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Análise da atividade de leucócitos e de bifenilas policloradas aplicada ao estudo da fibropapilomatose em Chelonia mydas (Testudines, Cheloniidae) (Linnaeus 1758) / Analysis of leukocyte activity and polychlorinated biphenyls applied to the study of fibropapillomatosis in Chelonia mydas (Testudines, Cheloniidae) (Linnaeus 1758)Rossi, Silmara 15 April 2014 (has links)
A tartaruga verde (Chelonia mydas) é uma tartaruga marinha que se alimenta e nidifica em locais da costa brasileira, ilhas e atóis. Esta espécie tem sido acometida pela fibropapilomatose (FP), doença considerada como uma das mais importantes ameaças à sua sobrevivência e caracterizada por tumores cutâneos benignos. A etiologia é multifatorial e complexa, possivelmente havendo relação entre Chelonid Fibropapilloma-associated Herpesvirus, fatores ambientais e genéticos. Foram estudadas 133 tartarugas verdes com e sem tumores provenientes de cinco áreas brasileiras: Florianópolis/SC, Ubatuba/SP, Vitória/ES, Almofala/CE e Fernando de Noronha/PE. Foram obtidos dados de biometria (comprimento curvilíneo da carapaça-CCC, massa corporal-MC e índice de condição corporal-ICC), tamanho (classificado por categorias A, B, C e D), quantidade e localização anatômica dos tumores, além da colheita de amostra sanguínea. Os objetivos foram (1) avaliar a atividade dos leucócitos por citometria de fluxo (fagocitose e burst oxidativo); (2) investigar a presença de sete congêneres de bifenilas policloradas (PCBs) e (3) estabelecer correlações entre PCBs e a atividade dos leucócitos. Houve diferenças no CCC entre tartarugas sem tumores de acordo com a área de estudo, na MC e no ICC entre animais acometidos ou não capturados em Ubatuba. Foram quantificados e classificados 1033 tumores de 50 tartarugas verdes, sendo que a quantidade por tartaruga variou de 1 a 61 e a maior parte foi classificada nas categorias de tamanho A (446 tumores) e B (520 tumores) e na região anterior (669 tumores). Foi observada diferença significativa nas concentrações do congênere PCB 138 entre tartarugas com e sem FP capturadas em Vitória. Animais acometidos tiveram maiores concentrações de todas as PCBs quantificadas, exceto as tartarugas verdes capturadas em Vitória no caso dos congêneres PCBs 118, 138, 153 e 180. PCB 138 foi quantificado em maior concentração nas amostras e PCB 180 em níveis menores. Não foram observadas correlações significativas entre concentrações de PCBs e atividade celular. A FP tem sido amplamente pesquisada e os estudos que visam estabelecer correlações entre poluentes químicos e saúde animal são extremamente importantes, pois podem contribuir para novas direções nos planos de ação para conservação. / The green sea turtle (Chelonia mydas) feeds and nests in Brazilian coast, islands and atolls. This species has been affected by fibropapillomatosis (FP), disease considered one of the most important threats to its survival and characterized by benign skin tumors. The etiology is multifactorial and complex, possibly having relation between Chelonid Fibropapilloma-associated Herpesvirus, environmental and genetic factors. Were studied 133 green sea turtles with and without FP from five Brazilian areas: Florianópolis/SC, Ubatuba/SP, Vitória/ES, Almofala/CE and Fernando de Noronha/PE. Were taken biometric data (curved carapace length-CCL, body mass-BM and body condition index-BCI), as well as size (classified by categories A, B, C and D), numbers and anatomical distribution of tumors, besides blood sample collection. The aims were (1) to assess leukocytes activity by flow cytometry (phagocytosis and oxidative burst); (2) to investigate the presence of seven congeners of polychlorinated biphenyls (PCBs) and (3) to establish correlations between PCBs and leukocytes activity. There were differences in CCL between turtles without FP according to the study area, in BM and BCI between affected and non-affected animals caught in Ubatuba. Were quantified and classified 1033 tumors of 50 green sea turtles, the number of tumors ranged from 1 to 61 and the most part of them was classified in categories of size A (446 tumors) and B (520 tumors) and in anterior region (669 tumors). Was observed difference in PCB 138 concentrations between green sea turtle with and without FP caught in Vitória. Affected animals had higher concentrations of all PCBs quantified, except green sea turtles caught in Vitória in the event of PCBs 118, 138, 153 and 180. Were quantified highest concentrations of PCB 138 and lowest of PCB 180. There were not significant correlations between PCBs concentration and leukocyte activity. The FP has been widely investigate and the studies that aimed to establish correlations between pollutants and animal health are very important, because can contribute for new directions in sea turtle conservation issues.
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Educational techniques that foster creative solutions and good data in field biology: examples from 3 continentsMadden, Derek 01 1900 (has links)
One of the principles regarding our knowledge about life on earth is that no organism can be fully understood without taking into account its surrounding environment. This study examines the extent to which ecosystem-focused field studies may be associated with students' academic performance and potential to contribute to the advancement of science and conservation. Pilot studies conducted in Panama and California established methods used in this project from 1993-2003. Two hundred and sixty-seven students conducted field studies in either Kenya or Costa Rica. Students worked in cognitive apprenticeships, in which research staff trained each student to conduct field research. At the conclusion of their fieldwork, the research staff assessed the students written field reports. The students' reports were then sorted according to the extent to which their studies were ecosystem-focused. Data analysis through nonparametric, Kruskal-Wallis statistical tests revealed no significant difference in academic performance on field study reports, in regards to whether the studies were narrow in scope (species-specific) or broad (ecosystem-focused). Marginal significance was revealed between ecosystem-focused studies and the potential for students' fieldwork to contribute to the advancement of science and conservation. Also addressed in the data were injuries, disease, and potential hazards, which were influenced by prudent and decisive leadership. Successful field studies require consideration of the content, context, and design of the intended field projects. Many of the solutions to environmental problems on the planet will come from the working hands of teachers and students that conduct explorations in the field. / Life Sciences in Education / D. Phil. (Mathematics, Science and Technology Education)
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Análise da atividade de leucócitos e de bifenilas policloradas aplicada ao estudo da fibropapilomatose em Chelonia mydas (Testudines, Cheloniidae) (Linnaeus 1758) / Analysis of leukocyte activity and polychlorinated biphenyls applied to the study of fibropapillomatosis in Chelonia mydas (Testudines, Cheloniidae) (Linnaeus 1758)Silmara Rossi 15 April 2014 (has links)
A tartaruga verde (Chelonia mydas) é uma tartaruga marinha que se alimenta e nidifica em locais da costa brasileira, ilhas e atóis. Esta espécie tem sido acometida pela fibropapilomatose (FP), doença considerada como uma das mais importantes ameaças à sua sobrevivência e caracterizada por tumores cutâneos benignos. A etiologia é multifatorial e complexa, possivelmente havendo relação entre Chelonid Fibropapilloma-associated Herpesvirus, fatores ambientais e genéticos. Foram estudadas 133 tartarugas verdes com e sem tumores provenientes de cinco áreas brasileiras: Florianópolis/SC, Ubatuba/SP, Vitória/ES, Almofala/CE e Fernando de Noronha/PE. Foram obtidos dados de biometria (comprimento curvilíneo da carapaça-CCC, massa corporal-MC e índice de condição corporal-ICC), tamanho (classificado por categorias A, B, C e D), quantidade e localização anatômica dos tumores, além da colheita de amostra sanguínea. Os objetivos foram (1) avaliar a atividade dos leucócitos por citometria de fluxo (fagocitose e burst oxidativo); (2) investigar a presença de sete congêneres de bifenilas policloradas (PCBs) e (3) estabelecer correlações entre PCBs e a atividade dos leucócitos. Houve diferenças no CCC entre tartarugas sem tumores de acordo com a área de estudo, na MC e no ICC entre animais acometidos ou não capturados em Ubatuba. Foram quantificados e classificados 1033 tumores de 50 tartarugas verdes, sendo que a quantidade por tartaruga variou de 1 a 61 e a maior parte foi classificada nas categorias de tamanho A (446 tumores) e B (520 tumores) e na região anterior (669 tumores). Foi observada diferença significativa nas concentrações do congênere PCB 138 entre tartarugas com e sem FP capturadas em Vitória. Animais acometidos tiveram maiores concentrações de todas as PCBs quantificadas, exceto as tartarugas verdes capturadas em Vitória no caso dos congêneres PCBs 118, 138, 153 e 180. PCB 138 foi quantificado em maior concentração nas amostras e PCB 180 em níveis menores. Não foram observadas correlações significativas entre concentrações de PCBs e atividade celular. A FP tem sido amplamente pesquisada e os estudos que visam estabelecer correlações entre poluentes químicos e saúde animal são extremamente importantes, pois podem contribuir para novas direções nos planos de ação para conservação. / The green sea turtle (Chelonia mydas) feeds and nests in Brazilian coast, islands and atolls. This species has been affected by fibropapillomatosis (FP), disease considered one of the most important threats to its survival and characterized by benign skin tumors. The etiology is multifactorial and complex, possibly having relation between Chelonid Fibropapilloma-associated Herpesvirus, environmental and genetic factors. Were studied 133 green sea turtles with and without FP from five Brazilian areas: Florianópolis/SC, Ubatuba/SP, Vitória/ES, Almofala/CE and Fernando de Noronha/PE. Were taken biometric data (curved carapace length-CCL, body mass-BM and body condition index-BCI), as well as size (classified by categories A, B, C and D), numbers and anatomical distribution of tumors, besides blood sample collection. The aims were (1) to assess leukocytes activity by flow cytometry (phagocytosis and oxidative burst); (2) to investigate the presence of seven congeners of polychlorinated biphenyls (PCBs) and (3) to establish correlations between PCBs and leukocytes activity. There were differences in CCL between turtles without FP according to the study area, in BM and BCI between affected and non-affected animals caught in Ubatuba. Were quantified and classified 1033 tumors of 50 green sea turtles, the number of tumors ranged from 1 to 61 and the most part of them was classified in categories of size A (446 tumors) and B (520 tumors) and in anterior region (669 tumors). Was observed difference in PCB 138 concentrations between green sea turtle with and without FP caught in Vitória. Affected animals had higher concentrations of all PCBs quantified, except green sea turtles caught in Vitória in the event of PCBs 118, 138, 153 and 180. Were quantified highest concentrations of PCB 138 and lowest of PCB 180. There were not significant correlations between PCBs concentration and leukocyte activity. The FP has been widely investigate and the studies that aimed to establish correlations between pollutants and animal health are very important, because can contribute for new directions in sea turtle conservation issues.
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Beach Nourishment: Effects on the Hatching & Emergence Success Rates of Leatherback (Dermochelys coriacea), Loggerhead (Caretta caretta), and Green (Chelonia mydas) Sea TurtlesCaderas, Jenna 01 July 2016 (has links)
Broward County, Florida is a popular tourism destination. Due to its popularity, much of the shoreline has been modified and natural habitats were replaced with infrastructure such as houses, condominiums, resorts, and restaurants. The same Broward County beaches utilized by tourists and residents are important for three species of nesting sea turtles, including the Leatherback, Dermochelys coriacea, Loggerhead, Caretta caretta, and Green, Chelonia mydas, Turtles. The Broward County Sea Turtle Conservation Program (BCSTCP) collects yearly data in order to study these endangered reptiles. Increased anthropogenic effects including further coastal development (public & private), public beach events, public beach access, as well as natural events, have caused these important nesting beaches to erode and narrow. In an effort to control this erosion damage, Broward County has performed a number of beach nourishment projects. This study found yearly fluctuations in sea turtle hatching and emergence success rates, and years of beach nourishment projects significantly decreased these rates. Yearly hatching data available from Broward County concludes that beach nourishment, as well as hurricanes and tropical storms cause decreases in sea turtle hatching and emergence success rates in Broward County. Additionally, nest depth and sea turtle size increases the hatching and emergence success rates from females that are not too large or too small that nest in Broward County.
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Ecology of marine turtles under climate changeStokes, Kimberley Laura January 2014 (has links)
Climate change threatens to disrupt biological systems around the globe, sparking debate over natural capacity for adaptation in a fragmented landscape. Marine turtles are evolutionarily ancient and have survived millions of years of prehistoric climate change, but are threatened by the rapidity of modern warming and a history of severe overexploitation that has left most populations depleted. This thesis explores a nesting aggregation of the green turtle (Chelonia mydas) in northern Cyprus, where a longitudinal programme of both intensive and extensive monitoring enables insight into individual and population level parameters and processes. Nesting on the two coastlines covered by this project is in the early stages of recovery, possibly in response to exhaustive nest protection efforts over the last twenty years. Saturation tagging at one key site allows us to confirm that recruitment of new breeders is an important driver of this trend, and that average clutch frequency has remained stable around three nests per female per year, validating nest-count derived abundance estimates at a regional scale. Concern has been raised, however, regarding recent changes in fishing practices which are impacting the local juvenile neritic phase, which may have a lagged effect on the recovery of this nesting population. A collaborative tracking effort including all other countries with major nesting in the Mediterranean allows us to identify major foraging grounds for this species, with two hotspots accounting for >50% of tracked individuals, as well as coastal and pelagic seasonal corridors of high use. Bycatch levels and mortality rates for turtles in these key areas are largely unknown and should be prioritised for investigation. Hatchling sex ratios from the main study beach are extremely female-biased (estimated 97% female for the twenty year period 1993-2012). A 1oC rise in average incubation temperatures threatens near complete hatchling feminisation on this beach, whilst a 2oC rise could reduce hatch success to less than 50%. Thermal effects on hatchling morphometrics are evident, with a 1oC rise in temperature reducing average length, width and weight by 1%, 2% and 3% respectively. More favourable incubation conditions were found early in the season, in deeper nests laid by larger females, and on beaches of lighter sand. In contrast, adult sex ratios at the main site are male-biased, posing questions regarding sex-specific survival rates and optimal hatchling sex ratios. A phenological shift towards earlier nesting is demonstrated for the first time in this species, and could potentially ameliorate warming effects. Carry-over climate forcing effects from the foraging ground influence the breeding frequency of individuals, driving population level responses in annual magnitude of nesting. This work emphasises the utility and necessity of long-term individual-based monitoring programmes in elucidating population trends and climate responses in iteroparous species with non-annual breeding.
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<b>Clutch success and innovative satellite tracking of leatherback sea turtles on Bioko Island,</b><b>Equatorial Guinea</b>Trevor L Proctor (18423216) 22 April 2024 (has links)
<p dir="ltr">The Leatherback Sea Turtle (<i>Dermochelys coriacea</i>) is a globally vulnerable species suffering from declining populations due to anthropogenic pressures. There are seven recognized Leatherback Sea Turtle regional management units; however, the Southeast Atlantic unit is considered data deficient. Bioko Island, Equatorial Guinea, is a primary nesting rookery for the Southeast Atlantic regional management unit and has some of the world’s highest numbers of nesting Leatherback Sea Turtles. Despite Bioko Island’s importance to the species, little is known about the nesting ecology or post-nesting migratory movement and behaviors of its nesting Leatherback Sea Turtles. Here, I present the findings of two individual research projects on the nesting ecology of Leatherback Sea Turtles on Bioko Island. First, I explored the long-term clutch success rates (i.e., hatching success and emergence success) of <i>in situ</i> Leatherback Sea Turtle nests on Bioko and searched for associated variables. I found significant spatiotemporal variation over nine nesting seasons, likely driven by individual beach characteristics rather than regional climate patterns. Secondly, I described a novel effort to use solar-reliant towable transmitters to track the post-nesting migratory movements and behaviors of Leatherback Sea Turtles nesting on Bioko Island. With the results from each project, I make recommendations to further the current conservation and research initiatives of Leatherback Sea Turtles.</p>
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DEPREDATION OF OLIVE RIDLEY AND LOGGERHEAD TURTLE CLUTCHES ON BEACHES WITH AND WITHOUT PREDATOR MANAGEMNTCarlynn Nicole Cornhill (11002167) 23 July 2021 (has links)
<p>Management of predation on sea
turtle nesting beaches is vital to conservation efforts for the vulnerable
loggerhead turtles (<i>Caretta caretta</i>) and olive ridley turtles (<i>Lepidochelys
olivacea</i>). Sea turtles increasingly face threats from invasive and
human-tolerant mammalian predators as human disturbances on nesting beaches rises.
The intensity of mammalian predation has increased in Las Baulas National Park
in Costa Rica which is an important nesting site for several species of
threatened and endangered sea turtles. I analyzed loggerhead and olive ridley
nest predation on four beaches in the United States and Costa Rica that were
chosen for variations in degree of human disturbance and management strategies.
My objectives were to 1) determine if egg predation rates differ at the four
sites, 2) determine the most destructive predators at each location, and 3)
suggest management options to alleviate mammalian threats to turtle clutches on
Playa Grande and Playa Cabuyal in Costa Rica. My results show that the beaches
without a nest protection or predator control program had very high rates of predation.
Invasive mammalian predators and mammalian predators associated with human disturbance
were the most destructive at the four sites. I recommend that regulations
regarding dogs and the take of eggs from the beach are enforced at Playa
Cabuyal and that physical nest protection is rapidly implemented at Playa
Grande. I also recommend that the National Park consider managing raccoon
predation by removing problem individuals, but caution that they do so in a way
that maintains the animals’ role in the ecosystem.</p>
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Factors influencing Kemp's ridley sea turtle (Lepidochelys kempii) distribution in nearshore waters and implications for managementMetz, Tasha Lynn 15 November 2004 (has links)
Post-pelagic juvenile and subadult Kemp's ridley sea turtles (Lepidochelys kempii) (20-40 cm straight carapace length) utilize nearshore waters of the northwestern Gulf of Mexico as nursery or developmental feeding grounds. This study utilizes 10 years of entanglement netting data to characterize long-term abundance and distribution of Kemp's ridley sea turtles at index habitats in this region. Netting surveys were conducted during April-October 1993-2002, primarily at Sabine Pass, Texas and Calcasieu Pass, Louisiana. Additionally, this study takes an ecosystem-based approach to understanding factors influencing Kemp's ridley in-water abundance and distribution via the development of a conceptual model incorporating data on nesting dynamics, environmental conditions, prey availability, and predation pressure.
Overall monthly mean ridley catch-per-unit-effort (CPUE) peaked in the beginning of summer (April-June), probably in response to rising water temperatures and seasonal occurrence of blue crab prey. Annual mean ridley CPUE across all study areas peaked in 1994, 1997, 1999 and 2002, suggesting a 2-3 year cycle in abundance that may be related to patterns in clutch size or hatch success at the Rancho Nuevo, Mexico nesting beach. However, ridley CPUE in nearshore waters remained relatively constant or decreased slightly even as number of hatchlings released from Rancho Nuevo increased exponentially. Annual declines in Texas strandings since 1994 and subsequent increases in Florida counterparts since 1995 suggest a shift in ridley distribution from the western to eastern Gulf in recent years.
Significant declines in ridley CPUE at Sabine Pass since 1997 coincided with a concurrent reduction in blue crab size, but a similar trend was not detected at Calcasieu Pass. Kemp's ridley occurrence at study sites was not significantly related to shrimping activity/by-catch. There also were no biologically significant relationships between Kemp's ridley CPUE and abiotic factors, nor were ridleys deterred from utilizing areas frequented by bull sharks. Overall, nesting dynamics and prey availability were conceptual model components appearing to have the greatest influence on nearshore ridley occurrence.
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Environmental Factors Affecting Loggerhead Sea Turtle (Caretta caretta) Nesting, Hatching, and Incubation Patterns in Broward County, FloridaBest, Zoey Ellen 28 April 2017 (has links)
Reproductive success in loggerhead (Caretta caretta) sea turtles is strongly dependent on the effective placement and internal conditions of their nests. Embryos rely on optimal incubation conditions for proper development and growth, which determines how many hatchlings will emerge from the nest. The internal microclimate of each nest is delicately balanced and can be easily influenced by external environmental conditions. This study was designed to examine several environmental variables and determine their effects on sea turtle nesting numbers, hatching success, and incubation conditions in Broward County Florida. Over a span of 25 years (1991-2015), the Broward County Sea Turtle Conservation Program has collected data on each sea turtle nest laid in Broward County. This data was analyzed and plotted to visualize nesting and hatching trends, and regressions were fitted to make comparisons to historic air temperature, sea surface temperature, precipitation, and lunar illumination data. These regressions were tested for significance, and each environmental variable was found to have varying levels of impact on sea turtle nesting and hatching behavior. Of the environmental variables considered in this study, analyses suggest that sea turtles are most responsive to temperature, with sea surface temperature serving as the best proxy for predicting nesting behaviors. Air temperature over the incubation period was found to be the best indicator for hatch success percentage. Air temperature, sea surface temperature, and precipitation averages all significantly affected the length of the incubation period. The regression models created in this study could be used to examine the interactions between climatic variables, and to indicate what impacts can be expected by these various environmental factors. This information could be used to estimate the future effects of climate change on sea turtle reproduction, and to predict general reproductive success and future population trends.
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Advances in identifying archaeological traces of horn and other keratinous hard tissuesO'Connor, Sonia A., Solazzo, C., Collins, M. 2014 June 1923 (has links)
No / Despite being widely utilized in the production of cultural objects, keratinous hard tissues, such as horn, baleen, and tortoiseshell, rarely survive in archaeological contexts unless factors combine to inhibit biodeterioration. Even when these materials do survive, working, use, and diagenetic changes combine to make identification difficult. This paper reviews the chemistry and deterioration of keratin and past approaches to the identification of keratinous archaeological remains. It describes the formation of horn, hoof, baleen, and tortoiseshell and demonstrates how identification can be achieved by combining visual observation under low-power magnification with an understanding of the structure and characteristic deterioration of these materials. It also demonstrates how peptide mass fingerprinting of the keratin can be used to identify keratinous tissues, often to species, even when recognizable structural information has not survived.
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