Survey of parasites in sea turtles rescued off the coast of Santa Catarina and Paraná, Brazil (2020-2022) and their relationship with marine pollution.

The identification of parasite fauna can contribute to the assessment of the health status of sea turtles, and thus make it possible to develop effective management and treatment strategies aimed at conserving these animals. The present study aimed to investigate the parasite fauna in sea turtles rescued in six sections of the coast of Santa Catarina and Paraná (Brazil) from January 2020 to December 2022 through the recording of exam reports available in the Information System of Aquatic Biota Monitoring. In total, records of 334 sea turtles were analyzed during this period, of which 219 (65.6 %) were infected with at least one parasite. Chelonia mydas was the most frequent species with 86.5 % of rescues and presented the highest species richness. At least 43 species belonging to 36 different genera have been recorded parasitizing sea turtles. The most common helminths were Cricocephalus albus, Metacetabulum invaginatum, Pronocephalus obliquus, with 12.3 %, 8.7 % and 8.4 %, respectively, while protozoa of the genus Entamoeba were the most prevalent in the turtles analyzed (8.1 %). An interesting finding was the unprecedented finding of Hymenolepis sp. eggs in faeces of some turtle species. The results showed that the parasite fauna was quite diverse, with several species known to be capable of harming the physical health and well-being of sea turtles. In view of this, it is necessary to adopt strategies for monitoring the health of the different rescued species with a view to conserving sea turtles in Brazilian territory.

Genomic scan of a healthcare-associated NDM-1-producing Citrobacter freundii ST18 isolated from a green sea turtle impacted by plastic pollution.

BACKGROUND: Carbapenemase-producing Citrobacter freundii has been reported as a leading cause of healthcare-associated infections. Particularly, C. freundii belonging to the sequence type (ST) 18 is considered to be an emerging nosocomial clone. OBJECTIVES: To report the genomic background and phylogenomic analysis of a multidrug-resistant NDM-1-producing C. freundii ST18 (strain CF135931) isolated from an endangered green sea turtle affected by plastic pollution in Brazil. METHODS: Genomic DNA was extracted and sequenced using the Illumina NextSeq platform. De novo assembly was performed by CLC Workbench, and in silico analysis accomplished by bioinformatics tools. For phylogenomic analysis, publicly available C. freundii (txid:546) genome assemblies were retrieved from the NCBI database. RESULTS: The genome size was calculated at 5 290 351 bp, comprising 5263 total genes, 4 rRNAs, 77 tRNAs, 11ncRNAs, and 176 pseudogenes. The strain belonged to C. freundii ST18, whereas resistome analysis predicted genes encoding resistance to ß-lactams (blaNDM-1, blaOXA-1, blaCMY-117, and blaTEM-1C), aminoglycosides (aph(3'')-Ib, aadA16, aph(3')-VI, aac(6')-Ib-cr, and aph(6)-Id), quinolones (aac(6')-Ib-cr), macrolides (mph(A) and erm(B)), sulphonamides (sul1 and sul2), tetracyclines (tetA and tetD), and trimethoprim (dfrA27). The phylogenomic analysis revealed that CF135931 strain is closely related to international human-associated ST18 clones producing NDM-1. CONCLUSION: Genomic surveillance efforts are necessary for robust monitoring of the emergence of drug-resistant strains and WHO critical priority pathogens within a One Health framework. In this regard, this draft genome and associated data can improve understanding of dissemination dynamics of nosocomial clones of carbapenemase-producing C. freundii beyond hospital walls. In fact, the emergence of NDM-1-producing C. freundii of global ST18 in wildlife deserves considerable attention.

The use of an alimentary index to assess anthropogenic debris on green turtles (Chelonia mydas).

Studies on novel methodologies addressed to quantification of anthropogenic marine debris (AMD) types ingested by green turtles (Chelonia mydas) is not common in the scientific literature. To fill this gap, we used the alimentary index (IAi) to quantify and classify AMD ingested by green turtles stranded in the Potiguar Basin, northeastern Brazil. We classified 295 green turtles as juveniles (JUV-I (n = 190) and JUV-II (n = 58)) and adults (ADU (n = 47)). We collected gut contents during necropsy and analyzed them using the IAi. The IAi values were categorized as main (IAi ≥ 0.5), secondary (0.25 ≤ IAi < 0.5), and accessory (IAi < 0.25). The results revealed that transparent soft plastic was an accessory item for the three size groups and the second most frequent item (IAi = 0.23) for JUV-I. Our study brings insights into the application of the IAi to evaluate the amount and types of AMD ingested by green turtles.

A Pilot Study of Mercury Distribution in the Carapace of Four Species of Sea Turtles from Northeastern Brazil.

Scutes present very complex morphologies with different growth rates at different areas of the carapace that can change the accumulation process of essential and non-essential metals. To infer the effects of morphology and growth on Hg concentrations in scutes, we mapped them in the carapace of one individual of four species of sea turtles sampled along the Brazilian coast. The results showed that Hg concentrations were higher in the vertebral scutes of Chelonia mydas and Eretmochelys imbricata suggesting variation in growth rates of different carapace areas since the vertebral area is the first to develop prior to costal areas. Caretta caretta and Lepidochelys olivacea did not show differences between carapace areas. The preliminary data from this pilot study indicate that vertebral scutes may be suitable for monitoring Hg in C. mydas and E. imbricata, since they reflect longer exposure period. A species-to-species comparison of Hg concentrations is not possible due to the small number of sampled individuals, nevertheless, E. imbricata showed remarkably lower Hg concentrations compared to the other three species. Further studies are required for all four species, with a larger number of individuals, preferentially of varying life stages, due to the unknown effects of different diets, Hg exposure, and migration histories.

Predation Rate on Olive Riley Sea Turtle (Lepidochelys olivacea) Nests with Solitary Nesting Activity from 2008 to 2021 at Corozalito, Costa Rica.

In Corozalito beach, Costa Rica, Olive Ridley turtles (Lepidochelys olivacea) nest both solitarily and in arribadas. The predation of solitary nests was monitored from 2008 to 2021, recording date, time, sector of the beach, zone, status of nest (predated or partially predated) and predator when possible. We recorded 4450 predated nests in total (N = 30,148 nesting events); predation rates showed a fluctuating trend, with recent percentages reaching up to 30%, with four distinctive dips in 2010, 2014, 2016 and 2017. The spatial distribution of predated nests along the beach showed significant differences among the sectors regardless of the seasons (Friedman test, chi-squared = 14.778, df = 2, p-value = 0.000), with most predated nests (47.62%) occurring in the northern sectors of the beach. Predators were identified by their tracks and/or direct observations (N = 896, 24.08%). The most conspicuous predators identified were raccoons (55.69%) and black vultures (22.77%). As seen in Corozalito, predation rates have increased in recent years despite established conservation efforts. A comprehensive assessment of all threats towards the overall hatching success for clutches is needed, considering predation during mass nesting events, poaching and beach erosion, among other factors, to fully understand the nesting dynamics occurring in this beach.

Hawksbill Sea Turtle (Eretmochelys imbricata) Blood and Eggs Organochlorine Pesticides Concentrations and Embryonic Development in a Nesting Area (Yucatan Peninsula, Mexico).

Environmental contaminants with chemical origins, such as organochlorine pesticides (OCPs) have major impacts on the health of marine animals, including sea turtles, due to the bioaccumulation of those substances by transference throughout the food chain. The effects of environmental pollution on the health of marine turtles are very important for management strategies and conservation. During recent decades, the south Gulf of Mexico and the Yucatan Peninsula have suffered from increasingly frequent disturbances from continental landmasses, river systems, urban wastewater runoff, port areas, tourism, industrial activities, pesticides from agricultural use, and other pollutants, such as metals, persistent organic pollutants (POPs) and hydrocarbons (from the oil industry activities), which contaminate water and sediments and worsen the environmental quality of the marine ecosystem in this region. In this study, we assessed the concentrations of OCPs in the blood and eggs of 60 hawksbill turtles (Eretmochelys imbricata) nesting at the Punta Xen turtle camp, and their effects on the nesting population's reproductive performance: specifically, maternal transfer and embryonic development were analyzed. Hematologic characteristics, including packed cell volume, white blood cell count, red blood cell count, and haemoglobin levels, and plasma chemistry values, including creatinine, blood urea nitrogen, uric acid, triglyceride, total cholesterol and glucose, were also measured. The general health of the turtles in this study, as well as their levels of urea, serum creatinine, glucose, uric, acid, cholesterol, and triglyceride, fell within normal ranges and was similar to other normal values, which could indicate the turtles' good energy levels and body conditions for nest-building activity, with all of the turtles able to successfully come ashore to nest. All the same, the obtained results also indicate that OCPs affect the nesting and reproductive performance of the hawksbill turtles, as well as their fertility and the development of the population of eggs and reproductive performance, specifically in terms of maternal transference and embryonic development. There were significant differences in the concentrations of OCPs (ΣHCHs and ΣDienes) between maternal blood and eggs, indicating that these chemicals are transferred from nesting females to eggs and, ultimately, to hatchlings. OCPs may, therefore, have an effect on the health and reproductive performance of hawksbill turtles, both in terms of their fertility and egg development. Conservation strategies need to be species-specific, due to differences in feeding, and address the reasons for any decline, focusing on regional assessments. Thus, accurate and comparable monitoring data are necessary, which requires the standardization of monitoring protocols.

Life after death? Exploring biochemical and molecular changes following organismal death in green turtles, Chelonia mydas (Linnaeus, 1758).

Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.

First report of Caryospora sp. infection in free-living green turtles (Chelonia mydas) in Northeastern Brazil.

Infection by Caryospora cheloniae has been reported to be responsible for green turtle strandings with high morbidity and mortality rates worldwide. Although studies have already shown the pathogenesis of these infections, many aspects of this protozoan are still poorly understood, including their life cycle and infection dynamics in free-living sea turtle populations. Due to the lack of information about the infection by this protozoan in sea turtles in Northeastern Brazil, our study aims to describe Caryospora sp. infection and its pathological findings in free-living Chelonia mydas found on the north coast of the Bahia state. Between 2018 and 2019, 64 specimens of green turtles were necropsied in partnership with Fundação Projeto Tamar; among these, 10 (1.56%) had oocysts morphologically compatible with Caryospora cheloniae in the evaluation of fecal samples and histopathological examination of intestinal samples. The infected animals were juvenile green turtles that were found stranded on the beaches of the north coast of Bahia. The pathological findings were restricted to the lower gastrointestinal tract, with different presentations and intensities. About 70% of the animals with coccidial infection exhibited erosive and ulcerative fibrinous enteritis. This is the first report of coccidiosis in green turtles on the north coast of Bahia.

Bacterial and fungal pathogens in granulomatous lesions of Chelonia mydas in a significant foraging ground off southern Brazil.

The green sea turtle Chelonia mydas inhabit near-shore areas exposed to threatening anthropogenic activities. The granulomatous lesions in these animals may indicate infectious diseases that can be associated with environmental contamination and hazards to human health. This study aimed to characterize the granulomatous inflammation associated with bacterial and fungal infection in C. mydas off Paraná state. From September 2015 to February 2019, systematic monitoring was performed by the Santos Basin Beach Monitoring Project for sea turtles'carcasses recovery, necropsy, and cause of death diagnosis. The tissue samples were fixed in buffered formalin 10% for histochemical analysis and frozen for molecular analysis to fungi detection (Internal Transcribed Spacer region of the nuclear rDNA) and bacteria detection (16S ribosomal gene). From a total of 270 C. mydas, granulomatous lesions were observed in different organs of 63 (23.3%) individuals. The histological analysis indicated lesions in 94 organs, affecting most respiratory and digestive systems. Bacteria were identified in 25 animals, including an acid-fast bacteria detected in one animal, and fungi in 24 C. mydas. The fungi species included the genus Candida (Candida zeylanoides, n = 3), Yarrowia (Yarrowia lipolytica, n = 9; Yarrowia deformans, n = 5; and Yarrowia divulgata, n = 1), and Cladosporium anthropophilum (n = 1). No species of bacteria was identified by molecular testing. All fungi species identified are saprobic, some are important to food and medical industries, but are also pathogens of humans and other animals. Therefore, long-term monitoring of these pathogens and the C. mydas health may indicate changes in environmental quality, possible zoonotic diseases, and their effects.

Rehabilitation of Marine Turtles and Welfare Improvement by Application of Environmental Enrichment Strategies.

Sea turtles perform various ecological services in several marine environments and are considered architects of the marine landscape. At present, they are endangered species due to anthropogenic threats, pollution and degradation of marine habitats. These impacts make it urgent to increase protection and conservation efforts. Protective actions include the rescue and rehabilitation of injured individuals as a result of their interactions with humans and other threats. Environmental enrichment (EE) is a series of techniques and methods aimed to improve the welfare of animals in captivity and/or under rehabilitation. It uses external stimuli to enhance their psychological and physiological wellbeing to promote natural abilities and behaviors. These may increase the survival chances of rehabilitated animals upon release in the wild. This review presents data of studies where EE has been applied during the rehabilitation processes of different species of sea turtles, and its effect on welfare improvement during captivity/rehabilitation and on survival after release into nature. Technologies such as satellite tags are an important means to determine rehabilitation success and survival of injured individuals from endangered species after release into the wild, as they allow tracking and monitoring of such individuals, and determine their location in areas used by their natural populations for feeding or breeding.

Size-Mediated Sea Turtle Behavioral Responses at Artificial Habitats in the Northern Gulf of Mexico.

Our understanding of size-specific sea turtle behavior has lagged due to methodological limitations. However, stereo-video cameras (SVC) are an in-water approach that can link body-size and allow for relatively undisturbed behavioral observations. In this study, we conducted SVC dive surveys at local artificial reefs, piers, and jetties in the northern Gulf of Mexico (nGOM) from May 2019 to August 2021. Using SVCs, we measured sea turtle straight carapace length, documented behaviors, and quantified wariness by assessing minimum approach distance (MAD). In green sea turtles (Chelonia mydas), the observed MAD ranged from 0.72 to 5.99 m (mean 2.10 m ± 1.10 standard deviation (SD), n = 73). For loggerhead sea turtles (Caretta caretta), the MAD ranged between 0.93 and 3.80 m (mean 2.12 m ± 0.99 SD, n = 16). Kemp's ridley sea turtles (Lepidochelys kempii) were similar to loggerheads, and MAD ranged from 0.78 to 3.63 m (mean 2.35 m ± 0.99 SD, n = 8). We then evaluated what biological factors could impact the MAD observed by species, but we excluded Kemp's ridleys as the sample size was small. Using a linear mixed model and model selection based on AICc, the top ranked model for both green and loggerhead sea turtles included SCL as the most important factor influencing MAD. MAD did not vary with habitat type for either species. Our results showed that larger individuals, regardless of species, have a greater wariness response, becoming startled at greater distances than smaller individuals. The findings of our study support the use of SVC as an accessible, non-invasive tool to conduct ecologically relevant in-water surveys of sea turtles to link behavioral observations to body size.

Reproductive and ecological similarity between Caretta caretta (Linnaeus, 1758) and Eretmochelys imbricata (Linnaeus, 1766) in southern Bahia (Brazil) / Semelhança reprodutiva e ecológica entre Caretta caretta (Linnaeus, 1758) e Eretmochelys imbricata (Linnaeus, 1766) no sul da Bahia (Brasil)

This study evaluates the reproductive and ecological similarity between loggerhead sea turtle (Caretta caretta) and Hawksbill sea turtle (Eretmochelys imbricata) two species of sea turtles on the southern coast of Bahia (Brazil) during two breeding seasons (October to April 2013 to 2015). The study covers a 10-km area composed of three beaches, Pompilho, Itacarezinho and Patizeiro beach, which are 5, 3, and 2 km long, respectively. Daily field surveys were performed for 102 days to assess patterns between the studied species, using the non-metric multidimensional scaling order and the Spearman correlation analysis to obtain the oviposition pattern of the two species. Moreover, Kruskall-Wallys tests were performed to review the differences in the number of hatchlings on the three beaches. The NMDS proved the species are very similar from an ecological perspective since as there were three clear groupings in terms of the number of hatchlings on the three beaches. With reference to the number of nests, a negative correlation was observed in the two species. Regarding the hatching activity of both species on the three beaches studied, a larger amount of C. caretta and E. imbricata hatchlings was found on Pompilho beach, followed by Patizeiro and Itacarézinho. These findings influence management strategies to reduce anthropogenic impact and contribute to the conservation of these two endangered sea turtle species.

Este estudo avalia a semelhança reprodutiva e ecológica entre a tartaruga cabeçuda (Caretta caretta) e a tartaruga-de-pente (Eretmochelys imbricata) duas espécies de tartarugas marinhas no litoral sul da Bahia (Brasil) durante duas estações reprodutivas (outubro a abril de 2013 a 2015) . O estudo abrange uma área de 10 km composta por três praias, Pompilho, Itacarezinho e praia do Patizeiro, com 5, 3 e 2 km de extensão, respectivamente. Foram realizados levantamentos diários de campo durante 102 dias para avaliar padrões entre as espécies estudadas, utilizando a ordem de escala multidimensional não métrica e a análise de correlação de Spearman para obter o padrão de oviposição das duas espécies. Além disso, testes de Kruskall-Wallys foram realizados para revisar as diferenças no número de filhotes nas três praias. O NMDS provou que as espécies são muito semelhantes do ponto de vista ecológico, pois havia três agrupamentos claros em termos do número de filhotes nas três praias. Com relação ao número de ninhos, foi observada correlação negativa nas duas espécies. Em relação à atividade de eclosão de ambas as espécies nas três praias estudadas, uma maior quantidade de filhotes de C. caretta e E. imbricata foi encontrada na praia do Pompilho, seguida de Patizeiro e Itacarézinho. Esses achados influenciam as estratégias de manejo para reduzir o impacto antropogênico e contribuir para a conservação dessas duas espécies de tartarugas marinhas ameaçadas de extinção.

Relación entre la temperatura de incubación y la asimetría del carapacho de neonatos de Lepidochelys olivacea incubados en el Área de Usos Múltiples Hawaii (AUMH), Santa Rosa, Guatemala / Relationship between incubation temperature and carapace asymmetry of neonates of Lepidochelys olivacea incubated in the Area of Multiple Use Hawaii (AUMH), Santa Rosa, Guatemala

Los embriones de tortugas marinas son susceptibles a perturbaciones ambientales, las cuales se traducen en anomalías en su fenotipo. Uno de los principales parámetros para la medición de estas perturbaciones es la asimetría en los carapachos (caparazones), que puede ser obtenida a través del Índice de Inestabilidad de Desarrollo (DIx, por sus siglas en inglés). La temperatura juega un rol importante, influenciando no solo en la futura supervivencia de los neonatos en temperaturas extremas (altas o bajas), sino en atributos específicos, tales como la determinación del sexo, o incluso puede ser la causa del incremento en el número de apéndices dérmicos (escudos) sobre la parte dorsal del carapacho. Este estudio evaluó la relación entre la temperatura de incubación con la asimetría de carapacho de los neonatos de Lepidochelys olivacea incubados en condiciones relocalizadas en el tortugario del Área de Usos Múltiples Hawaii en Santa Rosa, Guatemala. Para lograrlo, se replicaron las condiciones de anidación seleccionadas por las hembras anidadoras en nidos relocalizados, utilizando dispositivos termosensitivos para la toma de la temperatura durante el período de incubación. A través del cálculo del DIx en 210 neonatos, y mediante las pruebas de correlación de Kendall y Jockheere-Terpstra, se obtuvo que en valores de temperaturas extremas tanto altas (Kendall tau = .23, p < .001; JT = 2,891, p < .001), como bajas (Kendall tau u= -.21, p < .001; JT = 5,005, p < .001), así como en altos rangos de variación durante el período de desarrollo embrionario (Kendall tau = .23, p < .001; JT = 6,619, p < .05), los neonatos presentan una mayor asimetría.

Sea turtle embryos are susceptible to environmental disturbances, which result in abnormalities in their phenotype. One of the main parameters for measuring these disturbances is the asymmetry in the carapaces, which can be obtained through the Developmental Instability Index (DIx). Temperature plays an important role, influencing not only the future survival of hatchlings in extreme temperatures (high or low), but also specific attributes, such as sex determination, or it can even be the cause of the increase in the number of dermal appendages (shields) on the dorsal part of the carapace. This aimed to evaluate the relationship between incubation temperature and carapace asymmetry of Lepidochelys olivacea hatchlings incubated in relocated conditions in the Hawaii Multiple Use Area turtle rookery in Santa Rosa, Guatemala. To achieve this, the nesting conditions selected by the nesting females were replicated in relocated nests, using thermosensitive devices to measure the temperature during the incubation period. rough the calculation of DIx in 210 hatchlings, and using Kendall and Jockheere-Terpstra correlation tests, it was obtained that hatchlings present greater asymmetry in values of extreme temperatures, for both, high (Kendall: p<.05, tau = .232 ; JT p<.05, JT=2891) and low (Kendall: p<.05, tau= -.211 ; JT p<.05, JT=5005); as well as in high ranges of variation (Kendall: p<.05, tau= .231 ; JT p<.05, JT=6619), during the embryonic development period

Plastic ingestion by juvenile green turtles (Chelonia mydas) off the coast of Southern Brazil.

Five of the seven extant sea turtle species in the world forage on the coast of Southern Brazil at least in some stage of their life cycle. The green turtle Chelonia mydas frequently strands on beaches of Rio Grande do Sul State. The species is currently classified as vulnerable to extinction in the region, and pollution by marine debris is one of the most conspicuous threats to its conservation. In this study, we quantified and characterized plastic ingestion by juvenile green turtles in waters off the southern Brazilian coast between 2013 and 2016. We analysed the gastrointestinal content of 17 beached carcasses and registered debris ingestion in 15 individuals (88%). On average, each green turtle ingested 38.4 ± 88.5 plastic fragments. White and transparent plastic bags and plastic sheets were predominant. Our results indicate a high interaction between juvenile green turtles and marine debris off the coast of Southern Brazil.

Plesiochorus Cymbiformis (Rudolphi, 1819) Looss, 1901 (Digenea: Gorgoderidae) in Olive Ridley Sea Turtles Lepidochelys Olivacea (Eschscholtz, 1829) (Testudines: Chelonidae) from The Brazilian Coast: New Geographic Occurrence and Associated Injuries.

The present study reports the first occurrence of Plesiochorus cymbiformis (Digenea: Gorgoderidae), in two Olive Ridley Sea turtles Lepidochelys olivacea (Testudines: Chelonidae), from the states of São Paulo and Sergipe in Brazilian coast. Concerning the Neotropical region, P. cymbiformis has been previously reported in green sea turtles (Chelonia mydas) from Panama and Brazil, in loggerhead sea turtles (Caretta caretta) from Brazil, in hawksbill sea turtles (Eretmochelys imbricata) from Puerto Rico, and in Olive Ridley Sea turtles only in Costa Rica. Lesions resulting from the presence of parasites in the hosts' urinary bladders are also presented. This is the second report on endoparasites in Olive Ridley sea turtles from Brazil.

Isolation and characterization of the aerobic bacterial microbiota of the esophagus and its probable association with obstructive caseous lesions in green turtles (Chelonia mydas) / Isolamento e caracterização da microbiota bacteriana aeróbia do esôfago e sua provável associação com lesões caseosas obstrutivas em tartarugas-verdes (Chelonia mydas)

Caseous lesions in the esophagus of green turtles (Chelonia mydas) from the coast of Brazil have been described as obstructive lesions and can lead to the death of these animals. However, their etiology remains unclear. The aim of this study was to isolate and characterize the aerobic bacterial microbiota of the esophagus of green turtles (C. mydas) from the Brazilian coast and to verify its possible participation in the etiology of caseous lesions. For this, 42 animals were used, 33 alive and healthy and 9 naturally dead that had esophageal lesions confirmed by necropsy, from Anchieta and Piúma beaches, Espírito Santo. Microbiological tests and morphological evaluation of the esophagus were performed. We isolated 14 different bacterial agents from healthy animal samples, with the prevalence of Pseudomonas aeruginosa being (36.36%), Staphylococcus aureus (33.33%), Aeromonas hydrophila (27.27%), and Vibrio alginolyticus (24.24%). In dead animals, only three distinct agents were isolated: S. aureus (50.00%), A. hydrophila (25.00%), and V. alginolyticus (25.00%). Morphological evaluation revealed a predominance of the lesions at the gastroesophageal junction, with multifocal-to-coalescent distribution, discrete intensity, and absence of obstruction. Ulcerations and caseous exudates, inflammatory infiltrates, parasitic eggs, and giant foreign body cells were also observed as well as bacterial lumps and glandular alterations, such as necrosis, adenitis, and fragments of adult parasites. There was a positive correlation between bacterial lumps and microbiological culture and a negative correlation between bacterial lumps and microbiological culture with parasites. Thus, it was noted that the esophageal aerobic microbiota of C. mydas was predominantly composed of Gram-negative bacteria such as P. aeruginosa, A. hydrophila, and V. alginolyticus, in addition to several enterobacteria and Gram-positive bacteria, such as S. aureus. These agents are opportunists and may be involved in the etiology of caseous esophagitis in association with other pathogens as co-factors working in association or, even in a secondary way.(AU)

A ocorrência de lesão caseosa no esôfago de tartarugas-verdes (Chelonia mydas) da costa do Brasil tem sido descrita como de caráter obstrutivo e pode causar a morte dos animais. No entanto, sua etiologia permanece pouco esclarecida. Objetivou-se isolar e caracterizar a microbiota aeróbica esofágica das tartarugas-verdes (C. mydas) da costa brasileira e verificar sua possível participação na etiologia das lesões caseosas. Foram utilizados 42 animais, 33 vivos e hígidos e nove mortos naturalmente que apresentavam lesão esofágica confirmada pela necropsia, provenientes de Anchieta e Piúma, Espírito Santo, nos quais foram feitos testes microbiológicos e avaliação morfológica do esôfago. Foram isolados 14 agentes bacterianos diferentes nas amostras de animais saudáveis, com prevalência de Pseudomonas aeruginosa (36,36%), Staphylococcus aureus (33,33%), Aeromonas hydrophila (27,27%) e Vibrio alginolyticus (24,24%). Nos animais mortos, foram isolados apenas três agentes distintos: S. aureus (50,00%), A. hydrophila (25,00%) e V. alginolyticus (25,00%). A avaliação morfológica revelou predominância da lesão em junção gastroesofágica, com distribuição multifocal a coalescente, intensidade discreta e ausência de obstrução. Observou-se ainda ulceração e exsudato caseoso, infiltrado inflamatório, ovos de parasitos e células gigantes do tipo corpo estranho, além de grumos bacterianos e de alterações glandulares, como necrose, adenite e fragmentos de parasitos adultos. Houve correlação positiva dos grumos bacterianos com cultivo microbiológico e negativa dos grumos bacterianos e cultivo microbiológico com parasitos. Assim, nota-se que a microbiota esofágica aeróbica de C. mydas é constituída predominantemente por bactérias Gram-negativas como P. aeruginosa, A. hydrophila e V. alginolyticus, além de diversas enterobatérias e por Gram-positivas, como S. aureus. Esses agentes são oportunistas e podem estar envolvidos na etiologia da esofagite caseosa em associação a outros patógenos como co-fatores agindo em associação, ou mesmo, por via de infecção secundária.(AU)

Isolation and characterization of the aerobic bacterial microbiota of the esophagus and its probable association with obstructive caseous lesions in green turtles (Chelonia mydas) / Isolamento e caracterização da microbiota bacteriana aeróbia do esôfago e sua provável associação com lesões caseosas obstrutivas em tartarugas-verdes (Chelonia mydas)

Caseous lesions in the esophagus of green turtles (Chelonia mydas) from the coast of Brazil have been described as obstructive lesions and can lead to the death of these animals. However, their etiology remains unclear. The aim of this study was to isolate and characterize the aerobic bacterial microbiota of the esophagus of green turtles (C. mydas) from the Brazilian coast and to verify its possible participation in the etiology of caseous lesions. For this, 42 animals were used, 33 alive and healthy and 9 naturally dead that had esophageal lesions confirmed by necropsy, from Anchieta and Piúma beaches, Espírito Santo. Microbiological tests and morphological evaluation of the esophagus were performed. We isolated 14 different bacterial agents from healthy animal samples, with the prevalence of Pseudomonas aeruginosa being (36.36%), Staphylococcus aureus (33.33%), Aeromonas hydrophila (27.27%), and Vibrio alginolyticus (24.24%). In dead animals, only three distinct agents were isolated: S. aureus (50.00%), A. hydrophila (25.00%), and V. alginolyticus (25.00%). Morphological evaluation revealed a predominance of the lesions at the gastroesophageal junction, with multifocal-to-coalescent distribution, discrete intensity, and absence of obstruction. Ulcerations and caseous exudates, inflammatory infiltrates, parasitic eggs, and giant foreign body cells were also observed as well as bacterial lumps and glandular alterations, such as necrosis, adenitis, and fragments of adult parasites. There was a positive correlation between bacterial lumps and microbiological culture and a negative correlation between bacterial lumps and microbiological culture with parasites. Thus, it was noted that the esophageal aerobic microbiota of C. mydas was predominantly composed of Gram-negative bacteria such as P. aeruginosa, A. hydrophila, and V. alginolyticus, in addition to several enterobacteria and Gram-positive bacteria, such as S. aureus. These agents are opportunists and may be involved in the etiology of caseous esophagitis in association with other pathogens as co-factors working in association or, even in a secondary way.(AU)

A ocorrência de lesão caseosa no esôfago de tartarugas-verdes (Chelonia mydas) da costa do Brasil tem sido descrita como de caráter obstrutivo e pode causar a morte dos animais. No entanto, sua etiologia permanece pouco esclarecida. Objetivou-se isolar e caracterizar a microbiota aeróbica esofágica das tartarugas-verdes (C. mydas) da costa brasileira e verificar sua possível participação na etiologia das lesões caseosas. Foram utilizados 42 animais, 33 vivos e hígidos e nove mortos naturalmente que apresentavam lesão esofágica confirmada pela necropsia, provenientes de Anchieta e Piúma, Espírito Santo, nos quais foram feitos testes microbiológicos e avaliação morfológica do esôfago. Foram isolados 14 agentes bacterianos diferentes nas amostras de animais saudáveis, com prevalência de Pseudomonas aeruginosa (36,36%), Staphylococcus aureus (33,33%), Aeromonas hydrophila (27,27%) e Vibrio alginolyticus (24,24%). Nos animais mortos, foram isolados apenas três agentes distintos: S. aureus (50,00%), A. hydrophila (25,00%) e V. alginolyticus (25,00%). A avaliação morfológica revelou predominância da lesão em junção gastroesofágica, com distribuição multifocal a coalescente, intensidade discreta e ausência de obstrução. Observou-se ainda ulceração e exsudato caseoso, infiltrado inflamatório, ovos de parasitos e células gigantes do tipo corpo estranho, além de grumos bacterianos e de alterações glandulares, como necrose, adenite e fragmentos de parasitos adultos. Houve correlação positiva dos grumos bacterianos com cultivo microbiológico e negativa dos grumos bacterianos e cultivo microbiológico com parasitos. Assim, nota-se que a microbiota esofágica aeróbica de C. mydas é constituída predominantemente por bactérias Gram-negativas como P. aeruginosa, A. hydrophila e V. alginolyticus, além de diversas enterobatérias e por Gram-positivas, como S. aureus. Esses agentes são oportunistas e podem estar envolvidos na etiologia da esofagite caseosa em associação a outros patógenos como co-fatores agindo em associação, ou mesmo, por via de infecção secundária.(AU)

Temperature-Dependent Sex Determination in Sea Turtles in the Context of Climate Change: Uncovering the Adaptive Significance.

The adaptive significance of temperature-dependent sex determination (TSD) in reptiles remains unknown decades after TSD was first identified in this group. Concurrently, there is growing concern about the effect that rising temperatures may have on species with TSD, potentially producing extremely biased sex ratios or offspring of only one sex. The current state-of the-art in TSD research on sea turtles is reviewed here and, against current paradigm, it is proposed that TSD provides an advantage under warming climates. By means of coadaptation between early survival and sex ratios, sea turtles are able to maintain populations. When offspring survival declines at high temperatures, the sex that increases future fecundity (females) is produced, increasing resilience to climate warming. TSD could have helped reptiles to survive mass extinctions in the past via this model. Flaws in research on sex determination in sea turtles are also identified and it is suggested that the development of new techniques will revolutionize the field.

Quantifying local ecological knowledge to model historical abundance of long-lived, heavily-exploited fauna.

Deriving robust historical population trends for long-lived species subject to human exploitation is challenging in scenarios where long-term scientific data are scarce or unavailable, as often occurs for species affected by small-scale fisheries and subsistence hunting. The importance of Local Ecological Knowledge (LEK) in data-poor scenarios is increasingly recognized in conservation, both in terms of uncovering historical trends and for engaging community stewardship of historic information. Building on previous work in marine historical ecology and local ecological knowledge, we propose a mixed socio-ecological framework to reliably document and quantify LEK to reconstruct historical population trends. Our method can be adapted by interdisciplinary teams to study various long-lived taxa with a history of human use. We demonstrate the validity of our approach by reconstructing long-term abundance data for the heavily-exploited East Pacific green turtle (Chelonia mydas) in Baja California, Mexico, which was driven to near extinction by a largely unregulated fishery from the early 1950s to the 1980s. No scientific baseline abundance data were available for this time-frame because recent biological surveys started in 1995 after all green turtle fisheries in the area were closed. To fill this data gap, we documented LEK among local fishers using ethnographic methods and obtained verified, qualitative data to understand the socio-environmental complexity of the green turtle fishery. We then established an iterative framework to synthesize and quantify LEK using generalized linear models (GLMs) and nonlinear regression (NLR) to generate a standardized, LEK-derived catch-per-unit-effort (CPUE) time-series. CPUE is an index of abundance that is compatible with contemporary scientific survey data. We confirmed the accuracy of LEK-derived CPUE estimates via comparisons with fisheries statistics available for 1962-1982. We then modeled LEK-derived abundance trends prior to 1995 using NLR. Our model established baseline abundance and described historical declines, revealing that the most critical (exponential) decline occurred between 1960 and 1980. This robust integration of LEK data with ecological science is of critical value for conservation and management, as it contributes to a holistic view of a species' historic and contemporary conservation status.

Pathological Findings in Leatherback Sea Turtles (Dermochelys coriacea) During an Unusual Mortality Event in São Paulo, Brazil, in 2016.

The leatherback sea turtle (LST; Dermochelys coriacea) is highly migratory and is primarily distributed throughout tropical and subtropical regions. The LST populations found in Brazil are critically endangered. An unusual mortality event occurred between August and November 2016 with 23 LSTs stranded along a 100 km coastal segment in Iguape, Ilha Comprida and Ilha do Cardoso in southern São Paulo state. This study investigated the pathological findings and most likely causes of death of 10 LSTs. Male (n = 9) and adult (n = 9) animals predominated. All but one animal was in good body condition and all were found dead. The most prevalent gross findings were suggestive of bycatch, namely cutaneous erosions, abrasions and/or lacerations around the neck and flippers (n = 9), generalized congestion (n = 8) and pulmonary oedema (n = 6). Other prevalent gross findings were: cutaneous epibiosis by Stomatolepas elegans (n = 7); ileocecal diverticulitis (n = 7); distal oesophagitis (n = 5); and fibrinous coelomitis (n = 5). Microscopically, the most prevalent findings were: hepatic melanomacrophage centre hypertrophy or hyperplasia (n = 9); interstitial pneumonia (n = 8); multisystemic congestion (n = 6); pulmonary oedema with or without aspirated material (n = 5); adrenal coccidiosis (n = 5) with variable multiorgan involvement; and multiorgan bacterial disease (n = 5). Five animals had food ingesta (cnidarians, crustaceans) in the oesophagus or stomach; only one had evident plastic foreign bodies. Asphyxia due to entanglement in nets was the most frequently identified cause of death (n = 8); a cause of death was not identified in two animals. Our findings provide evidence of the severe negative impact of entanglement in fishing nets in LSTs, raising concerns for conservation. These findings also contribute to knowledge of the pathology of LSTs in South American populations.