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1.
Sci Total Environ ; 740: 140042, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927538

RESUMO

There is increasing interest in understanding potential impacts of complex pollutant profiles to long-lived species such as the green sea turtle (Chelonia mydas), a threatened megaherbivore resident in north Australia. Dietary ingestion may be a key exposure route for metals in these animals and marine plants can accumulate metals at higher concentrations than the surrounding environment. We investigated concentrations of 19 metals and metalloids in C. mydas forage samples collected from a group of offshore coral cays and two coastal bays over a period of 2-3 years. Although no samples exceeded sediment quality guidelines, coastal forage Co, Fe, and V concentrations were up to 2-fold higher, and offshore forage Sr concentrations were ~3-fold higher, than global seagrass means. Principal Component Analysis differentiated coastal bay from coral cay forage according to patterns consistent with underlying terrigenous-type or marine carbonate-type sediment geochemistry, such that coastal bay forage was higher in Fe, Co, Mn, Cu, and Mo (and others) but forage from coral cays was higher in Sr and U. Forage from the two coastal bays was differentiated according to temporal variation in metal profiles, which may be associated with a more episodic sediment disturbance regime in one of the bays. For all study locations, some forage metal concentrations were higher than previously reported in the global literature. Our results suggest that forage metal profiles may be influenced by the presence of some metals in insoluble forms or bound to ultra-fine sediment particles adhered to forage surfaces. Metal concentrations in Great Barrier Reef forage may be present at levels higher than expected from the global seagrass literature and appear strongly influenced by underlying sediment geochemistry.


Assuntos
Antozoários , Metais Pesados/análise , Tartarugas , Poluentes Químicos da Água/análise , Animais , Austrália , Baías , Monitoramento Ambiental , Sedimentos Geológicos
2.
PLoS One ; 15(8): e0237596, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785283

RESUMO

Blood was collected from wild captured green and Kemp's ridley turtles off the west coast of Florida, USA. Blood gases and biochemical values were analyzed using a point of care (POC) device in the field. Analytes include pH, partial pressure of carbon dioxide (pCO2), partial pressure of oxygen (pO2), total carbon dioxide (TCO2), bicarbonate (HCO3), base excess (BE), oxygen saturation (sO2), lactate, sodium (Na), potassium (K), chloride (Cl), total carbon dioxide (TCO2), anion gap, ionized calcium, glucose, blood urea nitrogen (BUN), creatinine (Crea), hematocrit (Hct), and hemoglobin (Hb). These are novel data for wild healthy Kemp's ridley turtles, and results for green turtles were generally consistent with past studies of green turtles with exceptions primarily in blood gas values. Ninety percent of the green turtles had fibropapillomatosis (FP), but none of the blood analytes were correlated with disease severity. Only BUN was correlated with weight of green turtles, and there was no correlation between blood parameters and weight of Kemp's ridley turtles. This study provides data that are useful in understanding the physiologic status of sea turtles specific to this region, allowing for comparisons to other populations, life stages, and disease states.


Assuntos
Gasometria/veterinária , Nitrogênio da Ureia Sanguínea , Oxigênio/metabolismo , Tartarugas/metabolismo , Veias/metabolismo , Animais , Bicarbonatos/análise , Dióxido de Carbono/análise , Potássio/análise , Sódio/análise , Tartarugas/classificação
3.
Environ Sci Pollut Res Int ; 27(31): 39651-39656, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32808129

RESUMO

The concentrations of cadmium (Cd), mercury (Hg) and lead (Pb) were determined in muscular tissue of eleven loggerhead turtles (Caretta caretta) from the Balearic Islands (Spain, Western Mediterranean). The metal levels found in the present study were similar or lower than concentrations detected in Andalusia (mainland Spain), Italy, Canary Islands (Spain) or Japan. As the main source of metals in the loggerhead turtle is the diet, low metal burdens could be explained by its opportunistic feeding way. No significant differences were found in metal concentrations between juveniles and subadults in any of the heavy metals analysed. Furthermore, no significant correlation was detected between heavy metal concentrations and straight carapace length (SCL) of the studied individuals. These results could derive from the homogeneity in age and size of the turtles sampled, so further studies including adults are needed in order to assess the heavy metal accumulation with turtle growth.


Assuntos
Metais Pesados/análise , Tartarugas , Poluentes Químicos da Água/análise , Animais , Itália , Japão , Mar Mediterrâneo , Espanha
4.
PLoS One ; 15(8): e0236628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756577

RESUMO

The soundscape features of the marine environment provide crucial information about ecosystem health for many species, and they are defined by the local biological, geophysical, and anthropogenic components. In this study, we investigated the soundscape at green turtle neritic foraging habitats in Fiji, South Pacific, with the aims of characterizing the contribution of each component and of comparing the levels of acoustic pressure among sites with different abundances of sea turtles. Four sites were selected at two islands, and one hydrophone was deployed at each site. Generalized additive models highlighted that sound pressure levels (SPLs) at low frequencies (125-250 Hz) were especially affected by wind conditions, while at higher frequencies (>250 Hz) SPLs were mostly influenced by fish and crustacean acoustic activity. Higher abundances of green turtles were found at sites with the highest levels of SPLs and the highest number of acoustic emissions by fishes and crustaceans but were not related to maximum seagrass and macroalgae coverage, or the highest number of fish. The selected coastal habitats have negligible anthropogenic noise, thus this study informs physiological and behavioral studies of the acoustic signatures that sea turtles might target and provides a baseline against which potential impact of soundscape changes on sea turtle spatial abundance and distribution can be evaluated.


Assuntos
Acústica , Ruído , Tartarugas/fisiologia , Animais , Ecossistema , Monitoramento Ambiental , Fiji , Peixes/fisiologia
5.
Ecol Lett ; 23(10): 1479-1487, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32790233

RESUMO

Quantifying sublethal effects of plastics ingestion on marine wildlife is difficult, but key to understanding the ontogeny and population dynamics of affected species. We developed a method that overcomes the difficulties by modelling individual ontogeny under reduced energy intake and expenditure caused by debris ingestion. The predicted ontogeny is combined with a population dynamics model to identify ecological breakpoints: cessation of reproduction or negative population growth. Exemplifying this approach on loggerhead turtles, we find that between 3% and 25% of plastics in digestive contents causes a 2.5-20% reduction in perceived food abundance and total available energy, resulting in a 10-15% lower condition index and 10% to 88% lower total seasonal reproductive output compared to unaffected turtles. The reported plastics ingestion is insufficient to impede sexual maturation, but population declines are possible. The method is readily applicable to other species impacted by debris ingestion.


Assuntos
Tartarugas , Poluentes da Água/análise , Animais , Animais Selvagens , Monitoramento Ambiental , Plásticos , Dinâmica Populacional
6.
PLoS One ; 15(7): e0236888, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735637

RESUMO

Maximum lifespan for most animal species is difficult to define. This is challenging for wildlife management as it is critical for estimating important aspects of population biology such as mortality rate, population viability, and period of reproductive potential. Recently, it has been shown cytosine-phosphate-guanine (CpG) density is predictive of maximum lifespan in vertebrates. This has made it possible to predict lifespan in long-lived species, which are generally the most intractable. In this study, we use gene promoter CpG density to predict the lifespan of five marine turtle species. Marine turtles are a particularly difficult group for lifespan estimation because of their migratory behaviour, longevity and high juvenile mortality rates, which all restrict individual tracking over their lifespan. Sanger sequencing was used to determine the CpG density in selected promoters. We predicted the lifespans for marine turtle species ranged from 50.4 years (flatback turtle, Natator depressus) to 90.4 years (leatherback turtle, Dermochelys coriacea). These lifespan predictions have broad applications in marine turtle research such as better understanding life cycles and determining population viability.


Assuntos
Longevidade/genética , Regiões Promotoras Genéticas , Tartarugas , Animais , Genômica , Vertebrados/genética
7.
Sci Total Environ ; 739: 140176, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758958

RESUMO

Persistent organic pollutants (POP) are toxic substances for wildlife and people. The Kemp's Ridley sea turtle Lepidochelys kempii is an endangered species with limited distribution in the Gulf of Mexico (GM), a marine ecosystem that has been perturbed by a variety of anthropogenic activities. In this work, the concentrations of ten organochlorine pesticides (OP), eight polychlorinated biphenyls (PCB), and atrazine were determined in the plasma of Kemp's Ridley sea turtles that nest in Playa Rancho Nuevo Sanctuary, Tamaulipas, Mexico. Seventy-nine blood samples were collected from female turtles during the 2015-2016 nesting season. Samples were extracted with a focalized ultrasonic sound technique and analyzed through Gas Chromatography coupled to a Mass Spectrometer. POP with the highest percentage of detection were atrazine > PCB 52 > PCB 153 > DDE > alpha endosulfan > DDD > alpha HCH > DDT. There is no linear correlation between the detected POP levels in the Kemp's Ridley sea turtle plasma and its curve carapace length (CCL). When comparing 2015 and 2016 POP concentrations, there were statistically significant differences in atrazine (p < 0.05, R2 = 0.069), PCB 52 (p < 0.05, R2 = 0.0051) and ∑POP (p < 0.05, R2 = 0.0001) and, no statistically significant differences in alpha endosulfan (p < 0.05, R2 = 0.0294), DDE (p < 0.05, R2 = 0.0315) and PCB 153 (p < 0.05, R2 = 0.0036). The reported POP values of this work are one of the few registered for Kemp's Ridley sea turtle in the GM and the first for atrazine levels. These levels were higher than those reported for other sea turtle species from America, Africa, and Europe, which demonstrates a deteriorated health status of the GM marine ecosystem.


Assuntos
Poluentes Ambientais , Tartarugas , África , Animais , Ecossistema , Europa (Continente) , Feminino , Golfo do México
8.
Mar Pollut Bull ; 158: 111390, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753176

RESUMO

Radionuclides from 1950s weapons testing at the Montebello Islands, Western Australia, may impact sea turtle embryos incubating within eggs laid in contaminated sands or be taken up into adult body tissues where they can contribute to radiation dose over a turtles' 60+ year lifespan. We measured plutonium in all local samples including turtle skin, bones, hatchlings, eggshells, sea sediments, diet items and beach sands. The amount of Pu in developing embryos/hatchling samples was orders of magnitude lower than that in the surrounding sands. These contaminated sands caused most dose to eggs (external dose from 137Cs, 152Eu), while most of the dose to adults was from internalised radionuclides (98%). While current dose rates are relatively low, local dose rates were high for about ten years following the 1950s detonations and may have resulted in lethality or health impacts to a generation of turtles that likely carry biomarkers today.


Assuntos
Plutônio/análise , Tartarugas , Poluentes Radioativos da Água/análise , Animais , Sedimentos Geológicos , Ilhas , Austrália Ocidental
9.
Proc Biol Sci ; 287(1932): 20200992, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32752987

RESUMO

Most organisms are exposed to bouts of warm temperatures during development, yet we know little about how variation in the timing and continuity of heat exposure influences biological processes. If heat waves increase in frequency and duration as predicted, it is necessary to understand how these bouts could affect thermally sensitive species, including reptiles with temperature-dependent sex determination (TSD). In a multi-year study using fluctuating temperatures, we exposed Trachemys scripta embryos to cooler, male-producing temperatures interspersed with warmer, female-producing temperatures (heat waves) that varied in either timing during development or continuity and then analysed resulting sex ratios. We also quantified the expression of genes involved in testis differentiation (Dmrt1) and ovary differentiation (Cyp19A1) to determine how heat wave continuity affects the expression of genes involved in sexual differentiation. Heat waves applied during the middle of development produced significantly more females compared to heat waves that occurred just 7 days before or after this window, and even short gaps in the continuity of a heat wave decreased the production of females. Continuous heat exposure resulted in increased Cyp19A1 expression while discontinuous heat exposure failed to increase expression in either gene over a similar time course. We report that even small differences in the timing and continuity of heat waves can result in drastically different phenotypic outcomes. This strong effect of temperature occurred despite the fact that embryos were exposed to the same number of warm days during a short period of time, which highlights the need to study temperature effects under more ecologically relevant conditions where temperatures may be elevated for only a few days at a time. In the face of a changing climate, the finding that subtle shifts in temperature exposure result in substantial effects on embryonic development becomes even more critical.


Assuntos
Temperatura Alta , Processos de Determinação Sexual , Tartarugas/fisiologia , Animais , Mudança Climática , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Fenótipo , Diferenciação Sexual , Razão de Masculinidade
10.
PLoS One ; 15(7): e0236513, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726804

RESUMO

Epizoic diatoms form an important part of micro-epibiota of marine vertebrates such as whales and sea turtles. The present study explores and compares the diversity and biogeography of diatom communities growing on the skin and shell of loggerhead sea turtles (Caretta caretta) from four different localities: Adriatic Sea (Croatia), Ionian Sea (Greece), South Africa and Florida Bay (USA) using both light and scanning electron microscopy. We observed almost 400 diatom taxa belonging to more than 100 genera. Diatom communities from Greece and Croatia showed the highest similarity and were statistically different from those recorded from South Africa and Florida. Part of this variation could be attributed to differences in sampling techniques; however, we believe that geography had an important role. In general, contrary to several previous observations from sea turtles, the presumably exclusively epizoic diatoms contributed less than common benthic taxa to the total diatom flora, which might have been related to the loggerhead feeding behavior. Moreover, skin samples differed from carapace samples in having a distinct diatom composition with a higher proportion of the putative true epizoonts. Our results indicate that epizoic diatom communities differ according to loggerhead geographical location and substrate (skin vs. carapace). The relative abundances of common benthic diatoms and putative exclusive epizoic taxa may inform about sea turtle habitat use or behavior though detailed comparisons among different host species have yet to be performed.


Assuntos
Diatomáceas/crescimento & desenvolvimento , Tartarugas/fisiologia , Animais , Biodiversidade , Análise por Conglomerados , Croácia , Ecossistema , Florida , Grécia , Microscopia Eletrônica de Varredura , África do Sul
11.
Aust Vet J ; 98(10): 511-516, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32643182

RESUMO

OBJECTIVE: To characterise intramuscular ketamine-medetomidine-tramadol anaesthesia in hatchling green sea turtles (Chelonia mydas). STUDY DESIGN: Prospective clinical trial. ANIMALS: Ten hatchling green sea turtles. MATERIALS AND METHODS: Prior to anaesthesia, cardiopulmonary parameters, cloacal temperature, and venous blood gas and biochemistry were obtained from hatchling green sea turtles while they were being gently restrained. Animals were then anaesthetised with ketamine (5 mg kg-1 ), medetomidine (0.05 mg kg-1 ) and tramadol (5 mg kg-1 ) via intramuscular injection. Turtles were checked for the depth of anaesthesia at five-min intervals by recording reflexes (righting, palpebral, pinch, cloacal) and measuring heart rate, respiratory rate and cloacal temperature. After 20 min, a second venous blood sample was obtained for further blood gas and biochemical analysis and the medetomidine was antagonised using atipamezole (5:1 medetomidine, 0.25 mg kg-1 ). RESULTS: All turtles were successfully anaesthetised with a mean time to induction of 3.4 min (±1). In all animals, a loss of reflexes (except for palpebral reflex) and voluntary movement was observed for the entire 20 min. Anaesthesia resulted in marked apnoea for the duration of the procedure. Venous blood gas and biochemistry analysis indicated that a 20 min period of apnoea had no measurable effects on venous blood gas results. All turtles recovered uneventfully after atipamazole antagonisation, with a mean time to first breath 4.5 min (±3.7), and mean recovery time 15.5 min (±15.4). CONCLUSIONS AND CLINICAL RELEVANCE: Intramuscular ketamine-medetomidine-tramadol, antagonised with atipamazole appears to be an effective anaesthetic protocol in hatchling green sea turtles for short procedures with no deleterious effects on venous blood gases or biochemistry.


Assuntos
Anestesia/veterinária , Ketamina , Tramadol , Tartarugas , Anestésicos Combinados , Animais , Injeções Intramusculares/veterinária , Medetomidina , Estudos Prospectivos
12.
Proc Biol Sci ; 287(1930): 20200220, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32605516

RESUMO

For decades, fisheries have been managed to limit the accidental capture of vulnerable species and many of these populations are now rebounding. While encouraging from a conservation perspective, as populations of protected species increase so will bycatch, triggering management actions that limit fishing. Here, we show that despite extensive regulations to limit sea turtle bycatch in a coastal gillnet fishery on the eastern United States, the catch per trip of Kemp's ridley has increased by more than 300% and green turtles by more than 650% (2001-2016). These bycatch rates closely track regional indices of turtle abundance, which are a function of increased reproductive output at distant nesting sites and the oceanic dispersal of juveniles to near shore habitats. The regulations imposed to help protect turtles have decreased fishing effort and harvest by more than 50%. Given uncertainty in the population status of sea turtles, however, simply removing protections is unwarranted. Stock-assessment models for sea turtles must be developed to determine what level of mortality can be sustained while balancing continued turtle population growth and fishing opportunity. Implementation of management targets should involve federal and state managers partnering with specific fisheries to develop bycatch reduction plans that are proportional to their impact on turtles.


Assuntos
Conservação dos Recursos Naturais/métodos , Pesqueiros , Tartarugas , Animais , Ecossistema , Oceanos e Mares
13.
Anim Cogn ; 23(5): 989-998, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32617750

RESUMO

Lateralization represents a key property of many behavioural traits, with the right and left sides of the brain providing different and integrative functions. Common ecological contexts where lateralization can be observed are foraging and predatory ones, where both visual and auditory lateralization may provide advantages such as faster response and increasing neural processing capacity. This is crucial in selecting a safe refuge during a predatory attack and may strongly affect the outcome of predator-prey interactions. For animals like turtles, a critical condition may occur when they are overturned on their own shell, which causes difficulties in breathing and thermoregulation, making them more vulnerable to predators. Therefore, the ability to right is a critical adaptive component related to survival in aquatic turtles, which has been observed to be lateralized. However, an overlooked feature of behavioural lateralization is its possible relationship with asymmetry in external morphology. Here we investigated this topic in freshwater European pond turtles Emys orbicularis, looking at a possible relation between lateralization in righting behaviour response and asymmetry in the shape of turtles' plastron and carapace. Righting performance (total time needed to completely turn) appeared to depend on shell shape. We found that none of the morphometric variables was related to a lateralization index calculated as the first side from which turtles tried to right. However, a strong negative correlation between the asymmetry index of plastron and the turning direction emerged, with more symmetric animals tending to turn to the right side.


Assuntos
Tartarugas , Animais , Água Doce
14.
BMC Evol Biol ; 20(1): 81, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650718

RESUMO

BACKGROUND: The origin of turtles and crocodiles and their easily recognized body forms dates to the Triassic and Jurassic. Despite their long-term success, extant species diversity is low, and endangerment is extremely high compared to other terrestrial vertebrate groups, with ~ 65% of ~ 25 crocodilian and ~ 360 turtle species now threatened by exploitation and habitat loss. Here, we combine available molecular and morphological evidence with statistical and machine learning algorithms to present a phylogenetically informed, comprehensive assessment of diversification, threat status, and evolutionary distinctiveness of all extant species. RESULTS: In contrast to other terrestrial vertebrates and their own diversity in the fossil record, the recent extant lineages of turtles and crocodilians have not experienced any global mass extinctions or lineage-wide shifts in diversification rate or body-size evolution over time. We predict threat statuses for 114 as-yet unassessed or data-deficient species and identify a concentration of threatened turtles and crocodilians in South and Southeast Asia, western Africa, and the eastern Amazon. We find that unlike other terrestrial vertebrate groups, extinction risk increases with evolutionary distinctiveness: a disproportionate amount of phylogenetic diversity is concentrated in evolutionarily isolated, at-risk taxa, particularly those with small geographic ranges. Our findings highlight the important role of geographic determinants of extinction risk, particularly those resulting from anthropogenic habitat-disturbance, which affect species across body sizes and ecologies. CONCLUSIONS: Extant turtles and crocodilians maintain unique, conserved morphologies which make them globally recognizable. Many species are threatened due to exploitation and global change. We use taxonomically complete, dated molecular phylogenies and various approaches to produce a comprehensive assessment of threat status and evolutionary distinctiveness of both groups. Neither group exhibits significant overall shifts in diversification rate or body-size evolution, or any signature of global mass extinctions in recent, extant lineages. However, the most evolutionarily distinct species tend to be the most threatened, and species richness and extinction risk are centered in areas of high anthropogenic disturbance, particularly South and Southeast Asia. Range size is the strongest predictor of threat, and a disproportionate amount of evolutionary diversity is at risk of imminent extinction.


Assuntos
Jacarés e Crocodilos/classificação , Biodiversidade , Extinção Biológica , Geografia , Filogenia , Tartarugas/classificação , África Ocidental , Animais
15.
PLoS One ; 15(7): e0222251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726310

RESUMO

Sea level is expected to rise 44 to 74 cm by the year 2100, which may have critical, previously un-investigated implications for sea turtle nesting habitat on Bioko Island, Equatorial Guinea. This study investigates how nesting habitat will likely be lost and altered with various increases in sea level, using global sea level rise (SLR) predictions from the Intergovernmental Panel on Climate Change. Beach profiling datasets from Bioko's five southern nesting beaches were used in GIS to create models to estimate habitat loss with predicted increases in sea level by years 2046-2065 and 2081-2100. The models indicate that an average of 62% of Bioko's current nesting habitat could be lost by 2046-2065 and 87% by the years 2081-2100. Our results show that different study beaches showed different levels of vulnerability to increases in SLR. In addition, on two beaches erosion and tall vegetation berms have been documented, causing green turtles to nest uncharacteristically in front of the vegetation line. We also report that development plans are currently underway on the beach least susceptible to future increases in sea level, highlighting how anthropogenic encroachment combined with SLR can be particularly detrimental to nesting turtle populations. Identified habitat sensitivities to SLR will be used to inform the government of Equatorial Guinea to consider the vulnerability of their resident turtle populations and projected climate change implications when planning for future development. To our knowledge this is the first study to predict the impacts of SLR on a sea turtle nesting habitat in Africa.


Assuntos
Comportamento de Nidação/fisiologia , Elevação do Nível do Mar , Tartarugas/fisiologia , Animais , Ecossistema , Guiné Equatorial , Ilhas , Análise Espacial
16.
J Vis Exp ; (159)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32538918

RESUMO

The analysis of environmental DNA (eDNA) has become a widely used approach to problem solving in species management. The detection of cryptic species including invasive and (or) species at risk is the goal, typically accomplished by testing water and sediment for the presence of characteristic DNA signatures. Reliable and efficient procedures for the capture of eDNA are required, especially those that can be performed easily in the field by personnel with limited training and citizen scientists. The capture of eDNA using membrane filtration is widely used currently. This approach has inherent issues that include the choice of filter material and porosity, filter fouling, and time required on site for the process to be performed. Flocculation offers an alternative that can be easily implemented and applied to sampling regimes that strive to cover broad territories in limited time.


Assuntos
DNA Ambiental/química , Monitoramento Ambiental/métodos , Floculação/efeitos dos fármacos , Animais , Tartarugas
17.
Environ Pollut ; 265(Pt B): 114918, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32544788

RESUMO

In the last decade many studies have described the ingestion of plastic in marine animals. While most studies were dedicated to understanding the pre-ingestion processes involving decision-making foraging choices based on visual and olfactory cues of animals, our knowledge in the post-ingestion consequences remains limited. Here we proposed a theoretical complementary view of post-ingestion consequences, attempting to connect plastic ingestion with plastic-induced satiety. We analyzed data of plastic ingestion and dietary information of 223 immature green turtles (Chelonia mydas) from tropical Brazilian reefs in order to understand the impacts of plastic ingestion on foraging behavior. Generalized linear mixing models and permutational analysis of variance suggested that plastic accumulations in esophagus, stomach and intestine differed in their impact on green turtle's food intake. At the initial stages of plastic ingestion, where the plastic still in the stomach, an increase in food intake was observed. The accumulation of plastic in the gastrointestinal tract can reduce food intake likely leading to plastic-induced satiety. Our results also suggest that higher amounts of plastics in the gastrointestinal tract may led to underweight and emaciated turtles. We hope that adopting and refining our proposed framework will help to clarify the post-ingestion consequences of plastic ingestion in wildlife.


Assuntos
Plásticos , Tartarugas , Animais , Brasil , Ingestão de Alimentos , Conteúdo Gastrointestinal
18.
PLoS One ; 15(6): e0233483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492031

RESUMO

The newly discovered plattenkalk (platy limestone) locality of Wattendorf, southern Germany, has yielded a diverse fauna and flora dated to the base of the late Kimmeridgian, Late Jurassic. We here describe three fossil turtle specimens that were recovered during systematic excavations of a distinct, 15 cm thick package of plattenkalks by the Naturkunde-Museum Bamberg. The first specimen is a large shell of Achelonia formosa, a taxon that is based on material from the late Kimmeridgian of Cerin, France. The new specimen suggests synonymy with Enaliochelys chelonia from the late Kimmeridgian of the United Kingdom. The second is a near-complete skeleton of the enigmatic Tropidemys seebachi, which was previously known only from the late Kimmeridgian of Hannover, northern Germany. The third specimen is a partial skeleton of Eurysternum wagleri, which had previously been known only from the early Tithonian of the Solnhofen region, southern Germany. In addition to new anatomical insights, the new material provides further evidence for spatial links during the late Kimmeridgian between northern and southern Germany, France, and the United Kingdom and temporal link from the late Kimmeridgian to the early Tithonian. The prevalence of partial, though articulated specimens is suggestive of predation by an unknown large marine reptile.


Assuntos
Fósseis , Tartarugas , Animais , Fósseis/anatomia & histologia , Fósseis/história , Fenômenos Geológicos , Alemanha , História Antiga , Paleontologia , Filogeografia , Especificidade da Espécie , Tartarugas/anatomia & histologia , Tartarugas/classificação
19.
PLoS One ; 15(6): e0234805, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555669

RESUMO

The acute phase response is a highly conserved reaction to infection, inflammation, trauma, stress, and neoplasia. Acute phase assays are useful for wildlife health assessment, however, they are infrequently utilized in reptiles. This study evaluated erythrocyte sedimentation rate (ESR) in eastern (Terrapene carolina carolina) and ornate box turtles (Terrapene ornata ornata) and hemoglobin-binding protein (HBP) in T. ornata. Erythrocyte sedimentation rate in 90 T. carolina and 105 T. ornata was negatively associated with packed cell volume and was greater in unhealthy turtles (p < 0.05). Female T. ornata had higher ESR values than males (p < 0.05). Measurement of ESR with a microhematocrit tube proportionally overestimated values from a commercial kit (Winpette), though both methods may retain utility with separate reference intervals. Hemoglobin-binding protein concentration in 184 T. ornata was significantly increased in adults and unhealthy turtles (p < 0.05). Erythrocyte sedimentation rate values were similar between seasons and populations, and HBP values were consistent between years, indicating that these analytes may have more stable baseline values than traditional health metrics in reptiles. This study demonstrates that ESR and HBP are promising diagnostics for health assessment in wild box turtles. Incorporating these tests into wild herptile health assessment protocols may support conservation efforts and improve ecosystem health monitoring.


Assuntos
Hemoglobinas/metabolismo , Tartarugas , Animais , Sedimentação Sanguínea , Humanos
20.
PLoS One ; 15(6): e0228524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497041

RESUMO

Nester abundance is a key measure of the performance of the world's largest green turtle rookery at Raine Island, Australia, and has been estimated by mark-resight counts since 1984. Nesters are first marked by painting their carapace with a longitudinal white stripe. Painted and unpainted turtles are then counted by a surface observer on a small boat in waters adjacent to the reef. Unmanned aerial vehicles (UAV) and underwater video may provide more cost-effective and less biased alternatives to this approach, but estimates must be comparable with historical estimates. Here we compare and evaluate the three methods. We found comparatively little variation in resighting probabilities between consecutive days of sampling or time of day, which supports an underlying assumption of the method (i.e. demographic closure during sampling). This lack of bias in the location availability for detection of painted versus unpainted turtles and further supported by a parallel satellite tracking study of 40 turtles at Raine Island. Our results demonstrated that surface observers consistently reported higher proportions of marked turtles than either the UAV or underwater video method. This in turn yielded higher population estimates with UAV or underwater video compared to the historical surface observer method, which suggested correction factors of 1.53 and 1.73 respectively. We attributed this to observer search error because a white marked turtle is easier to spot than the non-marked turtle. In contrast, the UAV and underwater video methods allowed subsequent frame-by-frame review, thus reducing observer search error. UAVs were the most efficient in terms of survey time, personnel commitment and weather tolerance compared to the other methods. However, underwater video may also be a useful alternative for in-water mark-resight surveys of turtles.


Assuntos
Monitoramento Ambiental/instrumentação , Ilhas , Comportamento de Nidação , Tartarugas , Animais , Automação , Feminino , Imersão , Densidade Demográfica , Queensland , Gravação em Vídeo
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