As tartarugas marinhas são animais de vida longa, com maturação sexual tardia, grandes áreas de vida e ampla distribuição geográfica. Sofrem diversos impactos ao longo de seu ciclo de vida, o que contribui para estarem globalmente ameaçadas de extinção. Estes animais apresentam um ciclo de vida complexo, que consiste de estágios de desenvolvimento segregados espacialmente e temporalmente, envolvendo mudanças marcantes de habitat e dieta. O litoral sul do Brasil não apresenta áreas próprias para a desova de tartarugas marinhas, mas é utilizado regularmente por algumas espécies como área de alimentação, pelo menos em alguma etapa do seu desenvolvimento. As espécies registradas com mais frequência na região e analisadas neste estudo são a tartaruga-cabeçuda, Caretta caretta, e a tartaruga-verde, Chelonia mydas. Apesar de serem animais ameaçados de extinção, diversos aspectos do ciclo de vida das tartarugas marinhas permanecem pouco conhecidos. Idade e crescimento são parâmetros importantes para o melhor entendimento da história de vida das espécies e elaboração de estratégias de manejo. Espécimes encontrados encalhados mortos durante um período de 16 anos na costa do Rio Grande do Sul foram utilizados para realizar estimativas de idade e crescimento através de esqueletocronologia. Esta técnica oferece o potencial para uma rápida e ampla caracterização de parâmetros de idade e crescimento de uma população. Os resultados mostram que ambas as espécies são encontradas nesta região durante a fase juvenil, logo após o recrutamento do ambiente oceânico para o ambiente nerítico, que ocorre por volta de 12 anos e comprimentos de carapaça maiores que 55 cm nas tartarugas-cabeçudas e aproximadamente 30 cm e 3 anos nas tartarugas-verdes. As tartarugas-cabeçudas analisadas tiveram idades estimadas entre 10 e 29 anos e comprimentos da carapaça entre 53 e 101 cm e as tartarugas-verdes apresentaram entre 2 e 13 anos e tamanhos entre 31 e 62 cm. Taxas de crescimento são inversamente relacionadas à idade e ao tamanho, apresentando grande variação individual. Os resultados corroboram a ideia de que o litoral sul do Brasil é uma importante área de desenvolvimento para juvenis neríticos das duas espécies em questão, sendo uma região de extrema importância para a conservação das tartarugas marinhas no Atlântico sul ocidental. / Sea turtles are long-lived marine reptiles with late sexual mature, large home-ranges and wide geographic distribution. They are exposed to many impacts over its life cycle which contributes to their worldwide threatened status. Sea turtles present a complex life cycle of development stages that are segregated spatially and temporally involving marked changes in diet and habitat. The south coast of Brazil don‟t present nesting areas but is used by some species as feeding area at least in any stage of its development. The most abundant species in this region and the turtles analyzed in this study are the loggerhead and the green turtle. Although threatened worldwide, many aspects of life cycle of sea turtles remain poorly known. Age and growth are important parameters to understand life history and to develop management strategies. Specimens stranded during a period of 16 years along the coast of the State of Rio Grande do Sul were used to estimate age and growth by skeletochronology. This technique offers the potential to a quick and wide characterization of age and growth parameters of a population. The results show that both species live in this region during juvenile stage, just after recruitment from the oceanic environment to the neritic environment. The recruitment occurs about 12 years and length greater than 55 cm on loggerhead and from 30 cm and 3 years on green turtles. The loggerhead turtles have estimated age between 10 and 29 years and carapace length between 53 and 101 cm and green turtles presents between 2 and 13 years and length between 31 and 62 cm. Growth rates were inversely related to length and age. The results corroborate the idea that the south Brazilian coast is an important development area to neritic juveniles of both species, being a region of extreme importance to sea turtle conservation in the southwestern Atlantic.

As tartarugas marinhas são animais de vida longa, com maturação sexual tardia, grandes áreas de vida e ampla distribuição geográfica. Sofrem diversos impactos ao longo de seu ciclo de vida, o que contribui para estarem globalmente ameaçadas de extinção. Estes animais apresentam um ciclo de vida complexo, que consiste de estágios de desenvolvimento segregados espacialmente e temporalmente, envolvendo mudanças marcantes de habitat e dieta. O litoral sul do Brasil não apresenta áreas próprias para a desova de tartarugas marinhas, mas é utilizado regularmente por algumas espécies como área de alimentação, pelo menos em alguma etapa do seu desenvolvimento. As espécies registradas com mais frequência na região e analisadas neste estudo são a tartaruga-cabeçuda, Caretta caretta, e a tartaruga-verde, Chelonia mydas. Apesar de serem animais ameaçados de extinção, diversos aspectos do ciclo de vida das tartarugas marinhas permanecem pouco conhecidos. Idade e crescimento são parâmetros importantes para o melhor entendimento da história de vida das espécies e elaboração de estratégias de manejo. Espécimes encontrados encalhados mortos durante um período de 16 anos na costa do Rio Grande do Sul foram utilizados para realizar estimativas de idade e crescimento através de esqueletocronologia. Esta técnica oferece o potencial para uma rápida e ampla caracterização de parâmetros de idade e crescimento de uma população. Os resultados mostram que ambas as espécies são encontradas nesta região durante a fase juvenil, logo após o recrutamento do ambiente oceânico para o ambiente nerítico, que ocorre por volta de 12 anos e comprimentos de carapaça maiores que 55 cm nas tartarugas-cabeçudas e aproximadamente 30 cm e 3 anos nas tartarugas-verdes. As tartarugas-cabeçudas analisadas tiveram idades estimadas entre 10 e 29 anos e comprimentos da carapaça entre 53 e 101 cm e as tartarugas-verdes apresentaram entre 2 e 13 anos e tamanhos entre 31 e 62 cm. Taxas de crescimento são inversamente relacionadas à idade e ao tamanho, apresentando grande variação individual. Os resultados corroboram a ideia de que o litoral sul do Brasil é uma importante área de desenvolvimento para juvenis neríticos das duas espécies em questão, sendo uma região de extrema importância para a conservação das tartarugas marinhas no Atlântico sul ocidental. / Sea turtles are long-lived marine reptiles with late sexual mature, large home-ranges and wide geographic distribution. They are exposed to many impacts over its life cycle which contributes to their worldwide threatened status. Sea turtles present a complex life cycle of development stages that are segregated spatially and temporally involving marked changes in diet and habitat. The south coast of Brazil don‟t present nesting areas but is used by some species as feeding area at least in any stage of its development. The most abundant species in this region and the turtles analyzed in this study are the loggerhead and the green turtle. Although threatened worldwide, many aspects of life cycle of sea turtles remain poorly known. Age and growth are important parameters to understand life history and to develop management strategies. Specimens stranded during a period of 16 years along the coast of the State of Rio Grande do Sul were used to estimate age and growth by skeletochronology. This technique offers the potential to a quick and wide characterization of age and growth parameters of a population. The results show that both species live in this region during juvenile stage, just after recruitment from the oceanic environment to the neritic environment. The recruitment occurs about 12 years and length greater than 55 cm on loggerhead and from 30 cm and 3 years on green turtles. The loggerhead turtles have estimated age between 10 and 29 years and carapace length between 53 and 101 cm and green turtles presents between 2 and 13 years and length between 31 and 62 cm. Growth rates were inversely related to length and age. The results corroborate the idea that the south Brazilian coast is an important development area to neritic juveniles of both species, being a region of extreme importance to sea turtle conservation in the southwestern Atlantic.

As tartarugas marinhas são animais de vida longa, com maturação sexual tardia, grandes áreas de vida e ampla distribuição geográfica. Sofrem diversos impactos ao longo de seu ciclo de vida, o que contribui para estarem globalmente ameaçadas de extinção. Estes animais apresentam um ciclo de vida complexo, que consiste de estágios de desenvolvimento segregados espacialmente e temporalmente, envolvendo mudanças marcantes de habitat e dieta. O litoral sul do Brasil não apresenta áreas próprias para a desova de tartarugas marinhas, mas é utilizado regularmente por algumas espécies como área de alimentação, pelo menos em alguma etapa do seu desenvolvimento. As espécies registradas com mais frequência na região e analisadas neste estudo são a tartaruga-cabeçuda, Caretta caretta, e a tartaruga-verde, Chelonia mydas. Apesar de serem animais ameaçados de extinção, diversos aspectos do ciclo de vida das tartarugas marinhas permanecem pouco conhecidos. Idade e crescimento são parâmetros importantes para o melhor entendimento da história de vida das espécies e elaboração de estratégias de manejo. Espécimes encontrados encalhados mortos durante um período de 16 anos na costa do Rio Grande do Sul foram utilizados para realizar estimativas de idade e crescimento através de esqueletocronologia. Esta técnica oferece o potencial para uma rápida e ampla caracterização de parâmetros de idade e crescimento de uma população. Os resultados mostram que ambas as espécies são encontradas nesta região durante a fase juvenil, logo após o recrutamento do ambiente oceânico para o ambiente nerítico, que ocorre por volta de 12 anos e comprimentos de carapaça maiores que 55 cm nas tartarugas-cabeçudas e aproximadamente 30 cm e 3 anos nas tartarugas-verdes. As tartarugas-cabeçudas analisadas tiveram idades estimadas entre 10 e 29 anos e comprimentos da carapaça entre 53 e 101 cm e as tartarugas-verdes apresentaram entre 2 e 13 anos e tamanhos entre 31 e 62 cm. Taxas de crescimento são inversamente relacionadas à idade e ao tamanho, apresentando grande variação individual. Os resultados corroboram a ideia de que o litoral sul do Brasil é uma importante área de desenvolvimento para juvenis neríticos das duas espécies em questão, sendo uma região de extrema importância para a conservação das tartarugas marinhas no Atlântico sul ocidental. / Sea turtles are long-lived marine reptiles with late sexual mature, large home-ranges and wide geographic distribution. They are exposed to many impacts over its life cycle which contributes to their worldwide threatened status. Sea turtles present a complex life cycle of development stages that are segregated spatially and temporally involving marked changes in diet and habitat. The south coast of Brazil don‟t present nesting areas but is used by some species as feeding area at least in any stage of its development. The most abundant species in this region and the turtles analyzed in this study are the loggerhead and the green turtle. Although threatened worldwide, many aspects of life cycle of sea turtles remain poorly known. Age and growth are important parameters to understand life history and to develop management strategies. Specimens stranded during a period of 16 years along the coast of the State of Rio Grande do Sul were used to estimate age and growth by skeletochronology. This technique offers the potential to a quick and wide characterization of age and growth parameters of a population. The results show that both species live in this region during juvenile stage, just after recruitment from the oceanic environment to the neritic environment. The recruitment occurs about 12 years and length greater than 55 cm on loggerhead and from 30 cm and 3 years on green turtles. The loggerhead turtles have estimated age between 10 and 29 years and carapace length between 53 and 101 cm and green turtles presents between 2 and 13 years and length between 31 and 62 cm. Growth rates were inversely related to length and age. The results corroborate the idea that the south Brazilian coast is an important development area to neritic juveniles of both species, being a region of extreme importance to sea turtle conservation in the southwestern Atlantic.

Invasive fire ants are aggressive predators of ground nesting birds and reptiles and are spreading rapidly throughout tropical and temperate climates. Fire ants have been known to prey on a variety of reptile species, including threatened loggerhead sea turtles. The granular fire ant bait AMDRO® is being used on sea turtle nesting beaches to protect nests and hatchlings from these predators, however no studies have been conducted to thoroughly assess its effect on any reptile species. In this field study, I examined the impact of AMDRO® on hatching and emergence success, body condition, and orientation behavior in loggerhead sea turtles (Caretta caretta) in Juno Beach, Florida, USA. Pesticide granules were placed in a one-foot diameter circle directly above nest chambers during the final 5-10 days of incubation, which is representative of typical field applications of this pesticide on nesting beaches. Two controls were used in this study: cornmeal granules in soybean oil served as the vehicle control, and a second group of untreated control nests were left to incubate naturally, undisturbed. After a natural emergence, hatchlings were collected to calculate a body condition index (BCI). For a subset of the nests, 20 hatchlings were collected to perform orientation assays to assess the hatchlings’ ability to orient correctly toward the ocean, a visually mediated process that could be altered by visual impairments resulting from ADMRO® exposure. Three days following a mass emergence event, nests were excavated to collect hatching and emergence success data. Sand samples were collected to determine if the toxicant persisted in the environment or penetrated the egg chamber. Analyses indicated that the toxicant had no effect on hatchling morphology, hatching success, or emergence success. It also had no effect on the ability of hatchlings to orient toward the ocean. However, the pesticide granules attracted more predators than were seen at control nests. Thus, while AMDRO® might not directly impact reproductive success or hatchling behavior, it had the unanticipated effect of possibly increasing nest vulnerability to predators. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

The aims of this work are:1. To provide the normal cervical and coelomic radiographic appearance of the Loggerhead sea turtle, in the dorso-ventral view, as well as other useful landmarks, to allow for correlation of shell scutes with internal anatomic structures. 2. To provide the normal radiographic anatomy of the limbs of the Loggerhead sea turtle in combination with data obtained from computed tomography - osteological, gross anatomical and histological data.3. To describe the normal ultrasonographic appearance of cervical structures and coelomic organs of the Loggerhead sea turtle, and to provide the respective images of frozen cross-sections for anatomical reference.4. To provide normal computed tomographic images of the vertebral column and coelomic structures of the Loggerhead sea turtle, by establishing reference standards for organ size and position in this species; to provide images of virtual tracheo-bronchoscopy and 3D reconstructions of the respiratory tract and bone structures.5. To provide the normal magnetic resonance imaging (MRI) appearance of coelomic structures of Loggerhead sea turtles in T1 and T2-weighted scans via comparison with cross-sectional anatomic sections of this species.

The loggerhead sea turtle Caretta caretta is listed as threatened with extinction on the US Endangered Species Act. Those loggerhead turtles that nest on US beaches from North Carolina to north-east Florida are a genetically distinct subpopulation. This subpopulation is small, and may be declining. To obtain information about the migratory pathways of these turtles we tracked post-nesting movements of five females by satellite from their nesting beach at Wassaw Island, Georgia. Four turtles migrated north of the nesting beach, of which three moved to coastal waters of mid Atlantic states (total distances of 157-1,458 km). Efforts to reduce mortality of northern subpopulations of loggerhead turtles need to focus on identifying and reducing threats in north-east US waters.

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

Sea turtle hatchlings emerge from their nest and quickly crawl to the surf. During the crawl, hatchlings may encounter threats, biotic and abiotic, which can affect their ability to successfully reach the surf. The impact of these threats on hatchling survival during that crawl is largely undocumented. Current methods used to estimate cohort recruitment rely heavily on nest inventory data. This method, however, does not account for post-emergent hatchling mortality that occurs during the crawl. During the 2017-2018 nesting seasons, I quantified the fates of 1,379 loggerhead (Caretta caretta) hatchlings from 26 nest emergences during their crawl from the nest to the surf on the east and west coasts of Florida. I documented hatchling fates at 5 Florida nesting beaches: Wabasso, Boca Raton, Keewaydin Island, Naples, and Anna Maria Island. Overall, 6.5% of all emergent hatchlings died during the crawl from the nests to the surf. Ghost crabs, night herons, foxes, and coyotes killed hatchlings and photopollution and barriers on the beach (both abiotic threats) caused hatchling mortality. Anthropogenic (abiotic) threats accounted for more mortality than did predators. In order to assess how beach urbanization impacts hatchling mortality, I categorized each study site as urban (Wabasso and Naples), intermediate (Anna Maria Island and Boca Raton), or natural (Keewaydin Island) based on the relative levels of shoreline development and human activity at each beach. Sites with intermediate levels of urbanization accounted for greater levels of hatchling mortality than at other beaches due to the absolutely larger numbers of hatchlings lost to a disorientation event and to a beach barrier. Given the small numbers of emergences, at all sites, only a small proportion of the hatchlings mortalities (e.g., between 3 and 12 percent), site type could not be rigorously used as a discriminator. My results provide a better understanding of how specific environmental threats contribute to hatchling mortality. While nest-to-surf mortality is relatively low, its cumulative costs add up to several hundreds of thousands of hatchlings. Armed with this information, nesting beach managers can assess risks and focus their efforts to implement the most effective management practices to minimize losses of this imperiled species. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

Locomotion of animals, whether by running, flying, swimming or crawling, is crucial to their survival. The natural environments they encounter are complex containing fluid, solid or yielding substrates. These environments are often uneven and inclined, which can lead to slipping during footsteps presenting great locomotor challenges. Many animals have specialized appendages for locomotion allowing them to adapt to their environmental conditions. Aquatically adapted animals have fins and flippers to swim through the water, however, some species use their paddle-like appendages to walk on yielding terrestrial substrates like the beach. Beach sand, a granular medium, behaves like a solid or a fluid when stress is applied. Principles of legged locomotion on yielding substrates remain poorly understood, largely due to the lack of fundamental understanding of the complex interactions of body/limbs with these substrates on the level of the Navier-Stokes Equations for fluids. Understanding of the limb-ground interactions of aquatic animals that utilize terrestrial environments can be applied to the ecology and conservation of these species, as well as enhance construction of man-made devices. In this dissertation, we studied the locomotion of hatchling loggerhead sea turtles on granular media integrating biological, robotic, and physics studies to discover principles that govern fin and flipper locomotion on flowing/yielding media. Hatchlings in the field modified their limb use depending on substrate compaction. On soft sand they bent their wrist to utilize the solid features of sand, whereas on hard ground they used a rigid flipper and claw to clasp asperities during forward motion. A sea turtle inspired physical model in the laboratory was used to test detailed kinematics of fin and flipper locomotion on granular media. Coupling of adequate step distance, body lift and thrust generation allowed the robot to move successfully forward avoiding previously disturbed ground. A flat paddle intruder was used to imitate the animal's flipper in physics drag experiments to measure the forces during intrusion and thrust generation.

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós–Graduação em Oceanografia Biológica, Instituto de Oceanografia, 2010. / Submitted by Cristiane Gomides (cristiane_gomides@hotmail.com) on 2013-12-16T11:32:16Z No. of bitstreams: 1 Roberta Petitet (1) b.pdf: 1605550 bytes, checksum: 687c7fdc2f6fa13dece0188ce08db8b1 (MD5) / Approved for entry into archive by Sabrina Andrade (sabrinabeatriz@ibest.com.br) on 2013-12-18T18:19:54Z (GMT) No. of bitstreams: 1 Roberta Petitet (1) b.pdf: 1605550 bytes, checksum: 687c7fdc2f6fa13dece0188ce08db8b1 (MD5) / Made available in DSpace on 2013-12-18T18:19:54Z (GMT). No. of bitstreams: 1 Roberta Petitet (1) b.pdf: 1605550 bytes, checksum: 687c7fdc2f6fa13dece0188ce08db8b1 (MD5) Previous issue date: 2010 / A espécie de tartaruga marinha Caretta caretta (tartaruga-cabeçuda) utiliza a costa brasileira para desenvolvimento e reprodução, suas praias de desova estão situadas nos estados da Bahia e Espírito Santo. A maioria dos estudos sobre a tartaruga-cabeçuda no Brasil lidam com fêmeas adultas e os estágios de juvenis e sub-adultos são pouco conhecidos. O presente estudo faz uma estimativa da idade de tartarugas-cabeçudas através da técnica de esqueletocronologia por análises do úmero provenientes de ambos os estágios, nerítico e oceânico. E ajusta um modelo de crescimento para a população dessa espécie do Atlântico Sul Ocidental. Baseado na validação de que uma linha de crescimento corresponde a um ano, os números de linhas presentes no úmero correspondem a idade do animal. Para tartarugas de tamanho maior, foi aplicado o fator de correção para o cálculo de linhas perdidas devido à reabsorção óssea e perda das primeiras linhas de crescimento. Esse fator de correção foi baseado em dois modelos, o primeiro denominado “simples” que não incorpora a variação na deposição de linhas de crescimento no animal e entre animais, já o segundo modelo, denominado “hierárquico” faz essa incorporação. O modelo hierárquico obteve melhor ajuste aos dados de tamanho (CCC – comprimento curvilíneo da carapaça) e diâmetro do úmero, provavelmente devido a experiências desses répteis em ambientes com condições estocásticas, portanto alguns indivíduos podem crescer mais do que outros. A estimativa da duração do estágio oceânico foi de 8 a 19 anos (com média de 11,5) e a idade de maturação de 25,7 a 39,2 anos (com média de 31,2 anos). O modelo de crescimento de Schnute se ajustou bem aos dados de tamanho (CCC) e idade, devido sua versatilidade em forma e não requerimento de dados de tamanho de animais neonatais e de adultos próximos ao tamanho assintótico. Entretanto, a “curva” de Schnute foi bastante similar a uma reta, portanto foi ajustada uma regressão linear que obteve um melhor ajuste aos dados, que por sua vez, é composto por uma “janela de idade” do ciclo de vida das tartarugas marinhas. A “Hipótese de proporcionalidade corporal” foi aplicada para o cálculo das taxas de crescimento. As taxas de crescimento das tartarugas-cabeçudas neríticas foram similares as reportadas para tartarugas-cabeçudas do Atlântico Norte, porém menores do que as tartarugas oceânicas do Atlântico Sul. Sugerindo que as condições ambientais locais podem influenciar na taxa de crescimento da tartaruga marinha, como também, a energia gasta durante migrações, alocação de energia e origem genética. / The juvenile and sub-adult stages of loggerhead sea turtles (Caretta caretta) are poorly studied in Brazil. We present age estimates and a growth model for loggerhead sea turtles in the South Atlantic Ocean obtained through skeletochronological analysis of humeri obtained from both neritic and oceanic stage individuals. Since it was validated that each increment growth corresponds to one year for loggerhead sea turtle, the number of lines of arrested growth (LAGs) was taken as the age estimated. For larger turtles a correction factor was applied to solve for lost LAGs. This correction factor was based on two models, the first denoted “naïve” makes no distinction between inter- and intra-individual variability and the second denoted “hierarchical”, takes this distinction into account. The hierarchical model had the best fit to the data set, probably because these reptiles experience stochastic conditions through their life cycle, so that some individuals may grow more than others. The estimated ages indicate that the duration of the pelagic stage is 8 to19 years (average 11.5 years) and the age at maturation ranges from 25.7 to 39.2 years (average 31.2 years). Schnute‟s growth model was fit to age-at-length data, due to its versatility in shape and no requirement of size data for hatchlings up to individuals at old ages with near asymptotic size. However, since the shape of Schnute`s curve was almost linear for the age-window comprising our data, a linear regression ultimately yielded a slightly better fit. The “Body Proportional Hypothesis” was incorporated in the calculation of growth rates. Growth rates from neritic stage South Atlantic loggerheads were similar to those reported for neritic loggerhead sea turtles from the North Atlantic, but lower than for oceanic loggerheads from South Atlantic. This finding suggests that local environmental conditions influence turtle‟s growth rates, as well as, the energy expenditure during migrations, energy allocation and genetic origin.