sequence variants from three asymptomatic and four symptomatic eggs corresponded to F. keratoplasticum, F. solani and F. falciforme, the three major FSSC pathogens already reported in sea turtle egg fusariosis. Our study therefore suggests that observed hatching failure of eggs showing symptoms of fusariosis is at least partially caused by Fusarium pathogens within FSSC in a freshwater turtle. This report highlights that fusariosis is more widespread among the Testudines order than previously reported and is not limited to sea environments, which is of particular conservation concern.

scholarly journals Plastic ingestion by freshwater turtles: a review and call to action

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Adam G. Clause ◽  
Aaron J. Celestian ◽  
Gregory B. Pauly
Keyword(s):  
Marine Species ◽  
Marine Turtle ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Plastic Pollution ◽  
Potential Threat ◽  
Implementation Quality ◽  
Turtle Species ◽  
Marine Turtles ◽  
Conservation Concern

AbstractPlastic pollution, and especially plastic ingestion by animals, is a serious global issue. This problem is well documented in marine systems, but it is relatively understudied in freshwater systems. For turtles, it is unknown how plastic ingestion compares between marine and non-marine species. We review the relevant turtle dietary literature, and find that plastic ingestion is reported for all 7 marine turtle species, but only 5 of 352 non-marine turtle species. In the last 10 years, despite marine turtles representing just 2% of all turtle species, almost 50% of relevant turtle dietary studies involved only marine turtles. These results suggest that the potential threat of plastic ingestion is poorly studied in non-marine turtles. We also examine plastic ingestion frequency in a freshwater turtle population, finding that 7.7% of 65 turtles had ingested plastic. However, plastic-resembling organic material would have inflated our frequency results up to 40% higher were it not for verification using Raman spectroscopy. Additionally, we showcase how non-native turtles can be used as a proxy for understanding the potential for plastic ingestion by co-occurring native turtles of conservation concern. We conclude with recommendations for how scientists studying non-marine turtles can improve the implementation, quality, and discoverability of plastic ingestion research.

Conservation genetics of the endangered Spotted Turtle (Clemmys guttata) illustrate the risks of “bottleneck tests”

2014 ◽  
Vol 92 (2) ◽  
pp. 149-162 ◽  
Author(s):  
Christina M. Davy ◽  
Robert W. Murphy
Keyword(s):  
Population Genetics ◽  
Freshwater Turtles ◽  
Population Declines ◽  
Isolated Populations ◽  
Principal Coordinates Analysis ◽  
Turtle Species ◽  
Principal Coordinates ◽  
Clemmys Guttata ◽  
Spotted Turtle ◽  
Cast Doubt

Studies of population genetics in turtles have suggested that turtles do not experience genetic impacts of bottlenecks as strongly as expected. However, recent studies cast doubt on two commonly used tests implemented in the program BOTTLENECK, suggesting that these findings should be re-evaluated. The Spotted Turtle (Clemmys guttata (Schneider, 1792)) is endangered both globally and within Canada, but genetic data required to develop effective recovery strategies are unavailable. Here, we conducted the first study of population genetic structure in C. guttata. We then used multiple small populations of C. guttata as replicates to test whether the commonly used program BOTTLENECK could detect the genetic signature of bottlenecks in our study populations, which are all thought to have experienced significant declines in the past 2–3 generations (75 years). Turtles (n = 256) were genotyped at 11 microsatellite loci. A suite of Bayesian population genetics analyses and a principal coordinates analysis identified a minimum of 6 distinct genetic populations and a maximum of 10 differentiated subpopulations across the sampled Canadian range of C. guttata, which corresponded to demographically independent units. BOTTLENECK failed to detect population declines. A literature review found that bottleneck tests in 17 of 18 previous genetic studies of tortoises and freshwater turtles were based on suboptimal sampling, potentially confounding their results. High retention of genetic diversity (allelic richness and heterozygosity) in isolated populations of C. guttata and other turtle species is encouraging for species recovery, but conclusions about the prevalence of genetic bottlenecks in such populations should be re-examined.

scholarly journals The Olive Ridley Project (ORP): A successful example of how to engage researchers, conservation practitioners and civil society

2021 ◽  
Vol 5 (2) ◽  
Author(s):  
Martin Stelfox ◽  
Mercedes Martin-Cereceda ◽  
Karim Vahed ◽  
Jillian Hudgins ◽  
Stephanie Köhnk ◽  
...  
Keyword(s):  
Spatial Ecology ◽  
Community Education ◽  
Knowledge Exchange ◽  
Sustainable Use ◽  
Sea Turtle ◽  
Marine Turtle ◽  
Olive Ridley ◽  
Turtle Species ◽  
Research Engagement ◽  
The Uk

The Olive Ridley Project (ORP) was set up to protect sea turtles and their habitats. The project was formed in 2013, and it became a registered charity in the UK in 2016. From its inception, ORP took a multidisciplinary approach to achieve its goals. Part of its objectives, and the reason why the charity came to fruition, are related to the issue of olive ridley sea turtle (Lepidochelys olivacea) entanglement in abandoned, lost or discarded fishing gear (also known as ‘ghost gear’ or ‘ghost nets’), and the search for ghost gear and turtle entanglement ‘hot spots’ throughout the Indian Ocean. The initial ORP research questions were soon challenged by societal interests to develop inclusive educational programmes in local communities and tourist resorts that could raise awareness about the need for conservation of all sea turtle species. In February 2017, ORP opened the first veterinarian-run, fully equipped Marine Turtle Rescue Centre in the Maldives, bringing together the work of researchers, citizen scientists, volunteers, environmentalists, marine biologists and veterinarians. The present work of ORP sits on a strong and scientifically robust collaborative plan. Current ORP research projects range from sea turtle population analyses, spatial ecology, rehabilitation of injured and sick individuals, epibiont parasite analyses, precise turtle identification through photo-ID research, linking ghost gear to responsible fisheries, and analyses of ghost gear drift patterns. The programme enhances community education and outreach by engaging schoolchildren, organizing workshops, promoting sustainable use of ghost gear waste, and training citizen scientists and local fishing communities. The ORP programme encompasses many principles of research engagement, effectively combining scientific knowledge, education and action. This article explores all stages of the process (from research planning and design, to knowledge exchange and inter- and trans-disciplinary impact assessments), describing the active engagement originated by the ORP initiative. A reflective insight into the learning, enrichment and challenges of engaging researchers and community actors is also included, considering the current social and scientific framework.

Tetranucleotide markers from the loggerhead sea turtle (Caretta caretta) and their cross-amplification in other marine turtle species

2008 ◽  
Vol 10 (3) ◽  
pp. 577-580 ◽  
Author(s):  
Brian M. Shamblin ◽  
Brant C. Faircloth ◽  
Mark G. Dodd ◽  
Dean A. Bagley ◽  
Llewellyn M. Ehrhart ◽  
...  
Keyword(s):  
Caretta Caretta ◽  
Sea Turtle ◽  
Marine Turtle ◽  
Loggerhead Sea Turtle ◽  
Turtle Species ◽  
Cross Amplification

scholarly journals Population status and distribution of freshwater turtles in Taiwan

Oryx ◽  
2010 ◽  
Vol 44 (2) ◽  
pp. 261-266 ◽  
Author(s):  
Tien-Hsi Chen ◽  
Kuang-Yang Lue
Keyword(s):  
Native Species ◽  
Mainland China ◽  
Iucn Red List ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Chinese Market ◽  
Negative Effects ◽  
Turtle Species ◽  
Mauremys Mutica ◽  
Effective Conservation

AbstractBecause of burgeoning demand in the Chinese market and extensive habitat loss more than half of the freshwater turtle and tortoise species in Asia are categorized as Endangered or Critically Endangered on the IUCN Red List. To investigate the distribution and status of the native freshwater turtle species of Taiwan a trapping programme was conducted during 2001–2007, yielding a total of 1,828 individuals of four native species at 103 sites. Mauremys sinensis was the most abundant and widely distributed species; it was collected from 70 sites and accounted for 78.6% of all turtles captures. Mauremys mutica comprised 17.8% at 46 sites. Pelodiscus sinensis were captured in low numbers at 19 sites. No Mauremys reevesii were collected on the main island of Taiwan but the species was found on Kinmen Island near mainland China. Capture success was low at most sites and overall sex ratios were significantly male-biased in all species, suggesting that the freshwater turtles have suffered from the negative effects of habitat disturbance and extensive exploitation. Effective conservation measures are urgently required to ensure the viability of the native freshwater turtle species of Taiwan.

scholarly journals Beyond Sea Turtles: Fusarium keratoplasticum in Eggshells of Podocnemis unifilis, a Threatened Amazonian Freshwater Turtle

2021 ◽  
Vol 7 (9) ◽  
pp. 742
Author(s):  
Joaquina M. García-Martín ◽  
Jullie M. Sarmiento-Ramírez ◽  
Javier Diéguez-Uribeondo
Keyword(s):  
Wildlife Conservation ◽  
Wide Spectrum ◽  
Sea Turtles ◽  
Population Decline ◽  
Pathogenic Fungi ◽  
Sea Turtle ◽  
Molecular Data ◽  
Protective Role ◽  
Freshwater Turtle ◽  
Podocnemis Unifilis

The endangered yellow-spotted river turtle (Podocnemis unifilis) has experienced a dramatic population decline in the Ecuadorian Amazonia, mainly due to overexploitation of its eggs. To reverse this trend, the Wildlife Conservation Society has developed a head-start program in Yasuní National Park since 2008, but the potential risk that microbes associated with its eggs might represent for hatching success has not been evaluated yet. Members of the Fusarium solani species complex (FSSC) are involved in egg failure in sea turtles under natural and hatchery conditions, but their role in infecting the eggs of P. unifilis is unknown. In this study, we collected eggshells of P. unifilis and obtained 50 fungal and bacterial isolates. Some potentially pathogenic fungi of the genera Fusarium, Penicillium and Rhizopus were identified based on molecular data. Most importantly, the sea turtle pathogenic species F. keratoplasticum not only was present, but it was the most frequently found. Conversely, we have also isolated other microorganisms, such as Pseudomonas or Phoma-like species, producing a wide spectrum of antifungal compounds that may have a protective role against fungal diseases. Our survey provides useful information on potential pathogens found in P. unifilis eggshells, upon which the success of conservation programs may depend.

scholarly journals Impacts of dams on freshwater turtles: a global review to identify conservation solutions

2021 ◽  
Author(s):  
Andrea Barcenas-Garcia ◽  
Fernanda Michalski ◽  
William H. Morgan ◽  
Rebecca K. Smith ◽  
William J. Sutherland ◽  
...  
Keyword(s):  
Freshwater Ecosystems ◽  
Freshwater Turtle ◽  
Tropical Species ◽  
Life History Stage ◽  
Freshwater Turtles ◽  
Tropical Regions ◽  
Turtle Species ◽  
Threat Status ◽  
Dam Impacts ◽  
The Impact

Dams create many impacts on freshwater ecosystems and biodiversity. Freshwater turtles are at direct and indirect risk due to changes caused by damming including the loss of terrestrial and aquatic nesting and feeding habitats, changes to resource availability and reduced dispersal. We reviewed the global scientific literature that evaluated the impact of dams on freshwater turtles, and carried out additional searches of literature published in seventeen languages for studies evaluating actions to mitigate the impact of dams. The search produced 43 published articles documenting dam impacts on 29 freshwater turtle species from seven families (Chelidae, Chelydridae, Emydidae, Geoemydidae, Kinosternidae, Podocnemididae and Trionychidae) in 13 countries. More than a third of studies (41.9%, n = 18) focused on nine North American species of the Emydidae. Few studies were found from Europe and Asia and none from Africa. The number of studies, life-history stage studied and threat status differed significantly between temperate and tropical latitudes. Most studies were from temperate latitudes, where studies focused more on adults and less threatened species compared with tropical latitudes. Studies evaluated dam impacts as barriers and changes to water flow and quality, but no studies were found that assessed turtles and changes to land cover or mercury caused by dams. More than half of the studies (59%, n = 24) suggested actions to help mitigate dam impacts. Yet, only four studies on three temperate and one tropical species documented the effect of interventions (dam removal, flow management, artificial pond maintenance and community-based action). These findings demonstrate a lack of documented evidence evaluating dam impacts on freshwater turtles particularly in tropical regions. This lack of evidence reinforces the importance of strengthening and maintaining robust long-term studies of freshwater turtles needed to develop effective conservation actions for this group of vertebrates.

Body temperature of free-living freshwater turtles, Hydromedusa maximiliani (Testudines, Chelidae)

2006 ◽  
Vol 27 (3) ◽  
pp. 464-468 ◽  
Author(s):  
Fernando Martins ◽  
Franco Souza
Keyword(s):  
Body Temperature ◽  
Water Temperature ◽  
Stream Water ◽  
Life Stage ◽  
Freshwater Turtle ◽  
Freshwater Turtles ◽  
Body Temperatures ◽  
Turtle Species ◽  
Mountainous Regions ◽  
Main Factor

AbstractField body temperatures of the Maximilian's snake-necked turtle, Hydromedusa maximiliani, a small freshwater turtle species endemic to Atlantic rainforest mountainous regions in Brazil, were studied. Turtle body temperatures and water temperatures were significantly related, but turtle body temperature averaged 1°C higher than stream water temperature, this difference being statistically significant. A multivariate model revealed that only water temperature was significantly related to turtle body temperature while body size had no effect. There was no effect of sex and life stage on turtle body temperature, implying that water temperature was the main factor determining body temperatures. Thermoconformity was verified for all sampled individuals. The broad implications of these results are also discussed.

scholarly journals Emergence of a Novel Pathogenic Poxvirus Infection in the Endangered Green Sea Turtle (Chelonia mydas) Highlights a Key Threatening Process

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 219
Author(s):  
Subir Sarker ◽  
Christabel Hannon ◽  
Ajani Athukorala ◽  
Helle Bielefeldt-Ohmann
Keyword(s):  
Sequence Data ◽  
Sequence Similarity ◽  
Chelonia Mydas ◽  
Sea Turtle ◽  
Marine Turtle ◽  
In Vivo Studies ◽  
Avian Host ◽  
The Novel ◽  
Green Sea Turtle ◽  
Turtle Species

Emerging viral disease is a significant concern, with potential consequences for human, animal and environmental health. Over the past several decades, multiple novel viruses have been found in wildlife species, including reptiles, and often pose a major threat to vulnerable species. However, whilst a large number of viruses have been described in turtles, information on poxvirus in cheloniids remains scarce, with no molecular sequence data available to date. This study characterizes, for the first time, a novel poxvirus, here tentatively designated cheloniid poxvirus 1 (ChePV-1). The affected cutaneous tissue, recovered from a green sea turtle (Chelonia mydas) captured off the Central Queensland coast of Australia, underwent histological examination, transmission electron microscopy (TEM), DNA extraction and genomic sequencing. The novel ChePV-1 was shown to be significantly divergent from other known poxviruses and showed the highest sequence similarity (89.3%) to avipoxviruses (shearwater poxvirus 2 (SWPV2)). This suggests the novel ChePV-1 may have originated from a common ancestor that diverged from an avipoxvirus-like progenitor. The genome contained three predicted unique genes and a further 15 genes being truncated/fragmented compared to SWPV2. This is the first comprehensive study that demonstrates evidence of poxvirus infection in a marine turtle species, as well as a rare example of an avipoxvirus crossing the avian-host barrier. This finding warrants further investigations into poxvirus infections between species in close physical proximity, as well as in vitro and in vivo studies of pathogenesis and disease.

scholarly journals Characteristics of Shell Bone as an Identification Tool for Turtle Species (Reptiles: Testudines) in Java, Borneo, and Sumatra

2020 ◽  
Vol 5 (1) ◽  
pp. 35
Author(s):  
Donan Satria Yudha ◽  
Fidelis Triki Sadewa Aritona ◽  
Rury Eprilurahman
Keyword(s):  
Sea Turtle ◽  
Morphological Characters ◽  
Visual Observation ◽  
Freshwater Turtle ◽  
Illegal Trade ◽  
Turtle Species ◽  
Long Time ◽  
Softshell Turtle ◽  
Different Characteristics ◽  
Identification Tool

There are 42 species of turtles; including sea turtle, freshwater turtle, tortoise, and softshell turtle (Reptilia: Testudines) living in Indonesia today. Turtles have economic values for quite a long time and it has led to illegal trade such as smuggling of carapace and plastron bones. Identification is needed to find out more details about the turtle species. Turtles have shells as unique features with different characteristics on each species. Shell’s identification usually relies on the shape of carapace and plastron. The purpose of this research is to understand turtle shell morphological characters and determine the diagnostic characters of each species. We conducted visual observation on specimen collections from the Laboratory of Animal Systematics, Faculty of Biology, Universitas Gadjah Mada and Museum of Biology, Faculty of Biology, Universitas Gadjah Mada. The result shows that each turtle species have their own unique shell bone’s characters, therefore it can be used to determine each turtle species of Indonesia.

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