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Incubation Temperature Effects on Loggerhead (Caretta caretta) and Green (Chelonia mydas) Sea Turtle Hatchling VigorUnknown Date (has links)
Climate change has the potential to expose sea turtle nests to higher temperatures, which may negatively impact sea turtle hatchling vigor. In this study, loggerhead and green hatchlings were sampled from the Boca Raton, Florida beach and via lab incubation, and hatchling vigor was determined. Elevated nest temperatures decreased loggerhead and green turtle hatchling performance and corticosterone levels, with the most significant effects found in hatchlings exposed to maximum incubation temperatures above 35°C during late development. Lab-incubated loggerhead post-hatchling corticosterone levels and growth rates were also determined. The differences seen in corticosterone levels with overall nest incubation temperatures, mean temperatures during early, middle or late stages of development, and its negative correlation with hatchling performance improves our understanding of the underlying physiological mechanisms linking elevated incubation temperatures and sub-lethal physiological effects that may significantly impact hatchling survival, a critical step for sea turtle conservation in south Florida and elsewhere. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
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Investigating variation in the life-history strategy of marine turtlesBradshaw, Philip James January 2017 (has links)
Understanding the degree of connectivity among populations, forming migratory links and evaluating factors that influence reproductive fitness is fundamental for the successful management of migratory species of conservation concern. In this thesis I focus on a regionally important rookery of green turtles (Chelonia mydas) at Alagadi beach in northern Cyprus that has been intensively studied since 1992. I employ high resolution genetic markers with different modes of inheritance to reveal fine scale population structuring among four rookeries within a 200 km stretch of shoreline. The relative importance of four foraging areas and the annual contribution from each site to the breeding cohort are evaluated using the stable isotope ratios of the turtles calibrated by satellite telemetry. The stable isotope ratios of the turtles reveal that a previous undisclosed foraging site at Lake Bardawil in Egypt is critical for the population recovery of the Alagadi rookery. The temporal consistency of stable isotope ratios reaffirm that green turtles exhibit high fidelity to foraging sites allowing the evaluation of foraging area effects on reproductive traits to be evaluated over multiple seasons. I investigate the population sub-structuring of the Alagadi nesting aggregation grouped by the foraging area used. The absence of genetic structure supported the Learning Migration Goal Theory and provided evidence that the significant among site phenotypic variability in the body size of recruits, the length of interbreeding intervals and the date that the first nest of the season was made is a result of foraging areas effects. No significant among site phenotypic variability was found for the size or number of clutches laid. Among site variability in interbreeding intervals resulted in substantial variation in the reproductive potential of individuals due to assumed differences in resource availability and environmental factors. The multilocus genotypes generated for 243 nesting females were employed to reconstruct the first wild marine turtle pedigree using a full-likelihood sib-ship reconstruction approach. This revealed that the effective contribution to the next generation was unequal and allowed a minimum age to maturity to be estimated from parent – offspring assignations. However, sample size constraints prevented accurate estimates for the narrow-sense heritability of the five morphological and life-history traits from the quantitative genetic analysis. The multifaceted approach taken here to unravel the cryptic life-history of marine turtles emphasises the importance of long-term individual-based monitoring and the data generated can be employed to advise conservation strategy for this critically endangered regional management unit.
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Jaguar (Panthera onca) activity on the beach of Tortuguero National Park, Costa RicaRosendal, Erik January 2011 (has links)
The jaguars (Panthera onca) of Tortuguero National Park, Costa Rica, sometimes kills and eats green sea turtles (Chelonia mydas), they also, though less often, kill and eat leatherback sea turtles (Dermochelys coriacea). The three species are considered endangered and are listed in CITES. It was the aim of this study to find out more about the jaguars behaviour in the area. To discern any patterns of jaguar and turtle activity on the beach the number of tracks per eighth of a mile was recorded on a daily basis for 26 days and then analyzed. It was also considered to be of interest to determine how many jaguars could be responsible for the predation of sea turtles. In addition to this average beach width was measured for each eighth of a mile. There was a noticeable difference in jaguar activity on the beach between days of recording. Analysis found that the beach width could possibly have a small positive effect on jaguar activity. No correlation was found between jaguar and turtle activity. It is believed that the reason that there was no correlation between jaguar activity and turtle activity was due to most of the tracks used to estimate turtle activity had originated from leatherback turtles, which are not as often predated by jaguars as the green turtle. An estimation of five or six jaguars was made using photographs of pugmarks and a method of track discrimination together with information from personnel from the Jalova station.
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Weather patterns associated with green turtle hypothermic stunning events in St. Joseph Bay and Mosquito Lagoon, FloridaRoberts, Kelsey 01 January 2013 (has links)
January of 2010 brought record-breaking cold temperatures to Florida. Such freeze events can upset vulnerable populations of marine life and other species that rely on stable water temperatures. Sea turtles are one group of species that are particularly susceptible to abrupt drops in water temperature. When water temperatures drop below 10°C, a mass hypothermic stunning, or cold-stunning, event for sea turtles can be expected, with many debilitated turtles washing onshore with a very limited time window to be rehabilitated (Foley et al. 2007). The species of sea turtle that appears to cold-stun with the most frequency is the green turtle, especially juveniles. The green turtle represented the vast majority of marine turtles that were rescued during the 2010 cold-stun event.
Therefore, accurate weather pattern recognition of marine cold snaps, or freezes, can alert sea turtle rescue groups and rehabilitation facilities in advance of any event, improving their readiness and response times, and ultimately preventing population declines. The proposed research fills this need by providing a qualitative analysis of select years for comparable atmospheric processes that could result in moderate to severe hypothermic stunning events. The 2010 event, along with other significant events, were examined using in situ air temperature, water temperature and wind data near two locations in Florida where hypothermic stunning events occurred: St. Joseph Bay and Mosquito Lagoon. These atmospheric parameters were represented graphically, depicting how each variable contributed to shaping an event.
Cold stunning events were found to be primarily driven by frigid air temperatures and a subsequent decrease in water temperatures. Differences between the two event classifications, moderate and severe, are contingent upon the duration of the cold spell, not necessarily how quickly the water temperature dropped below the 10°C threshold value. Results suggest that repeated, quick exposure to cold air temperatures may influence the severity of a hypothermic stunning event. This research could be utilized in the formation of a forecasting model or strategy to efficiently alert the Florida Sea Turtle Stranding and Salvage Network (STSSN) to a potential sharp drop in water temperatures and, consequently, many debilitated sea turtles.
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Helmintofauna de Chelonia mydas necropsiadas na base do Projeto Tamar-Ibama em Ubatuba, Estado de São Paulo, Brasil /Werneck, Max Rondon. January 2007 (has links)
Orientador: Reinaldo José da Silva / Banca: Tânia de Freitas Raso / Banca: Alessandro Francisco Talamini do Amarante / Resumo: O presente estudo relata o resultado da análise parasitológica de 62 exemplares juvenis da espécie Chelonia mydas (L.) necropsiadas no Centro de Reabilitação de Tartarugas Marinhas do Projeto TAMAR-IBAMA na região de Ubatuba, Litoral Norte do Estado de São Paulo, Brasil. Trinta e três animais apresentaram parasitas da classe Trematoda das seguintes espécies: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) e Metacetabulum invaginatum (Metacetabulidae). A prevalência variou de 3 a 66,7%, sendo as espécies N. travassosi, D. proteus e M. invaginatum, aquelas de maior prevalência nos animais estudados. A intensidade média de infecção foi maior na espécie da família Metacetabulidade (80,2) em relação às famílias Angiodictyidae (35,7) e Pronocephalidae (7,3). Em 13 (39,4%) animais o parasitismo foi monoespecífico, com predomínio das espécies N. travassosi e D. proteus. Por outro lado, em 20 (60,6%) tartarugas foi observada associação entre parasitas, sendo encontrado 2, 3, 4 ou 5 parasitas, sendo as freqüências desta associação de 33,3%, 0,06%, 0,18% e 0,03%, respectivamente. Observamos associação entre sinais de debilidade e carga parasitária (p = 0,03). / Abstract: A parasitological survey of 62 juvenile specimens of the Chelonia mydas (L.) necropsied in the Centro de Reabilitação de Tartarugas Marinhas of the Projeto TAMAR-IBAMA, Ubatuba city, North Coast of the São Paulo State, Brazil, is presented. Thirty three animals were parasitized by flukes of the following species: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) and Metacetabulum invaginatum (Metacetabulidae). The prevalence varied from 3 to 66.7%, and the species N. travassosi, D. proteus and M. invaginatum, presented the higher prevalence among the studied animals. The mean intensity of infection was higher in the species of the family Metacetabulidade (80.2) in comparison to the families Angiodictyidae (35.7) and Pronocephalidae (7.3). In 13 (39.4%) animals the parasitism was monospecific, and the species N. travassosi and D. proteus were predominates. On the other hand, in 20 (60.6%) sea turtles an association among parasites was observed. It was found 2, 3, 4 or 5 parasites and the frequencies of this association were 33.3%, 0.06%, 0.18% and 0.03%, respectively. The relation between signs of weakness and mean intensity of infection was also observed (p = 0.03). / Mestre
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Helmintofauna de Chelonia mydas necropsiadas na base do Projeto Tamar-Ibama em Ubatuba, Estado de São Paulo, BrasilWerneck, Max Rondon [UNESP] 12 February 2007 (has links) (PDF)
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werneck_mr_me_botib.pdf: 1984153 bytes, checksum: 8fe7df123d7db009ca20e57b7b9f8439 (MD5) / Universidade Estadual Paulista (UNESP) / O presente estudo relata o resultado da análise parasitológica de 62 exemplares juvenis da espécie Chelonia mydas (L.) necropsiadas no Centro de Reabilitação de Tartarugas Marinhas do Projeto TAMAR-IBAMA na região de Ubatuba, Litoral Norte do Estado de São Paulo, Brasil. Trinta e três animais apresentaram parasitas da classe Trematoda das seguintes espécies: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) e Metacetabulum invaginatum (Metacetabulidae). A prevalência variou de 3 a 66,7%, sendo as espécies N. travassosi, D. proteus e M. invaginatum, aquelas de maior prevalência nos animais estudados. A intensidade média de infecção foi maior na espécie da família Metacetabulidade (80,2) em relação às famílias Angiodictyidae (35,7) e Pronocephalidae (7,3). Em 13 (39,4%) animais o parasitismo foi monoespecífico, com predomínio das espécies N. travassosi e D. proteus. Por outro lado, em 20 (60,6%) tartarugas foi observada associação entre parasitas, sendo encontrado 2, 3, 4 ou 5 parasitas, sendo as freqüências desta associação de 33,3%, 0,06%, 0,18% e 0,03%, respectivamente. Observamos associação entre sinais de debilidade e carga parasitária (p = 0,03). / A parasitological survey of 62 juvenile specimens of the Chelonia mydas (L.) necropsied in the Centro de Reabilitação de Tartarugas Marinhas of the Projeto TAMAR-IBAMA, Ubatuba city, North Coast of the São Paulo State, Brazil, is presented. Thirty three animals were parasitized by flukes of the following species: Cricocephalus albus, Cricocephalus megastomum, Pleurogonius longiusculus, Pronocephalus obliquus (Pronocephalidae), Deuterobaris proteus, Neoctangium travassosi, Polyangium linguatula, Microscaphidium reticulare (Angiodictyidae) and Metacetabulum invaginatum (Metacetabulidae). The prevalence varied from 3 to 66.7%, and the species N. travassosi, D. proteus and M. invaginatum, presented the higher prevalence among the studied animals. The mean intensity of infection was higher in the species of the family Metacetabulidade (80.2) in comparison to the families Angiodictyidae (35.7) and Pronocephalidae (7.3). In 13 (39.4%) animals the parasitism was monospecific, and the species N. travassosi and D. proteus were predominates. On the other hand, in 20 (60.6%) sea turtles an association among parasites was observed. It was found 2, 3, 4 or 5 parasites and the frequencies of this association were 33.3%, 0.06%, 0.18% and 0.03%, respectively. The relation between signs of weakness and mean intensity of infection was also observed (p = 0.03).
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Incid?ncia de fibropapilomatose em tartarugas marinhas na Bacia Potiguar RN/CESilva J?nior, Edson Soares da 19 December 2016 (has links)
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Previous issue date: 2016-12-19 / As cinco esp?cies de tartarugas marinhas que ocorrem no litoral brasileiro est?o classificadas como esp?cies em risco de extin??o pelas listas mundiais de esp?cies amea?adas. Tal status ? decorrente das diferentes amea?as que esses animais v?m sofrendo no decorrer das ?ltimas d?cadas, dentre estas a destrui??o do habitat, fotopolui??o, pesca incidental, tr?fego de ve?culos e preda??o de ovos. Outra consider?vel amea?a a esses animais, descrita na literatura, ? a ocorr?ncia da fibropapilomatose. Esta doen?a acomete as tartarugas marinhas, em especial indiv?duos juvenis da esp?cie Chelonia mydas, embora tenha sido descrito tamb?m nas demais esp?cies. Este trabalho pretende investigar a distribui??o espacial e temporal dos registros de tartarugas marinhas com fibropapilomatose que encalham, vivos ou mortos, entre as praias dos munic?pios de Icapu?/CE at? Cai?ara do Norte/RN, bem como analisar os aspectos histopatol?gicos das les?es. Para isso foram realizados monitoramentos di?rios, utilizando-se quadriciclos, a fim de registrar a ocorr?ncia de tartarugas marinhas nas praias da Bacia Potiguar RN / CE. Os animais que foram encontrados mortos, dependendo do estado da carca?a, foram avaliados quanto ? esp?cie, ao n?mero e posicionamento dos tumores, fotografados e georreferenciados. Os animais vivos foram resgatados e translocados para a Base de Reabilita??o do Projeto Cet?ceos da Costa Branca/UERN-Areia Branca onde foi realizado o procedimento de contagem e localiza??o dos tumores. Para o desenvolvimento da pesquisa est?o sendo utilizados dados coletados entre os anos de 2011 e 2015. Dentre as 3.960 tartarugas marinhas encalhadas, 680 apresentaram tumores sugestivos de fibropapilomatose, valores estes que apresentaram crescimento durante os anos estudados. No que diz respeito a varia??o por trecho de monitoramento, a maior frequ?ncia de animais acometidos pela doen?a foi registrada no trecho C correspondente a "Guamar?-Macau?. Quanto a fase de desenvolvimento, a maior parte dos indiv?duos acometidos estavam no est?gio juvenil, por?m tamb?m houve registro de animais adultos e subadultos acometidos pela doen?a. As les?es se configuram por apresentarem hiperplasia da epiderme, do conjuntivo, desorganiza??o de fibras col?genas, hiperqueratiniza??o de regi?es dentro do tecido conjuntivo e vacuoliza??o no citoplasma. Al?m disso, foram observados ovos de parasitas presentes dentro da estrutura do fibropapiloma, al?m das proje??es papilares que marcam de maneira peculiar a estrutura tumoral. A Bacia Potiguar RN / CE mostrou-se como sendo um trecho com caracter?sticas compartilhadas por outras ?reas de registros da fibropapilomatose e com fatores que podem ter contribu?do para o aumento dos registros de animais acometidos. Por se tratar de uma doen?a debilitante, que acomete principalmente animais juvenis e com etiologia ainda n?o bem definida, a fibropapilomatose impulsiona pesquisas que visam melhor entendimento da doen?a para conserva??o das esp?cies de tartarugas marinhas. / The five species of sea turtles that occur in the brazilian coast are classified as species at risk of extinction by global lists of threatened species. Such status is due to the different threats that these animals have suffered over the past decades, among them the destruction of natural habitat, fotopolui??o, incidental fishing, vehicle traffic and predation of eggs. Another significant threat to these animals, described in the literature, is the occurrence of fibropapillomatosis. This disease affects sea turtles, especially juveniles of the species Chelonia mydas, although it was also described in other species. This work intends to investigate the spatial and temporal distribution of records of sea turtles with fibropapilamatose stranding, living or dead, from the beaches of the municipalities of Icapu? / CE by Cai?ara do Norte / RN, and to characterize the histology of these lesions. For this daily monitoring were performed, using quads in order to record the occurrence of sea turtles in the Bacia Potiguar RN / CE of beaches. Dead animals, depending of the decomposition state, they were evaluated for the type, number and positioning of tumors, photographed and georeferenced. The live animals were rescued and translocated to the rehabilitation base of the project Cet?ceos da Costa Branca / UERN-Areia Branca where we performed the count procedure and location of the tumors. For the development of the research are being used data collected between 2011 and 2015. Among the 3.960 stranded sea turtles, 680 had tumors caused by fibropapillomatosis, values which grew during the years studied. In relation to the variation between the monitored sectors, the highest frequency of animals affected by the disease was recorded in the sector ?C? "Guamar?-Macau." As the development phase, most of the affected individuals were in the immature stage, but there were also adult animals record and subadult affected by the disease. The lesions are configured for presenting papillary projections and epidermal hyperplasia, hyperkeratinisation regions within the connective tissue and points with suggestive of inflammation erythrocyte clusters. In addition, we observed parasites and leech eggs present within tumor structure. The Bacia Potiguar RN / CE has been shown to be an excerpt with features shared by other areas of fibropapillomatosis occurrence and with factors that may have contributed to the increase of the records of affected animals. Because it is a debilitating disease, which affects mainly juvenile animals with etiology not yet well defined, fibropapillomatosis promotes research aimed at a better understanding of the disease for the conservation of sea turtle species.
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Herbivore and Nutrient Impact on Primary Producer Assemblages in a Tropical Marine EnvironmentLacey, Elizabeth 01 January 2012 (has links)
Globally, human populations are increasing and coastal ecosystems are becoming increasingly impacted by anthropogenic stressors. As eutrophication and exploitation of coastal resources increases, primary producer response to these drivers becomes a key indicator of ecosystem stability. Despite the importance of monitoring primary producers such as seagrasses and macroalgae, detailed studies on the response of these benthic habitat components to drivers remain relatively sparse.
Utilizing a multi-faceted examination of turtle-seagrass and sea urchin-macroalgae consumer and nutrient dynamics, I elucidate the impact of these drivers in Akumal, Quintana Roo, Mexico. In Yal Ku Lagoon, macroalgae bioindicators signified high nutrient availability, which is important for further studies, but did not consistently follow published trends reflecting decreased δ15N content with distance from suspected source. In Akumal Bay, eutrophication and grazing by turtles and fishes combine to structure patches within the seagrass beds. Grazed seagrass patches had higher structural complexity and productivity than patches continually grazed by turtles and fishes. Results from this study indicate that patch abandonment may follow giving-up density theory, the first to be recorded in the marine environment. As Diadema antillarum populations recover after their massive mortality thirty years ago, the role these echinoids will have in reducing macroalgae cover and altering ecosystem state remains to be clear. Although Diadema antillarum densities within the coral reef ecosystem were comparable to other regions within the Caribbean, the echinoid population in Akumal Bay was an insufficient driver to prevent dominance of a turf-algal-sediment (TAS) state. After a four year study, declining coral cover coupled with increased algal cover suggests that the TAS-dominated state is likely to persist over time despite echinoid recovery. Studies on macroalgal diversity and nutrients within this same region of echinoids indicated diversity and nutrient content of macroalgae increased, which may further increase the persistence of the algal-dominated state.
This study provides valuable insight into the variable effects of herbivores and nutrients on primary producers within a tropical coastal ecosystem. Results from this work challenge many of the currently accepted theories on primary producer response to nutrients and herbivory while providing a framework for further studies into these dynamics.
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USE OF STABLE ISOTOPES TO INFER FORAGING NICHE IN TWO MARINE TURTLE SPECIES: CHELONIA MYDAS AND ERETMOCHELYS IMBRICATAUnknown Date (has links)
Stable isotope analysis is a powerful tool that can be used to describe a population’s foraging niche by identifying basal resource use, trophic feeding levels, environmental stability, seasonal ecological variation, important shifts in life history, ontogenetic shifts, intraspecific habitat use, and population dynamics. Describing these relationships in endangered marine turtle populations and their critical foraging grounds is essential for determining informed management decisions. This study systematically describes the foraging niche of hawksbills Eretmochelys imbricata, and green turtles, Chelonia mydas in Buck Island Reef National Monument, U.S. Virgin Islands, a critical habitat for nesting and foraging. It assesses the relationships within and between the species in terms of overlap, annual and seasonal variation, and life history and feeding strategies within the community. Most importantly it describes these relationships with metrics that can be used in global comparisons or to measure change in local conditions. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
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Juvenile Green Turtle (chelonia Mydas) Foraging Ecology:feeding Selectivity And Forage Nutrient AnalysisGilbert, Eliza 01 January 2005 (has links)
For the endangered green turtle, Chelonia mydas, a fundamental component of recovery and conservation is an understanding of its foraging ecology. Foraging optimality models suggest animals will select resources of high quality over those of low quality. For green turtles, this behavior is important, as sufficient quantities of nutritionally adequate forage items are necessary for growth and reproduction. One intrinsic element in the understanding of green turtle foraging ecology is to identify and document the availability and quality of forage resources preferred by green turtles. The objectives of this study were: 1) determine whether juvenile green turtles showed a feeding preference by comparing prey items in the diet to the availability of those items in the habitat, 2) identify species for which there was selection or avoidance, 3) identify nutritional factors determining selection or avoidance of prey items, and 4) evaluate the nutritional content of the diet. This research was conducted by comparing lavage samples from juvenile green turtles to samples from benthic surveys within the habitat. To determine feeding preference, Ivlev's Electivity Index was used to compare ingested species of algae with those available in the habitat. Nutritional analysis of forage was conducted to identify possible nutrients relating to feeding preference. Juvenile green turtles selectively foraged on Chlorophyta and Rhodophyta. Results indicate that diet selection was based on nutritional content. Both the composite diet and the main diet item, Hypnea spp, had a higher gross energy value, were higher in protein, and lower in fiber than prey items that were avoided. Conservation of green turtles requires effective habitat management, which must be informed by an understanding and evaluation of the habitat. For juvenile green turtles, this study indicates that habitats dominated by Chlorophyta and Rhodophyta may be more important for the health of green turtle populations than habitats dominated by Phaeophyta.
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