Photo-identification shows the spatio-temporal distribution of two sea turtle species in a Brazilian developmental foraging ground.

Sea turtles spend most of their life cycle in foraging grounds. Research in developmental habitats is crucial to understanding individual dynamics and to support conservation strategies. One approach to gather information in foraging grounds is the use of cost-effective and non-invasive techniques that allow public participation. The present study aimed to use photographic-identification (photo-ID) to investigate the spatio-temporal distribution of Chelonia mydas and Eretmochelys imbricata. Furthermore, we describe fibropapillomatosis occurrence. This work was carried out at subtropical rocky reefs of the Brazilian coast in Arraial do Cabo (22°57'S, 42°01'W), within a sustainable conservation unit. A total of 641 images were obtained through social media screening (n = 447), citizen science (n = 168), or intentional capture (n = 26) dated between 2006 and 2021. Additionally, 19 diving forms (between 2019 and 2021) were received from citizen scientists. All diving forms presented at least one turtle. Photo-ID identified 174 individuals of C. mydas, with 45 being resighted, while E. imbricata had 32 individuals, with 7 individuals resighted. The median interval between the first and last individual sighting was 1.7 years for C. mydas and 2.4 years for E. imbricata. Fibropapillomatosis was only observed in C. mydas, with a prevalence of 13.99% (20 of 143 individuals) and regression in 2 individuals (10.00%). Our results indicated that Arraial do Cabo is an important development area with individuals residing for at least 6 years. This study demonstrated that social media, along with photo-ID, can be useful to provide sea turtle estimates in a foraging ground using a non-invasive, low-cost method. Supplementary Information: The online version contains supplementary material available at 10.1007/s00227-023-04226-z.

A Preliminary Report of Plastic Ingestion by Hawksbill and Green Turtles in the Saudi Arabian Red Sea.

(1) Background: Plastic pollution is a major environmental concern confronting marine animals. Sea turtles are considered a bio-indicator of plastic pollution, but there is little information regarding plastic ingestion by turtles in the Red Sea. With large-scale development projects being built along the Saudi Arabian coast, it is important to have a baseline for plastic ingestion before construction is complete. (2) Methods: Ten deceased sea turtles (four hawksbill and six green turtles) were collected along the Saudi Arabian coastline. Necropsies were conducted, and the entire gastrointestinal tracts were extracted and the contents were passed through a 1 mm mesh sieve. (3) Results: We found that 40% of the turtles in this study had ingested plastics. Thread-like plastics were the most common plastic category, and multi-colored was the most prevalent color category. (4) Conclusions: Monitoring of the plastic ingestion by marine megafauna should be conducted as a long-term assessment of the developments' impacts. Additionally, conservation efforts should be focused on removing plastics (namely ghost nests and fishing lines) from the reefs and reducing the amount of plastic entering the sea.

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.

Intoxication par tortue de mer vue au Centre Hospitalier Universitaire Antanambao, Toliara, Madagascar / Poisoning by sea turtle at the Antanambao University Hospital, Toliara, Madagasca

Le chélonitoxisme est une intoxication collective par consommation de la chair, de la peau et des viscères de la tortue marine. Elle est peu fréquente. Notre objectif était de décrire l'aspect épidémio-clinique et thérapeutique de l'intoxication par tortue de mer. Méthodes : Il s'agit d'un rapport de cas effectué au Centre Hospitalier Universitaire (CHU) Antanambao Toliara, Madagascar après une intoxication collective dans la commune rurale de Soalara Sud, Toliara. Résultats : Nous avons colligé 70 patients qui ont ingéré une tortue adulte du genre Eretmochelys imbricata. Les signes cliniques étaient du type chélonitoxisme. Parmi les 70 cas, 8 patients ont été hospitalisés. L'âge des patients intoxiqués variait de 2 ans à 65 ans avec un âge moyen de 20 ± 14 ans. La tranche d'âge entre 10-20 ans était la plus touchée (44%). Les hommes représentaient 54% des patients avec un sex ratio de 1,18. Cinquante-huit pourcent ont eu leurs premiers signes 24 heures après l'intoxication et 81% des patients ont été vus au CHU entre 24 et 48 heures. Les signes cliniques du chélonitoxisme sont polymorphes : 86% ont présenté une asthénie, 91% des nausées, 25% des vomissements, 71% des céphalées et 21% des stomatites. A l'issue de l'hospitalisation, 99% des malades ont été guéris et un patient est décédé. Les traitements étaient symptomatiques. Conclusion : L'intoxication par tortue de mer est généralement bénigne. La prise en charge est symptomatique.

GENETIC AND MORPHOLOGIC CHARACTERIZATION OF DIASCHISTORCHIS PANDUS (DIGENEA: PRONOCEPHALIDAE) TREMATODES EXTRACTED FROM HAWKSBILL TURTLES, ERETMOCHELYS IMBRICATA (TESTUDINES: CHELONIIDAE), IN GRENADA, WEST INDIES.

The hawksbill turtle Eretmochelys imbricata is a critically endangered species with a worldwide distribution. Limited information is available about the naturally occurring intestinal parasites of this species and what impact these parasites may have on the health of the hawksbill turtle. Diaschistorchis pandus was identified postmortem in 5 hawksbill turtles from Grenada, West Indies, using morphologic characterization. Sanger sequencing was performed for conserved ribosomal regions (5.8S, ITS2, 28S) and the mitochondrial cytochrome c oxidase subunit 1 gene (COI). Phylogenetic analysis of the 28S rRNA gene sequence data shows D. pandus clustering with other trematodes in the family Pronocephalidae, corroborating morphological classification. No genetic sequences have been previously reported for this trematode species, which has limited the collection of objective epidemiological data about this parasite of marine turtles.

Detection of high heteroplasmy in complete loggerhead and hawksbill sea turtles mitochondrial genomes using RNAseq.

Sea turtle populations around the world face rapid decline due to the effect of anthropogenic and environmental factors. Among the affected populations are those of hawksbill turtles (Eretmochelys imbricata) and loggerhead turtles (Caretta caretta), which is why a greater effort is currently being made in their monitoring and tracing. The intragenic degree of heteroplasmic mutations, commonly associated with diseases of variable symptoms, has not been analyzed in these species. In this study, heteroplasmy in the complete mitogenome (mtDNA) of three loggerhead turtles and one hawksbill turtle was identified from data obtained by RNAseq. Individuals Cc3, Ei1, Cc1 and Cc2 presented 0.3, 1.7, 1.8 and 7.1% of heteroplasmic mutations in all their mtDNA, respectively. The protein-coding genes that presented the highest percentage of heteroplasmy were ND4 and ND5 in individual Cc2 with 16 and 38.6%, respectively. Of the tRNA genes, only tRNATyr was heteroplasmic in the four individuals with 5.63% (Cc1), 25.35% (Ei1 and Cc2) and 49.3% (Cc3). In this study, we identified the critical sites of heteroplasmy in each individual and the genetic variability of their mitogenomes. The data obtained represents the baseline for future projects that evaluate the population status of these species.

Long-term monitoring of marine turtle nests in northeastern Brazil / Monitoramento de longo prazo de ninhos de tartarugas marinhas no nordeste do Brasil

Abstract: This study monitored marine turtle nests in a region known as the Potiguar Basin, which stretches from the northern region of Rio Grande do Norte State (5°4'1.15" S, 36°4'36.41" W) to eastern Ceará State (4°38'48.28" S, 37°32'52.08" W) in Brazil. We collected data from January 2011 to December 2019 to identify species of sea turtles that spawn in the basin, to analyze the nesting spatial-temporal pattern and nests characteristics, and to record effects of environmental and anthropic factors on nests. A field team examined sea turtle tracks and nests signs. Turtle clutches were monitored daily until hatchings emerged from the nests. We monitored nests of hawksbill (Eretmochelys imbricata; n = 238) and olive Ridley turtles (Lepidochelys olivacea; n = 103). The nesting season for E. imbricata occurred between December and May and for L. olivacea from March to August. Hawksbills had clutch size, incubation time, number of unhatched eggs, and dead hatchlings higher than olive Ridley turtles; nevertheless, they presented lower hatching success. Precipitation between 0 and 22 mm and relative humidity (RH) higher than 69% increased the hatching success rate for E. imbricata; however, rainfall above 11 mm and RH 64% had the same effect for L. olivacea. Signs of egg theft and human presence (e.g. vehicle traffic and plastic residues on the beach) were recorded and are considered threats to nests. The results of our long-term monitoring study in the Potiguar Basin provide basis for the implementation of mitigation measures and adoption of management policies at nesting beaches in this Brazilian region.

Resumo: Este estudo permitiu o monitoramento de ninhos de tartarugas marinhas em uma região conhecida como Bacia Potiguar, que se estende da região norte do Estado do Rio Grande do Norte (5 ° 4'1,15 "S, 36 ° 4'36,41" W) até o leste do Estado do Ceará (4 ° 38'48,28 "S, 37 ° 32'52,08" W), no Brasil. Coletamos dados de janeiro de 2011 a dezembro de 2019 com o objetivo de identificar as espécies de tartarugas marinhas que desovam na bacia, analisar o padrão espaço-temporal de nidificação, as características dos ninhos, e registrar os efeitos de fatores ambientais e antrópicos. Uma equipe de campo examinou rastros de tartarugas marinhas e sinais de ninhos. As ninhadas das tartarugas foram monitoradas diariamente até que os filhotes emergissem dos ninhos. Monitoramos ninhos de tartarugas-de-pente (Eretmochelys imbricata; n = 238) e tartarugas-oliva (Lepidochelys olivacea; n = 103). A época de nidificação para E. imbricata ocorreu entre dezembro e maio e para L. olivacea de março a agosto. Tartarugas-de-pente apresentaram maior tamanho das ninhadas, tempo de incubação, número de ovos não eclodidos e número de filhotes mortos quando comparado com tartarugas-oliva; no entanto, apresentaram menor sucesso de eclosão. Precipitação entre 0 e 22 mm e umidade relativa (UR) maior que 69% aumentaram a taxa de sucesso de eclosão para E. imbricata; entretanto, chuvas acima de 11 mm e UR 64% tiveram o mesmo efeito para L. olivacea. Sinais de roubo de ovos e presença humana (por exemplo, tráfego de veículos e resíduos de plástico na praia) foram registrados e são considerados ameaças aos ninhos. Os resultados do nosso estudo de monitoramento de longo prazo na Bacia Potiguar fornecem base para a implementação de medidas de mitigação e adoção de políticas públicas em praias de desova nesta região brasileira.

Buried treasure-marine turtles do not 'disguise' or 'camouflage' their nests but avoid them and create a decoy trail.

After laying their eggs and refilling the egg chamber, sea turtles scatter sand extensively around the nest site. This is presumed to camouflage the nest, or optimize local conditions for egg development, but a consensus on its function is lacking. We quantified activity and mapped the movements of hawksbill (Eretmochelys imbricata) and leatherback (Dermochelys coriacea) turtles during sand-scattering. For leatherbacks, we also recorded activity at each sand-scattering position. For hawksbills, we recorded breathing rates during nesting as an indicator of metabolic investment and compared with published values for leatherbacks. Temporal and inferred metabolic investment in sand-scattering was substantial for both species. Neither species remained near the nest while sand-scattering, instead moving to several other positions to scatter sand, changing direction each time, progressively displacing themselves from the nest site. Movement patterns were highly diverse between individuals, but activity at each sand-scattering position changed little between completion of egg chamber refilling and return to the sea. Our findings are inconsistent with sand-scattering being to directly camouflage the nest, or primarily for modifying the nest-proximal environment. Instead, they are consistent with the construction of a series of dispersed decoy nests that may reduce the discovery of nests by predators.

Data on heteroplasmic mutations in mitochondrial genomes of loggerhead and hawksbill sea turtles: First approach.

The populations of loggerhead (Caretta caretta) and hawksbill (Eretmochelys imbricata) sea turtles are suffering an exponential decline due to anthropic and environmental actions that threaten their survival. In these turtle populations, the degree of heteroplasmic mutations commonly related with pathologies, has not been studied. In this data report, the specifications of each heteroplasmic site (region, mutation, length) and the percentage of heteroplasmy of each gene for four mitochondrial genomes of turtles (loggerhead: Cc1, Cc2, Cc3 and hawksbill: Ei1) are presented. The highest value of heteroplasmy in tRNA was of 83.33% for the Cc2 turtle (tRNASer gene), in protein coding genes was 38.62% for Cc2 (ND5), and in rRNA genes of 0.74% for Ei1 turtle (rRNA-16S). The variability data obtained will be useful for further conservation projects, evolution studies and population health of these species. This is the first study of heteroplasmy in complete mitogenomes of loggerhead and hawksbill turtles.

Fidelity to foraging sites after long migrations.

Patterns of animal movement associated with foraging lie at the heart of many ecological studies and often animals face decisions of staying in an environment they know versus relocating to new sites. The lack of knowledge of new foraging sites means there is risk associated with a decision to relocate (e.g. poor foraging) as well as a potential benefit (e.g. improved foraging). Using a unique long-term satellite tracking dataset for several sea turtle species, combined with capture-mark-recapture data extending over 50 years, we show how, across species, individuals generally maintain tight fidelity to specific foraging sites after extended (up to almost 10,000 km) migration to and from distant breeding sites as well as across many decades. Migrating individuals often travelled through suitable foraging areas en route to their 'home' site and so extended their journeys to maintain foraging site fidelity. We explore the likely mechanistic underpinnings of this trait, which is also seen in some migrating birds, and suggest that individuals will forgo areas of suitable forage encountered en route during migration when they have poor knowledge of the long-term suitability of those sites, making relocation to those sites risky.

First Report of Pyelosomum Cochlear Looss 1899 (Digenea: Pronocephalidae) in a Hawksbill Turtle - Eretmochelys Imbricata L. Found in Brazilian Coast.

Pyelosomum cochlear Looss 1899 (Digenea: Pronocephalidae) is a parasite exclusive to sea turtles, having been described in the green turtle (Chelonia mydas) in Egypt, the USA, Panama, Costa Rica and Brazil as well as the olive ridley turtle (Lepidochelys olivacea) in Brazil. The present note describes the first occurrence of P. cochlear in a hawksbill turtle (Eretmochelys imbricata) found on the coast of Brazil.

Conjunctival bacterial flora and antimicrobial susceptibility of captive and free-living sea turtles in Brazil.

PURPOSE: To describe the aerobic conjunctival bacterial flora of 3 especies of free-living and under human care sea turtles and determine its antimicrobial susceptibility in vitro. METHOD: Thirty-six sea turtles (72 eyes), juveniles and adults, 7 free-living Chelonia mydas and 8 Chelonia mydas, 4 Caretta caretta, 11 Eretmochelys imbricata, and 6 Lepidochelys olivacea under human care, were evaluated. Conjunctival cultures were collected for identification of aerobic bacteria and antimicrobial susceptibility testing for ciprofloxacin, chloramphenicol, gentamicin, neomycin, oxacillin, polymyxin B, tetracycline, and tobramycin using antibiotic disks. Bacterial strains showing no sensitivity to 4 or more antimicrobials were considered multiresistant to this panel. RESULTS: Bacterial growth was observed in 12/14 (85.71%) samples in the free-living sea turtles, and there was growth in 100% (58/58) of the samples from captive animals. There were 94 strains isolated and 15 species identified. There was a predominance of Gram-positive bacteria in free-living Chelonia mydas, most of which were Bacillus and Staphylococcus. The most commonly isolated Gram-negative species were enterobacteria for free-living and under human care animals. The strains were predominantly sensitive to ciprofloxacin and tobramycin, and less sensitive to oxacillin or polymyxin B. Ten multiresistant strains were isolated. Yeast were identified in 13.89% (10/72) of the samples. CONCLUSIONS: These results, showing differences in the conjunctival bacterial flora of free-living and captive animals, may be helpful for diagnosis and treatment of ocular disorders in sea turtles.

Nuevos marcadores mitocondriales mejoran la filogenia de la tortuga carey Eretmochelys imbricata (Testudines: Cheloniidae) / New mitochondrial markers improve the phylogeny of the hawksbill turtle Eretmochelys imbricata (Testudines: Cheloniidae)

Las tortugas marinas (Cheloniidae) son un grupo de siete especies originadas en el cretaceo. Analisis de secuencias parciales de DNA mitocondrial han revelado inconsistencias filogeneticas dentro de este grupo de quelonios. Sin embargo, estos marcadores mitocondriales han permitido entender y dilucidar la composicion de las poblaciones en areas de forrajeo, habitos reproductivos, inferencias de patrones de migracion y tambien definir las unidades de manejo en el mundo, con el fin de proponer planes de manejo y conservacion. El objetivo de este estudio fue evaluar la posicion de la tortuga carey E. imbricata dentro de la familia Cheloniidae y la filogenia de las tortugas marinas utilizando genes mitocondriales codificantes de proteinas, genes ribosomicos y el genoma mitocondrial completo de la tortuga carey anidante del Caribe colombiano, al compararlo con las otras seis especies de tortugas marinas disponibles en GenBank. Se utilizaron cuatro metodos de inferencias filogeneticas: Neighbor-Joining (NJ), Maxima Verosimilitud (ML), Maxima Parsimonia (MP) e Inferencia Bayesiana (IB). Los arboles NJ, ML, MP e IB mostraron que ND2, COX1, 16S ARNr, ND5, 12S ARNr, ND4, COX3 y ND1 son los marcadores que presentan una mejor resolucion filogenetica con sustentos bootstrap entre 89,0% y 99,98%. Los genes ATP6, ATP8, COX2, ND3, ND4L y ND5 presentaron politomias y establecieron relaciones filogeneticas equivocadas. El analisis con el mitogenoma completo presento arboles altamente sustentados (bootstrap de 98,0%) en comparacion con el analisis con marcadores individuales. Los arboles obtenidos con el gen ND2 e IB resolvieron con buen sustento las relaciones evolutivas entre las especies comparadas, consolidandose la posicion de E. imbricata dentro de la tribu Carettini con probabilidad posterior de 0,98-1,0. Los marcadores ND2, ND5, ND4, COX3 y ND1 no han sido utilizados en trabajos previos y representan una nueva alternativa para explicar la filogenia en este grupo de reptiles marinos. En el presente caso utilizando mitogenomas completos se obtuvieron arboles robustos y altamente sustentados.

The sea turtles (Cheloniidae) are a group of seven species of cretaceous origin. Analyses of partial mitochondrial sequences have revealed phylogenetic inconsistences within this group. Nevertheless, these mitochondrial markers have allowed us to understand, explain and clarify population composition in areas of foraging, reproductive habits, inferences of migration patterns and, also, to define management units in the world, in order to trace conservation and monitoring plans. In this study, four methods were evaluated and compared for phylogenetic inference (Neighbor-Joining-NJ, Maximum Likelihood-ML, Maximum Parsimony-MP and Bayesian inference-BI) by using coding genes, ribosomal genes and full mitogenomes of the hawksbill, E. imbricata, and other six species of sea turtles obtained from GenBank. The sequences were analyzed independently and jointly to identify the method and marker that better explain the phylogenetic relationships among this group of reptiles. The NJ, ML, MP and BI trees showed that ND2, COX1, 16S rRNA, ND5, 12S rRNA, ND4 and COX3 are the markers that give phylogenetic trees with better resolution and support, with bootstrap values ranging from 89.0% to 99.98%. ATP6, ATP8, COX2, ND1, ND3, ND5 and ND4L genes presented polytomies. The analysis with full mitogenome often provides highly supported trees (bootstrap 98.0%) compared with single marker analysis. Trees obtained with the BI method and the ND2 gene is the one that better resolved the evolutionary relationships among the species, consolidating the position of E. imbricata within the Carettini tribe with a value of posterior probability of 0.98-1.0. The markers ND2, ND4, ND5 and COIII, not used in previous works, represent a new alternative to explain the phylogeny in this group of marine reptiles. In the present study, a complete mitogenome analysis produced robust and highly supported trees.

Plasma biochemistry values in wild female hawksbill turtle (Eretmochelys imbricata) during nesting in Mexican coast / Valores de bioquímica plasmática em tartaruga de pente (Eretmochelys imbricata) durante a época de desova na costa mexicana

To obtain plasma biochemistry values, blood was collected for 47 nesting females of apparently healthy Eretmochelys imbricata sea turtles using sodium heparin as an anticoagulant. Blood samples were collected in April-Jun for two years (nesting season). Hematologic characteristics, including packed cell volume, white blood cell counts, red blood cell count and hemoglobin level; and plasma chemistry values, including creatinine, blood urea nitrogen, uric acid, triglyceride, total cholesterol, and glucose were measured. The data generated from this study may be useful for clinical assessment of health and disease of wild hawksbill sea turtles on nearshore habitats in the Gulf of Mexico, thus contributing to a conservation of this species.(AU)

Para obter valores da bioquímica plasmática, foram coletadas amostras de sangue durante a desova de 47 tartarugas marinhas fêmeas aparentemente saudáveis da espécie Eretmochelys imbricata, utilizando heparina sódica como anticoagulante. Amostras de sangue foram coletadas durante dois anos entre os meses de abril e junho (época de nidificação). Mediu-se os parâmetros hematológicos (incluindo hematócrito, contagem de glóbulos brancos e vermelhos e nível de hemoglobina) e os valores da bioquímica plasmática (incluindo creatinina, ureia, ácido úrico, triglicérides, colesterol total e glicose). Os dados gerados a partir deste estudo podem ser úteis para a avaliação clínica de saúde e de doença em tartarugas-de-pente em habitats próximos ao litoral no Golfo do México, contribuindo para a conservação dessa espécie.(AU)

Oxidative stress biomarkers and organochlorine pesticides in nesting female hawksbill turtles Eretmochelys imbricata from Mexican coast (Punta Xen, Mexico).

Because of their vulnerable population status, assessing exposure levels and impacts of toxicants on the health status of Gulf of Mexico marine turtle populations is essential, and this study was aimed to obtain baseline information on oxidative stress indicators in hawksbill sea turtle (Eretmochelys imbricata). In order to evaluate the health status of sea turtles and the effect of organochlorine compounds (OC) in the southern part of the Gulf of Mexico, we searched for relationships between carapace size and the activity of antioxidant enzymes in the blood of the hawksbill sea turtle. The level of oxidative stress biomarkers such as the enzymes catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), glutathione S-transferase (GST), and acetylcholinesterase (Ache) in the hawksbill sea turtle was analysed during nesting season in the years 2014-2015 at Punta Xen (Campeche, Mexico). The results of this study provide insight into data of antioxidant enzyme activities in relation to contaminant OCPs in hawksbill sea turtles and the possible health impacts of contaminant in sea turtles.

Profiles of environmental contaminants in hawksbill turtle egg yolks reflect local to distant pollution sources among nesting beaches in the Yucatán Peninsula, Mexico.

Knowledge of spatial variation in pollutant profiles among sea turtle nesting locations is limited. This poses challenges in identifying processes shaping this variability and sets constraints to the conservation management of sea turtles and their use as biomonitoring tools for environmental pollutants. We aimed to increase understanding of the spatial variation in polycyclic aromatic hydrocarbon (PAH), organochlorine pesticide (OCP) and polychlorinated biphenyl (PCB) compounds among nesting beaches. We link the spatial variation to turtle migration patterns and the persistence of these pollutants. Specifically, using gas chromatography, we confirmed maternal transfer of a large number of compounds (n = 68 out of 69) among 104 eggs collected from 21 nests across three nesting beaches within the Yucatán Peninsula, one of the world's most important rookeries for hawksbill turtles (Eretmochelys imbricata). High variation in PAH profiles was observed among beaches, using multivariate correspondence analysis and univariate Peto-Prentice tests, reflecting local acquisition during recent migration movements. Diagnostic PAH ratios reflected petrogenic origins in Celestún, the beach closest to petroleum industries in the Gulf of Mexico. By contrast, pollution profiles of OCPs and PCBs showed high similarity among beaches, reflecting the long-term accumulation of these pollutants at regional scales. Therefore, spatial planning of protected areas and the use of turtle eggs in biomonitoring needs to account for the spatial variation in pollution profiles among nesting beaches.

Evidence of opposing fitness effects of parental heterozygosity and relatedness in a critically endangered marine turtle?

How individual genetic variability relates to fitness is important in understanding evolution and the processes affecting populations of conservation concern. Heterozygosity-fitness correlations (HFCs) have been widely used to study this link in wild populations, where key parameters that affect both variability and fitness, such as inbreeding, can be difficult to measure. We used estimates of parental heterozygosity and genetic similarity ('relatedness') derived from 32 microsatellite markers to explore the relationship between genetic variability and fitness in a population of the critically endangered hawksbill turtle, Eretmochelys imbricata. We found no effect of maternal MLH (multilocus heterozygosity) on clutch size or egg success rate, and no single-locus effects. However, we found effects of paternal MLH and parental relatedness on egg success rate that interacted in a way that may result in both positive and negative effects of genetic variability. Multicollinearity in these tests was within safe limits, and null simulations suggested that the effect was not an artefact of using paternal genotypes reconstructed from large samples of offspring. Our results could imply a tension between inbreeding and outbreeding depression in this system, which is biologically feasible in turtles: female-biased natal philopatry may elevate inbreeding risk and local adaptation, and both processes may be disrupted by male-biased dispersal. Although this conclusion should be treated with caution due to a lack of significant identity disequilibrium, our study shows the importance of considering both positive and negative effects when assessing how variation in genetic variability affects fitness in wild systems.

Blood gases, biochemistry and haematology of Galápagos hawksbill turtles (Eretmochelys imbricata).

The hawksbill turtle, Eretmochelys imbricata, is a marine chelonian with a circum-global distribution, but the species is critically endangered and has nearly vanished from the eastern Pacific. Although reference blood parameter intervals have been published for many chelonian species and populations, including nesting Atlantic hawksbills, no such baseline biochemical and blood gas values have been reported for wild Pacific hawksbill turtles. Blood samples were drawn from eight hawksbill turtles captured in near shore foraging locations within the Galápagos archipelago over a period of four sequential years; three of these turtles were recaptured and sampled on multiple occasions. Of the eight sea turtles sampled, five were immature and of unknown sex, and the other three were females. A portable blood analyzer was used to obtain near immediate field results for a suite of blood gas and chemistry parameters. Values affected by temperature were corrected in two ways: (i) with standard formulas and (ii) with auto-corrections made by the portable analyzer. A bench top blood chemistry analyzer was used to measure a series of biochemistry parameters from plasma. Standard laboratory haematology techniques were employed for red and white blood cell counts and to determine haematocrit manually, which was compared to the haematocrit values generated by the portable analyzer. The values reported in this study provide reference data that may be useful in comparisons among populations and in detecting changes in health status among Galápagos sea turtles. The findings might also be helpful in future efforts to demonstrate associations between specific biochemical parameters and disease or environmental disasters.

Ecological regime shift drives declining growth rates of sea turtles throughout the West Atlantic.

Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory, primarily herbivorous mega-consumers that may migrate over hundreds to thousands of kilometers. Our dataset, the largest ever compiled for sea turtles, has 9690 growth increments from 30 sites from Bermuda to Uruguay from 1973 to 2015. Using generalized additive mixed models, we evaluated covariates that could affect growth rates; body size, diet, and year have significant effects on growth. Growth increases in early years until 1999, then declines by 26% to 2015. The temporal (year) effect is of particular interest because two carnivorous species of sea turtles-hawksbills, Eretmochelys imbricata, and loggerheads, Caretta caretta-exhibited similar significant declines in growth rates starting in 1997 in the West Atlantic, based on previous studies. These synchronous declines in productivity among three sea turtle species across a trophic spectrum provide strong evidence that an ecological regime shift (ERS) in the Atlantic is driving growth dynamics. The ERS resulted from a synergy of the 1997/1998 El Niño Southern Oscillation (ENSO)-the strongest on record-combined with an unprecedented warming rate over the last two to three decades. Further support is provided by the strong correlations between annualized mean growth rates of green turtles and both sea surface temperatures (SST) in the West Atlantic for years of declining growth rates (r = -.94) and the Multivariate ENSO Index (MEI) for all years (r = .74). Granger-causality analysis also supports the latter finding. We discuss multiple stressors that could reinforce and prolong the effect of the ERS. This study demonstrates the importance of region-wide collaborations.

Complete mitochondrial genome of the nesting Colombian Caribbean Hawksbill Turtle.

The hawksbill turtle, Eretmochelis imbricata (Linnaeus, 1766), is an endangered sea turtle in Colombian Caribbean beach. In this study, we report the complete mitochondrial DNA sequences of hawksbill turtle. The entire genome comprised 16,386 base pairs, and a nucleotide frequency of T: 25.6%, C: 26.9%, A: G 35.4% and 12.1%. The mitogenome sequence of hawksbill turtle would contribute to better understand population genetics, and evolution of sea turtles. Molecule was deposited at the GenBank database under the accession number KP221806.