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Characterization of Habitat for Hawksbill Turtle (Eretmochelys imbricata) in Los Roques Archipelago National Park, VenezuelaHunt, Luciana E. 2009 August 1900 (has links)
Information on the locations for feeding, reproductions, and resting, are essential
to effectively protect sea turtle populations and implement conservation efforts. This
type of ecological information is critically important for hawksbill turtle conservation in
Los Roques Archipelago National Park (LRANP) where turtles have been declining in
spite of habitat protection efforts. The goal of this research was to produce a benthic
habitat map of LRANP employing in situ visual surveys, remote sensing and geographic
information system techniques, and to spatially characterize sea turtle occupancy and
patterns of usage by habitat type. Between June and August of 2008, turtle behavior and
habitat use were recorded during 159 h of observation, comprising 46 sighting events (n
= 20 juveniles, n = 26 female adults). Observed activities were grouped into 4
categories: foraging, resting, swimming, and reproductive behavior. The benthic habitat
at each turtle sighting was recorded as one of three categories: coral reef, sand or marine
vegetation. Results suggest that the population of turtles within LRANP is comprised
primarily of female adults and juvenile individuals and that coral reef is the most
important habitat for this species. The most important foraging area in the atoll is a coral patch reef that connects Dos Mosquises Sur and Dos Mosquises Norte. The data in this
thesis have been made available in digital and map form to the managers of LRANP for
management purposes.
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Leptina e grelina na regulação do comportamento alimentar da tartaruga Eretmochelys imbricata (Linnaeus 1766) / Leptin and ghrelin regulates the feeding behavior of the sea turtle Eretmochelys imbricata (Linnaeus, 1766)Daphne Wrobel Goldberg 28 January 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Durante a temporada de nidação, fêmeas de tartarugas marinhas costumam reduzir ou cessar por completo a ingestão de alimentos. Este fato sugere que o armazenamento de energia e nutrientes para a reprodução ocorra durante o período que antecede a migração para os sítios reprodutivos, enquanto estes animais ainda se encontram nas áreas de alimentação. Do ponto de vista fisiológico, tartarugas em atividade reprodutiva são capazes de permanecer longos períodos em jejum. Fatores neuroendócrinos vêm sendo recentemente apontados como os mais relevantes para a manutenção da homeostase energética de todos os vertebrados; entre eles, a leptina (hormônio anorexígeno) e a grelina (peptídeo orexígeno). Com o objetivo de compreender o mecanismo de fome e saciedade nas tartarugas marinhas, investigamos os níveis séricos destes hormônios e de outros indicadores nutricionais em fêmeas de Eretmochelys imbricata desovando no litoral do Rio Grande do Norte, Brasil. Foram coletadas amostras de sangue de 41 tartarugas durante as temporadas reprodutivas de 2010/2011 e 2011/2012. Os níveis séricos de leptina diminuíram significativamente ao longo do período de nidação, de modo a explicar a busca por alimentos ao término da temporada. Ao mesmo tempo, registramos uma tendência crescente nos níveis séricos de grelina, fator este que também justifica a remigração para as áreas de alimentação no fim do período. Não foram observadas tendências lineares para alguns dos parâmetros avaliados, entre eles: hematócrito, alanina aminotransferase (ALT), aspartato aminotransferase (AST), fosfatase alcalina (FA), gama glutamil transferase (GGT), lipoproteínas de baixa densidade (LDL) e lipoproteínas de alta densidade (HDL). É possível que a maior parte dos indicadores nutricionais tenha apresentado redução gradativa devido ao estresse fisiológico decorrente da vitelogênese e de repetidas oviposições. No entanto, é valido ressaltar que o quadro de restrição calórica por tempo prolongado é o principal responsável pelas alterações em índice de massa corpórea e padrões bioquímicos nestes animais. / Reproductive female sea turtles rarely have been observed foraging during the nesting season. This suggests that prior to their reproductive migration to nesting beaches, the adult females must store sufficient energy and nutrients at their foraging grounds, and must be physiologically capable of undergoing months without feeding. Leptin (an appetite-suppressing protein) and ghrelin (a hunger-stimulating peptide) affect body weight by influencing energy intake in all vertebrates. We investigated the levels of these hormones and other physiological and nutritional parameters in nesting female hawksbill sea turtles in Rio Grande do Norte State, Brazil, by collecting consecutive blood samples from 41 turtles during the 2010/2011 and 2011/2012 reproductive seasons. We found that levels of serum leptin decreased over the nesting season, which potentially relaxed appetite suppression and led females to begin foraging either during or after the post-nesting migration. Concurrently, we recorded an increasing trend in ghrelin, which stimulated appetite towards the end of the nesting season. Both findings are consistent with the prediction that post-nesting females will begin to forage, either during or just after their post-nesting migration. We observed no seasonal trend for other physiological parameters: PCV values, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) low-density lipoprotein (LDL) and high-density lipoprotein (HDL) serum levels. The observed downward trends in general serum biochemistry levels were likely due to the physiological stress of vitellogenesis and nesting in addition to limited energy resources and probable fasting.
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Leptina e grelina na regulação do comportamento alimentar da tartaruga Eretmochelys imbricata (Linnaeus 1766) / Leptin and ghrelin regulates the feeding behavior of the sea turtle Eretmochelys imbricata (Linnaeus, 1766)Daphne Wrobel Goldberg 28 January 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Durante a temporada de nidação, fêmeas de tartarugas marinhas costumam reduzir ou cessar por completo a ingestão de alimentos. Este fato sugere que o armazenamento de energia e nutrientes para a reprodução ocorra durante o período que antecede a migração para os sítios reprodutivos, enquanto estes animais ainda se encontram nas áreas de alimentação. Do ponto de vista fisiológico, tartarugas em atividade reprodutiva são capazes de permanecer longos períodos em jejum. Fatores neuroendócrinos vêm sendo recentemente apontados como os mais relevantes para a manutenção da homeostase energética de todos os vertebrados; entre eles, a leptina (hormônio anorexígeno) e a grelina (peptídeo orexígeno). Com o objetivo de compreender o mecanismo de fome e saciedade nas tartarugas marinhas, investigamos os níveis séricos destes hormônios e de outros indicadores nutricionais em fêmeas de Eretmochelys imbricata desovando no litoral do Rio Grande do Norte, Brasil. Foram coletadas amostras de sangue de 41 tartarugas durante as temporadas reprodutivas de 2010/2011 e 2011/2012. Os níveis séricos de leptina diminuíram significativamente ao longo do período de nidação, de modo a explicar a busca por alimentos ao término da temporada. Ao mesmo tempo, registramos uma tendência crescente nos níveis séricos de grelina, fator este que também justifica a remigração para as áreas de alimentação no fim do período. Não foram observadas tendências lineares para alguns dos parâmetros avaliados, entre eles: hematócrito, alanina aminotransferase (ALT), aspartato aminotransferase (AST), fosfatase alcalina (FA), gama glutamil transferase (GGT), lipoproteínas de baixa densidade (LDL) e lipoproteínas de alta densidade (HDL). É possível que a maior parte dos indicadores nutricionais tenha apresentado redução gradativa devido ao estresse fisiológico decorrente da vitelogênese e de repetidas oviposições. No entanto, é valido ressaltar que o quadro de restrição calórica por tempo prolongado é o principal responsável pelas alterações em índice de massa corpórea e padrões bioquímicos nestes animais. / Reproductive female sea turtles rarely have been observed foraging during the nesting season. This suggests that prior to their reproductive migration to nesting beaches, the adult females must store sufficient energy and nutrients at their foraging grounds, and must be physiologically capable of undergoing months without feeding. Leptin (an appetite-suppressing protein) and ghrelin (a hunger-stimulating peptide) affect body weight by influencing energy intake in all vertebrates. We investigated the levels of these hormones and other physiological and nutritional parameters in nesting female hawksbill sea turtles in Rio Grande do Norte State, Brazil, by collecting consecutive blood samples from 41 turtles during the 2010/2011 and 2011/2012 reproductive seasons. We found that levels of serum leptin decreased over the nesting season, which potentially relaxed appetite suppression and led females to begin foraging either during or after the post-nesting migration. Concurrently, we recorded an increasing trend in ghrelin, which stimulated appetite towards the end of the nesting season. Both findings are consistent with the prediction that post-nesting females will begin to forage, either during or just after their post-nesting migration. We observed no seasonal trend for other physiological parameters: PCV values, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT) low-density lipoprotein (LDL) and high-density lipoprotein (HDL) serum levels. The observed downward trends in general serum biochemistry levels were likely due to the physiological stress of vitellogenesis and nesting in addition to limited energy resources and probable fasting.
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Aspectos da biologia reprodutiva de Eretmochelys imbricata (testudines, cheloniidae) no litoral sul do Rio Grande do Norte, Brasil / Change in the body weight of adult female hawksbill turtles during the 2006/2007 nesting season, on the southeast coast of Rio Grande do Norte state, BrazilSantos, Armando Jos? Barsante 27 May 2008 (has links)
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Previous issue date: 2008-05-27 / Female hawksbill turtles (Eretmochelys imbricata) nesting along the southeastcoastline of Rio Grande do Norte State, Brazil (6?13'40"S, 35?03'05"W) were captured and
weighed during the four months from January to April 2007, in the course of the annual egglaying season, which extended from 06 rd November 2006 to 30 rd May 2007. In all, 99 weight measurements were performed. On first contact the females exhibited an average
post-oviposition weight of 79.1 kg (range 56.2-98.9 kg, SD = 10.9 kg, n = 44 females). Those individuals which were subsequently recaptured showed a mean weight loss of 1.7 kg (range 0.7-4.5 kg, SD = 1.0 kg, n = 39 sets of measurements on 20 females) in the interval between
two consecutive post-ovipositions, separated by a maximum time interval of 17 days. In the cases where the female aborted the nesting process, the pre-oviposition weight was measured. The clutch weight, that is to say, the weight loss between consecutive pre-oviposition and
post-oviposition measurements (separated by a maximum time interval of 3 days), was found to be 5.2 kg (range 4.3-6.0 kg, SD = 0.9 kg, n = 6 sets of measurements). This value is significantly higher (t-test, p<0.001) than the loss between two consecutive post-oviposition
measurements with the same female. The mean recovery in body weight, that is to say, the average gain in weight between successive post-oviposition and pre-oviposition captures of the same individual (separated by a time interval of 12 to 17 days), was found to be 3.0 kg
(range 1.9-4.3 kg, SD = 1.0 kg, n = 4 sets of measurements) Although the small sample size makes it unwise to generalise, the recovery in body weight was found to be always significantly lower (t-test, p<0.005) than the clutch weight. This fact is in agreement with the
observed weight loss tendency throughout the breeding season for this species. Considering the clutch weight and the internidal recovery in body weight we found that the total weight loss of the adult hawksbill females after three to five nesting events varied from 10.4% (range
8.7-11.9%, SD = 1.6%, n = 3) to 14.1% (range 11.8-15.4%, SD = 1.3%, n = 6) in relation to their initial pre-oviposition weight. If there were no body weight recovery during the internesting interval we estimate that a female that nests three to five times in the course of
the season would lose from 19% to 31% of its initial weight. We emphasise that our clutch weight estimate was performed by weighing the females and not by multiplying the number of eggs in the nest by their average unit weight. In this way, our measurements take into account the loss of liquid during the oviposition. Despite the unequivocal evidence of body weight recovery during the internidal interval, it is not clear if the cause of this process is rehydration or feeding / Os dados que comp?em esta disserta??o, est?o organizados em dois cap?tulos que correspondem a dois artigos cient?ficos a serem submetidos ? publica??o. O primeiro, Body weight and energy budget of gravid hawksbill turtles (Eretmochelys imbricata) during the
nest season est? sendo submetido ao Journal of Herpetology e o segundo intitulado Prefer?ncias individuais por local de desova em Eretmochelys imbricata (LINNAEUS,
1756), na Praia de Pipa, Tibau do Sul, RN
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Contribui??o ? citogen?tica de testudines e an?lise de assimetria flutuante em Eretmochelys imbricata, CheloniidaeMarinho, Layse Aranha 08 July 2011 (has links)
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Previous issue date: 2011-07-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work has contributed to knowledge of the order Testudines from cytogenetic and morphological point of view. With regard to the aspects proposed cytogenetic characterization of the species Mesoclemmys tuberculata (n = 5), endemic to the Caatinga biomes, through conventional techniques of cytogenetics and molecular levels. This species presented 2n = 58, NF = 64, the first submetacentric pair, the second metacentric and third subtelocentric, and the other microchromosome telocentric. This species showed a nucleolar bearing pair, coincident with the 18S ribosomal rDNA and that proved to be heterochromatic. Small heterochromatic blocks were also found in the centromeres of the largest chromosomes, as well as terminal regions in most other chromosomes of the complement, that were GC +. Telomeric sequences showed variable patterns of signal intensity, with some repeats more intense in microchromosomes and subtly in the larger ones. When compared with other species of the genus, the G-banding patterns showed a marked similarity between them. The first karyotypic description of the species will aid in future studies and the understanding of evolutionary aspects of this family. From the morphological point of view, we carried out studies of fluctuating asymmetry in sea turtle Eretmochelys imbricata, using methods of benchmarking between hatchlings and adults and their implications for natural selection. Data were collected at two different times: first during the spawning female and the second during the outbreak and birth of the nest. The analyzed characteristics consisted of measurements of length and width of front and rear flippers (CANT, LANT, CPOS and LPOS) also collected data on the number of hull plates, side plates (NPL), the surrounding plates (NPCIRC), and plastron; plates power plants (NPP), inframarginais plates (NPIM). With the values of asymmetry we calculated the value of strict heritability for these traits, the calculation was based on only one parent. A nonparametric analysis Mann-Whitneywas performed to compare the groups (females X hatchlings, newborn hatchlings X dead hatchlings). Adult females showed no bilateral fluctuating asymmetry (FA = 0) on the number plates of the hull and plastron, while offspring, living and dead, showed a greater level of variation in these meristic parameters. In the analysis of females x hatchlings we found a significant difference between the levels of asymmetry in hoof plates (p=0.006) an the width of hindlimbs (p=0.001). Levels of FA suggest an accurate indicator as to the viability or maintenance of the individual to the reproductive phase. The coefficient of heritability (h2) of FA , obtained from the regression analysis, showed that both have low and not statistically significant values(p> 0.1). In the case of exclusion of the effective role of genetics in the generation of FA, reproductive strategies based on high number of subsidiaries products, such as those observed in E. imbricata seems to implicate the production of individuals with high level of developmental instability / O presente trabalho procurou contribuir ao conhecimento da ordem Testudines sob o ponto de vista citogen?tico e morfol?gico. No que diz respeito aos aspectos citogen?ticos prop?s a caracteriza??o da esp?cie Mesoclemmys tuberculata (n=5), end?mica da caatinga, por meio de t?cnicas de citogen?tica convencional e molecular. Esta esp?cie apresentou 2n=58, NF=64, primeiro par submetac?ntrico, o segundo metac?ntrico e o terceiro subteloc?ntrico, sendo os demais micromossomos teloc?ntricos. Esta esp?cie apresentou um par portador nucleolar, detectado pela impregna??o do ?on prata e utiliza??o de sondas de DNAr 18S. que se mostrou heterocrom?tico. Pequenos blocos heterocrom?ticos tamb?m foram encontrados em regi?es centrom?ricas dos maiores cromossomos, assim como em regi?es terminais na maioria dos outros cromossomos do complemento, que se mostraram GC+. Seq??ncias telom?ricas mostraram padr?es vari?veis de intensidade de sinal, sendo que alguns repeats foram mais intensos nos micromossomos e de forma sutil nos maiores. Os padr?es de bandamento G quando comparadas com outras esp?cies do g?nero mostraram uma pronunciada similaridade entre ambas. A primeira descri??o cariot?pica na esp?cie auxiliar? em futuros estudos e compreendimento dos aspectos evolutivos desta fam?lia. Sob o ponto de vista morfol?gico, realizou-se estudos de assimetria flutuante em Eretmochelys imbricata, tartaruga marinha, atrav?s de m?todos de aferi??o comparativa entre filhotes e adultos e as suas implica??es na sele??o natural. Os dados foram coletados em dois momentos distintos: o primeiro no momento da desova da f?mea e o segundo na eclos?o dos ninhos e nascimento dos filhotes. As caracter?sticas analisadas consistiram em medidas de comprimento e largura de nadadeiras anteriores e posteriores (CANT, LANT, CPOS e LPOS), tamb?m coletados dados de n?mero de placas do casco; placas laterais (NPL), placas circundantes (NPCIRC) e plastr?o; placas centrais (NPP), placas inframarginais (NPIM). Com os valores de assimetria foi calculado o valor de herdabilidade estricto para essas caracter?sticas, com o calculo baseado em apenas um parental. Foi realizado um teste n?o param?trico de Mann-Whitneya partir das medidas repetidas comparando os grupos (f?meas X filhotes; rec?m-nascidos X natimortos). As f?meas adultas n?o apresentaram assimetria flutuante bilateral (AF=0) quanto ao n?mero de placas do casco e plastr?o, enquanto os filhotes, vivos e mortos, mostraram maior n?vel de varia??o quanto a estes par?metros mer?sticos. Na an?lise entre f?meas X filhotes encontrou-se diferen?a significativa entre os n?veis de assimetria para as caracter?sticas de n?mero de .placas do casco (p=0,006) e para a largura da nadadeira posterior (p=0,001) entre estes grupos. Os n?veis de AF sugerem um indicador eficiente quanto ? viabilidade ou manuten??o do indiv?duo at? a fase reprodutiva. Ao analisarmos o coeficiente de herdabilidade em sentido estrito (h2) da AF a partir da an?lises de regress?o observou-se que ambas apresentam valores baixos, e n?o significativo estatisticamente (p>0,1). Caso venha a ser exclu?do um papel mais efetivo dos efeitos gen?ticos na gera??o de AF, estrat?gias reprodutivas baseadas em elevado n?mero de produtos filiais, como os observados em E. imbricata parecem implicar na produ??o de indiv?duos com elevado n?vel de instabilidade do desenvolvimento
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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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Nesting Ecology and Conservation of Sea Turtles in the Saudi Arabian Red SeaTanabe, Lyndsey K. 11 1900 (has links)
In the Saudi Arabian Red Sea, two of the seven species of sea turtles are known to nest and forage along the coast, the hawksbill turtle (Eretmochelys imbricata) and the green turtle (Chelonia mydas). As a result of some life history characteristics, sea turtles are particularly vulnerable to anthropogenic impacts. Under Saudi Arabia’s Vision 2030 and the recent opening of its borders to recreational tourists, the country aims to develop several large-scale projects along the Red Sea coast, locally known as “giga-projects”. Thus, imminent pressures from coastal development highlight the urgency needed for multi-country cooperation in protecting sea turtles in the region.
This dissertation aims to establish some baseline data and protocols for future work to meet the data needs of the relevant conservation authorities in Saudi Arabia. In particular, this thesis contributes new and important information to some of the identified knowledge gaps for the Red Sea region, including sea turtle habitat use, threat assessment (plastic and heavy metal pollution), and evaluating hatching success. I used satellite telemetry to understand foraging home ranges of hawksbill and green turtles, post-nesting migrations, and inter-nesting habitat use of green turtles. Additionally, I used photo identification to understand the abundance and behavior of turtles at a Rabigh fringing reef, in the central Red Sea. I assessed two anthropogenic contaminants as a threat to Red Sea turtles: heavy metal contamination and plastic ingestion. Heavy metal concentrations in the sand were evaluated at the largest green turtle rookery in Saudi Arabia, Ras Baridi, which is located next to a cement factory. I also assessed the concentration of heavy metals in the tissues of dead hatchlings found at Ras Baridi. Additionally, I studied plastic ingestion in ten deceased turtles found along the Saudi Arabian Red Sea. In my last data chapter, I assessed the hatching success of green turtle nests, and investigated clutch relocation as a possible method of increasing success. The final chapter summarizes the results from this research in the context of the 2004 PERSGA Marine Turtle Conservation Plan, and provides possible conservation strategy recommendations to protect Red Sea turtles
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Ecologia e Conservação de Tartarugas Marinhas Através da Análise de Encalhes no Litoral ParaibanoPoli, Camila 28 July 2011 (has links)
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Previous issue date: 2011-07-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Five sea turtle species use the Brazilian coast for reproduction and feeding: loggerhead turtle (Caretta caretta), green turtle (Chelonia mydas), leatherback turtle (Dermochelys coriacea), olive turtle (Lepidochelys olivacea) and hawksbill turtle (Eretmochelys imbricata). These species are included in the threatened categories, as much globally, according to the Red List of Threatened Species, issued by the International Union for Conservation of Nature (IUCN), as regionally, according to the Livro Vermelho da Fauna Brasileira Ameaçada de Extinção, published by the Ministério do Meio Ambiente. Sea turtles naturally face a wide variety of stressors, both natural and anthropogenic, like diseases, predation by other animals, incidental capture in fishing artifacts, marine pollution and the hunt. Systematic data collection from stranded sea turtles can provide useful biological information, such as seasonal and spatial patterns in their occurrence, and mortality, age structure, sex ratio, diet, interannual variations associated with climatic or anthropogenic events, as well as possible mortality causes. Thus, this study aimed to examine sea turtle strandings on the coast of Paraíba State, from August 2009 to July 2010, emphasizing the observation of the occurrence of ingestion of anthropogenic debris. In this period, 124 strandings were recorded. The species observed were C. mydas (n = 106), E. imbricata (n = 15), L. olivacea (n = 2) and C. caretta (n = 1). Of the total strandings that could be measured (n = 122), only twelve individuals (9.7%) could be considered adults. In 20 individuals, synthetic anthropogenic debris were found inside the gastrointestinal tract and of these, in 13 individuals it was concluded that the death cause was the ingestion of these residues. In 43 individuals, other traces of human interactions were observed, such as injuries caused by entanglement in fishing lines or nets, collisions with vessels, direct contact with oil spills, and lesions caused by knives and harpoons. In 28.5% of the stranded turtles, the presence of external tumors was noted, suggestive of fibropapillomatosis. Moreover, in 9.7%, shark bite marks were observed. A significant difference was found in the occurrence of strandings between males and females, being that the females were more frequent. Also, a significant difference was found in the occurrence of strandings between the different seasons, being that in the spring/summer (dry season), the strandings were more frequent. The most worrying result of this study was the observation of human interactions in half of the strandings analyzed. Stranding monitoring is necessary along the whole coast of Brazil and, indeed, along those of the entire world, because it has a fundamental role in studies of the ecology, biology and conservation of these species, generating benefits for local action, directed to the major problems observed. / Cinco espécies de tartarugas marinhas utilizam a costa brasileira para reprodução e alimentação: a tartaruga cabeçuda (Caretta caretta), a tartaruga verde (Chelonia mydas), a tartaruga de couro (Dermochelys coriacea), a tartaruga oliva (Lepidochelys olivacea) e a tartaruga de pente (Eretmochelys imbricata). Estas espécies estão incluídas em categorias de ameaça, tanto mundialmente, de acordo com a lista vermelha de animais ameaçados de extinção da União Internacional para a Conservação da Natureza (IUCN), como regionalmente, de acordo com o Livro Vermelho da Fauna Brasileira Ameaçada de Extinção, do Ministério do Meio Ambiente. As tartarugas marinhas, naturalmente, encontram uma ampla variedade de estressores, tanto naturais quanto antrópicos, como doenças, predação por outros animais, captura incidental em artefatos de pesca, poluição marinha e a caça. A coleta sistemática de dados de tartarugas marinhas encalhadas pode fornecer informação biológica útil, como por exemplo, padrões sazonais e espaciais na ocorrência e mortalidade, estrutura etária, proporção sexual, dieta, variações interanuais associadas a eventos climáticos ou antropogênicos bem como as possíveis causas de mortalidade. O objetivo deste trabalho foi analisar os encalhes de tartarugas marinhas na costa do estado da Paraíba, no período de agosto de 2009 a julho de 2010, enfatizando a observação da ocorrência de ingestão de material antropogênico. Neste período foram registrados 124 encalhes. As espécies observadas foram C. mydas (n = 106), E. imbricata (n = 15), L. olivacea (n = 2) e C. caretta (n = 1). Do total de encalhes que puderam ser mensurados (n = 122), apenas doze indivíduos (9,7%) puderam ser considerados adultos. Em 20 indivíduos, foram encontrados resíduos antropogênicos sintéticos dentro do trato gastrointestinal e destes, em 13 indivíduos foi possível concluir que a causa da morte foi a ingestão destes resíduos. Em 43 indivíduos foram observados outros vestígios de interações humanas, como ferimentos provocados por emaranhamentos em linhas ou redes, ferimentos provocados por colisões com embarcações, contato direto com manchas de óleo e ferimentos provocados por facas e arpões. Em 28,5% das tartarugas encalhadas notou-se a presença de tumores externos sugestivos de fibropapilomatose. Em 9,7% foi possível observar marcas de mordidas de tubarões. Observou-se uma diferença significativa na ocorrência de encalhes entre machos e fêmeas, sendo que as fêmeas foram mais frequentes. Também verificou-se uma diferença significativa na ocorrência de encalhes entre as diferentes estações, sendo que no período de primavera/verão (estação seca) os encalhes foram mais frequentes. O resultado mais preocupante deste estudo foi a observação de evidências de interação com atividades antrópicas em metade dos encalhes analisados. O monitoramento de encalhes se faz necessário em toda a costa do Brasil e do mundo, pois este tem papel fundamental em estudos de ecologia, biologia e conservação destas espécies, gerando assim subsídios para ações locais e direcionadas aos principais problemas observados.
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Aspectos reprodutivos em tartarugas marinhas da bacia potiguar RN/CEFabr?cio, Mar?lia Anielle da Silva 19 December 2016 (has links)
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Previous issue date: 2016-12-19 / Existem no mundo apenas sete esp?cies de tartarugas marinhas. Dentre essas, h? registros de ocorr?ncia de cinco esp?cies no litoral do Brasil: Dermochelys coriacea, Chelonia mydas, Caretta caretta, Eretmochelys imbricata e Lepidochelys olivacea. De acordo com a Lista Vermelha da Uni?o Internacional para a Conserva??o da Natureza, todas as esp?cies de tartarugas marinhas existentes no Brasil se encontram amea?adas de extin??o. A maioria dos trabalhos relacionados a propor??o sexual desses r?pteis indicam um desequil?brio populacional, havendo um n?mero excessivo de f?meas. Assim, pesquisas sobre a biologia reprodutiva desses animais s?o extremamente necess?rias e importantes para conserva??o de gera??es futuras dessas esp?cies. Este trabalho tem como objetivo estudar diferentes aspectos morfohistol?gicos das g?nadas de machos e f?meas de tartarugas marinhas na Bacia Potiguar. Foram avaliados animais vivos e mortos, provenientes de encalhes entre as praias de Icapu?/CE e Cai?ara do Norte/RN, totalizando aproximadamente 300 km. Os animais encalhados mortos ou que vieram a ?bito na Base de Reabilita??o do Projeto Cet?ceos da Costa Branca-UERN foram necropsiados por uma equipe veterin?ria. As g?nadas foram coletadas e fixadas em formol a 10%, e posteriormente submetidas a prepara??o histol?gica, atrav?s das t?cnicas de Hematoxilina-Eosina, sendo analisadas em microsc?pio ?ptico. No per?odo de janeiro de 2011 a dezembro de 2015 foram registrados 3.960 encalhes de tartarugas marinhas na ?rea estudada. A amostra apresentou propor??o sexual de 3:1, com predom?nio de f?meas. Oitenta e cinco por cento dos animais registrados foram classificados como pertencentes a fase de desenvolvimento "juvenil". Foram analisadas microscopicamente 86 amostras de tecido gonadal, sendo 53 f?meas e 25 machos da esp?cie Chelonia mydas, 3 f?meas e 3 machos de Eretmochelys imbricata e 2 f?meas de Caretta caretta. Foi poss?vel estabelecer tr?s est?gios de matura??o gonadal: pr? pubescente, pubescente e maduro. O predom?nio das g?nadas analisadas foi de indiv?duos pr? pubescentes, com f?meas apresentando ov?citos homog?neos e machos com t?bulos semin?feros de pequeno di?metro com aus?ncia de espermatozoides. Os esp?cimes pr? pubescentes f?meas apresentaram comprimento curvil?neo da carapa?a (CCC) m?dio de 37,07 cm e os machos 38,68 cm; Pubescentes f?meas 77,04 cm e machos 89,92 cm, F?meas maduras com 101,35 cm e um indiv?duo macho maduro com 105 cm. Pesquisas sobre aspectos histol?gicos relacionados ao desenvolvimento ovariano e testicular de tartarugas marinhas s?o escassas, mas, os resultados obtidos est?o em concord?ncia com o que j? foi descrito. Considera-se a necessidade de continuidade de trabalhos como esse, associando os dados morfol?gicos e biom?tricos ?s an?lises histol?gicas para o melhor entendimento sobre a matura??o sexual das tartarugas marinhas e implementa??o de propostas de conserva??o para essas esp?cies. / Among the seven species of sea turtles, five occurs on the Brazilian coast: Dermochelys coriacea, Chelonia mydas, Caretta caretta, Eretmochelys imbricata e Lepidochelys olivacea. According to the Red List of the IUCN, all species of sea turtles in Brazil are endangered. The majority of works related that the sexual proportion of these animals indicate a population imbalance, having a number excessive of females. Thus, studies of reproductive biology of sea turtles are extremely necessary and important for the conservation of these species for future generations. This work aims to study different morphohistological aspects of male and female's gonads of sea turtle in Potiguar Basin. For this, were evaluated dead and living animals, from strandings between the beaches of Icapu?/CE and Cai?ara do Norte/RN, totaling approximately 300 km. The dead animals were necropsied. During the procedure, the gonads were collected and fixed in formalin 10%, then submitted to histological process, through the techniques of hematoxylin-eosin, according Tolosa (2005), being analyzed in an optical microscope. Between January 2011 and December 2015 were recorded 3.960 stranding of sea turtles in the study area. The sample showed sex ratio of 3:1, with a predominance of females. . Eighty-five percent of the animals were classified juvenile. 86 samples of gonadal tissue wereanalized microscopically, being 58 females and 28 males, of Chelonia mydas, Eretmochelys imbricata e Caretta caretta. It was possible to establish three stages of maturation: pre-pubertal, pubertal and mature. The predominance was of pre-pubertal individuals, females presenting homogeneous oocytes and males with seminiferous tubules with a small diameter with absence of sperm. The pre-pubertal females specimens exhibit an average of 37,07 cm (CCC) and the males 38,68 cm (CCC); Pubertal females with an average of 77,04 cm and males 89,92 cm; mature females with 101,9 cm (CCC) and a single mature male with 105 cm. Researches on histological aspects related to ovarian and testicular development of sea turtles are scarce, but, the obtained results are in agreement with what has already been described. Researches like this, associating morphological and biometric data to histological analyzes, are necessary for the best knowledge about sexual maturity of these animals and implementation of conservation proposals for these species.
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Foraging Ecology and Stress in Sea TurtlesChelsea E Clyde-Brockway (6823772) 13 August 2019 (has links)
As ectothermic marine megafauna, sea turtle physiology and ecology are tightly intertwined with temperature, seasonality, and oceanography. Identifying how turtles respond when exposed to cold water, how they adapt to cold environments when they need to explore cold environments in order to forage, and what foraging resources are exploited by sea turtles are all components central to their conservation. Cold-stunning is a well-documented phenomenon that occurs when water induced decreases in sea turtle body temperature cause turtles to become immobilized and wash ashore. While most cold-stunned turtles are rescued and rehabilitated, we do not know whether cold-stunning is an acute transient occurrence, or a symptom of a bigger environmental problem. Further, while in some environments avoiding cold water is preferential, in other habitats, sea turtles need to inhabit cold environments in order to forage. Along the Eastern Pacific Rim, discrete upwelling locations are characterized by high primary productivity and unusually cold water. In these environments, avoidance is not possible and sea turtles require physiological adaptions to mitigate body temperature decreases in cold water. Little is known about how turtles handle upwelling environments, despite the fact that sea turtles remain in these habitats regardless of water temperature fluctuations. Because upwelling habitats provide increased nutrient presence, and sea turtles are opportunistic foragers, quantification of diet composition will further our understanding of why sea turtles remain in cold water environments year-round. Diet composition in multiple populations of cohabitating sea turtles revealed partitioning that results in reduced inter-specific competition. Further, flexibility in diets provides a wide range of ecosystem services central to habitat resiliency. Therefore, conservation of endangered sea turtles requires complete ecosystem conservation, and complete understanding of the interconnectivity of sea turtles and their environments is crucial.<br>
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