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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Stabel Isotope Turnover Rates And Diet-tissue Discrimination In The Skin Of West Indian Manatees: Implcations For Evaluating Their Feeding Ecology And Habitat Use

Alves, Christy 01 January 2007 (has links)
The West Indian manatee (Trichechus manatus) is an herbivorous marine mammal that occupies freshwater, estuarine, and marine habitats. Despite being considered endangered, relatively little is known about the feeding ecology of either of the two recognized subspecies, the Florida manatee (T.m. latirostris) and Caribbean or Antillean manatee (T.m. manatus). A better understanding of their respective feeding preferences and habitat use is essential to establish criteria on which conservation plans can be based. The present study expands on previous work on manatee feeding ecology by both assessing the application of stable isotope analysis to manatee tissue and providing critical baseline parameters for accurate isotopic data interpretation. The present study was the first to calculate stable isotope turnover rate in the skin of any marine mammal. Stable carbon and nitrogen isotope ratios were examined over a period of more than one year in the epidermis of rescued Florida manatees that were transitioning from a diet of aquatic forage to terrestrial forage (lettuce) in captivity. Mean half-life for 13C turnover in manatee epidermis was 55 days and mean half-life for 15N turnover was 42 days. Due to these slow turnover rates, carbon and nitrogen stable isotope analysis in manatee epidermis is useful in summarizing average dietary intake over a long period of time rather than assessing recent diet. In addition to turnover rate, a diet-tissue discrimination value of 2.8‰ for 13C was calculated for long-term captive manatees on a lettuce diet. Turnover and diet-tissue discrimination results were subsequently used to interpret carbon and nitrogen stable isotope data in epidermis samples collected from free-ranging manatees in Florida, Belize, and Puerto Rico. This study was the first application of stable isotope analysis to Antillean manatees. Regional differences in stable isotope ratios in manatee skin were consistent with ratios in plant samples collected in those regions. Signatures in the skin of manatees sampled in Belize and Puerto Rico indicated a diet composed mainly of seagrasses, whereas those of Florida manatees exhibited greater variation. Mixing model results indicated manatees sampled from Crystal River and Homosassa Springs had an overall average intake of primarily freshwater vegetation whereas manatees sampled from Big Bend Power Plant, Ten Thousand Islands, and Warm Mineral Springs fed primarily on seagrasses. Possible diet tissue discrimination values for 15N ranged from 1.0 to 1.5‰. Stable isotope analysis can be successfully applied to interpret manatee feeding behavior over a long period of time, specifically the use of freshwater vegetation vs. seagrasses, and can aid in improving conservation efforts.
32

Phylogeny and Visual System Evolution in Sap Beetles (Coleoptera: Cucujoidea: Nitidulidae)

Powell, Gareth S. 10 December 2021 (has links)
Coleoptera is currently the most diverse lineage of life on Earth with more than 400,000 described species. The group also contains unbelievable ecological and morphological variation that has been evolving since the early Carboniferous (>350 MYA). The group provides the perfect playground to test evolutionary hypotheses with large-scale phylogenies. First, a newly developed bioinformatics tool is presented that allows for the critical assessment of the stability of phylogenetic nodes with even minor changes in taxon sampling (i.e. a single taxon jackknifed). The tool, TANOS, is capable of performing tests on large genomics-scale datasets. The case study included is a widely used phylogenomics effort to resolve the higher level relationships of all Insecta. The specific beetle group chosen for the remaining products is the superfamily Cucujoidea, and more specifically the family Nitidulidae, or sap beetles. Several taxonomic and nomenclatural projects were necessary to provide a more stable classification and begin the process of establishing the group as a model system for questions concerning feeding behavior evolution. Several new species of the genus Carpophilus were described from both the West Indies and the New World tropics and subtropics. Several type designations were also needed for many species in the subfamily Carpophilinae. In addition, the fossil diversity of Nitidulidae was reviewed with the addition of the oldest known member of the Cillaeinae from amber (Dominican). With the reviewed fossil fauna, as well as many more from across the Cucujoidea more broadly, a divergence-time estimated phylogeny was generated for >250 species of the superfamily. The phylogeny, based on the combination of multiple published Sanger datasets and supplemented with newly generated data for a further 50 species, was used to date multiple feeding shifts in the group. Specifically, the clade ages were used to compare with published clade ages for the corresponding food resource each clade is known to exploit. A significant relationship was recovered between age of the beetle clade and the corresponding food resource clade. Interestingly, it was found that clades that shifted to a food resource first, in the absence of existing beetle competitors, were significantly more diverse over subsequent lineages that shifted to the same resource. A feeding ecology of specific importance, at least to many groups of nitidulid, is anthophily, or flower-visiting. An extreme variation in eye size is observable across the family and so multiple factors including; sex, day-night activity, and feeding behavior were tested in a phylogenetic context. No sexual dimorphism nor variation consistent with activity period was found. Relative eye size of flower visiting species was significantly larger than that of all other feeding behaviors in sap beetles. This correlation was also tested in a phylogenetic context, with the increase in morphological investment in vision repeatedly shown to correspond to shifts in flower associated behavior. In an attempt to investigate the interplay between behavior, morphology, and genetics in the same process, opsin data was captured as part of a large targeted enrichment sequencing effort (AHE) across Nitidulidae and their relatives. The first phylogenomic estimate was generated for the group, with a taxon sampling of 192, and data sampling depth of 703 loci. A newly updated pipeline was developed for AHE data and is presented herein. Topological results support the recent idea of a non-monophyletic Cucujoidea. Results also demonstrate multiple classification issues within the Nitidulidae with several new subfamilies/tribes necessary to maintain diagnosable monophyletic groups in the family. The vast majority of sampled genera were supported, with the exception of Brachypeplus and Pallodes. Preliminary opsin diversity across the group is much greater than previously estimated. Opsin copy number is potentially plastic even within individual genera, although consistently duplications are associated with taxa that visit flowers. It is clear that the complexity of cucujoid visual systems increases with anthophilous behavior.
33

Feeding competition in Japanese macaques in Yakushima: effects of intergroup hostility and group size / 屋久島のニホンザルにおける採食競合:群間関係および群れサイズの影響

Kurihara, Yosuke 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20217号 / 理博第4302号 / 新制||理||1618(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 半谷 吾郎, 教授 湯本 貴和, 教授 平井 啓久 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
34

Ontogenetic resource partitioning in white-faced sakis (Pithecia pithecia)

Robl, Nicholas 04 December 2008 (has links)
No description available.
35

Reconstructing the Paleodiet of Ground Sloths Using Microwear Analysis

Resar, Nicholas A. 15 May 2012 (has links)
No description available.
36

Feeding ecology of black and white colobus monkeys from south coastal Kenya: the influence of spatial availability, nutritional composition, and mechanical properties of food items

Dunham, Noah T. 27 June 2017 (has links)
No description available.
37

Socioecology, stress, and reproduction among female Diana monkeys (<i>Cercopithecus diana</i>) in Cote d’Ivoire’s Tai National Park

Kane, Erin Elizabeth January 2017 (has links)
No description available.
38

Déprédation par les orques (Orcinus Orca) et les cachalots (Physeter Macrocephalus) sur les palangriers à la legine australe dans la ZEE de l' archipel de Crozet

Tixier, Paul 10 July 2012 (has links)
C'est dans le contexte délicat du milieu marin, marqué par l'écroulement des stockshalieutiques et la conservation urgente des espèces de prédateurs marins, que s'inscrit cette étude sur la déprédation (i.e. prélèvement des poissons capturés) par les orques et les cachalots sur la pêche à lapalangre dans la ZEE de l'Archipel de Crozet.Le premier objectif a été d'évaluer les conséquences socio-économiques du phénomène. Entre 2003 et2010 les orques ont interagi avec un total de 43,3% des palangres relevées et les cachalots avec 57,5%,les deux espèces étant présentes simultanément sur 27.8% des palangres (n=5438). Les orques, seulesou associées aux cachalots ont été estimées prélever 926 ± 76 tonnes de légines sur l'ensemble de lapériode, représentant un taux de déprédation de 17,7%.Trois facteurs opérationnels ont été identifiés comme faisant varier la déprédation par les orques : i)utilisation de palangres courtes (<5000m) en absence d'orques, ii) déplacement du navire sur desdistances supérieures à 40nq pour quitter une zone confrontée à la déprédation et changer de zone, iii)utilisation de vitesse de remontée des hameçons à bord supérieures à 50 H.min-1.Le deuxième objectif de cette étude a été d'évaluer les conséquences démographiques de ladéprédation sur la population d'orques de Crozet. Le suivi à long terme des individus a permis demettre en évidence des réponses différentielles des unités sociales en fonction de leur degréd'interaction avec les pêcheries. / Over the last 50 years, fisheries have undergone a major decline worldwide. With an increasedcompetition for resource, depredation (i.e. removal of catches on fishing gear) has recently become amajor case of conflict between humans and marine predators. In this study I focused on thedepredation on Patagonian toothfish fisheries by killer and sperm whales in the Crozet EEZ. The firstpart of the study aimed at assessing the socio-economic consequences of this issue. Killer and spermwhales have interacted with 43.3% and 57.5% of longlines (n=6751) respectively from 2003 to 2010.Killer whales, alone or co-occurring with sperm whales were responsible for an estimated loss of 926± 76 tons of toothfish over that period, which represents 17.7% of the total catch.Three operational factors were identified as influencing significantly depredation levels: i) the use ofshort longlines (<5000m) in absence of killer whales, ii) the displacement of vessels on distances>40nq to leave the whales behind and iii) the use of longline hauling speed > 50 H.min-1.The second aim of the study was to investigate the consequences of depredation on the Crozet killerwhale population. The long term monitoring of individuals showed divergent demographic trajectoriesrelated to the depredation level of matrilines. During the 1990s, matrilines interacting with fisherieshave undergone a high mortality due to lethal interactions with illegal fishing vessels using explosivesto repel the whales.
39

Ecologia Alimentar do gavião-do-rabo-branco Buteo albicaudatus (Falconiformes:Accipitridae) no município de Juiz de Fora, sudeste do estado de Minas Gerais. / Feeding ecology of the White-tailed Buteo albicaudatus (Falconiformes:Accipitridae) in the Juiz de Fora municipality, southeast Minas Gerais State

Granzinolli, Marco Antonio Monteiro 16 September 2003 (has links)
Este estudo apresenta dados sobre a ecologia alimentar do gavião-do-rabo-branco (Buteo albicaudatus albicaudatus) no município de Juiz de Fora, sudeste do estado de Minas Gerais. Os objetivos específicos foram: a) estudar quantitativamente a dieta do gavião-do-rabo-branco, incluindo número de presas e biomassa consumida; b) analisar possíveis padrões de sazonalidade na dieta; c) determinar a amplitude de nicho trófico do gavião-do-rabo-branco; d) verificar a existência de possíveis respostas numéricas e funcionais na dieta desse gavião e e) verificar estatisticamente as prévias proposições de oportunismo na escolha de presas por esse predador sugeridas por Stevenson & Meitzen (1946), Farquhar (1986) e Kopeny (1988). O material para estudo da dieta do B. albicaudatus consistiu de pelotas de regurgitação, coletado simultaneamente com os dados de abundância dos principais grupos de presas e do predador na área de estudo. As 259 amostras analisadas revelaram 31 espécies/morfoespécies e uma biomassa total estimada de 7196,5 g. Cinco ordens de insetos (Hymenoptera, Heteroptera, Odonata, Isoptera e Lepidoptera) e uma de vertebrado (Chiroptera) são descritas pela primeira vez como integrantes da dieta de B. albicaudatus. Numericamente, os invertebrados representaram 88% da dieta, sendo Acrididae responsável por 63% da dieta total. Dentre os vertebrados, os roedores foram o grupo mais consumido (73% da classe e 8% da dieta total). Analisando-se as presas em relação à biomassa, verificou-se uma brusca inversão na maioria das espécies/morfoespécies. Nesta abordagem, os vertebrados corresponderam a 77% da dieta. Os grupos mais representativos são: roedores (50%), ortópteros (21%), aves (11%), lagartos (7%) e serpentes (5%). A análise de sazonalidade na dieta mostrou uma evidente dependência de consumo quanto à estação climática, em mais da metade das categorias. Na estação seca verifica-se um maior consumo de Araneomorphae, outros artrópodes e mamíferos, enquanto na estação chuvosa, o maior consumo foi registrado para Acrididae e Coleoptera. Aves e répteis, apesar de não apresentarem uma dependência significativa em relação à sazonalidade, parecem ser utilizados como complemento ao consumo de mamíferos na estação chuvosa, no que tange a biomassa ingerida. Buteo albicaudatus pode ser classificado como insetívoro, em termos de número, ou como carnívoro, em termos de biomassa ingerida. A amplitude trófica da dieta mostrou-se de intermediária para baixa, variando de acordo com a abordagem adotada. Em termos gerais, quanto ao número e a biomassa, a dieta total mostrou que o gavião-do-rabo-branco é especialista. No entanto, a análise da biomassa referente a cada estação climática revelou que na estação chuvosa, a dieta é intermediária entre generalista e especialista (Bp itens=0,292; Bp grupos=0,485). Esses dados indicam que tanto o consumo de determinados itens alimentares quanto a amplitude de nicho trófico pode variar de acordo com a estação climática. Comparando-se a abundância do principal grupo de presa (pequenos mamíferos), em termos de biomassa, no ambiente e os registros de B. albicaudatus percebe-se que em nove dos doze meses há uma sincronia nas flutuações, caracterizando uma resposta numérica (rs=0,864; p<< 0,001). Resposta funcional foi registrada para a ordem Orthoptera (rs=0,762; p<0,01) e para a família Acrididae (rs=0,706; p<0,05). Com relação à seletividade de espécies de presas, observou-se que dos 12 gêneros de pequenos mamíferos capturados por armadilhas de interceptação e queda no ambiente, apenas cinco (Calomys, Akodon, Oligoryzomys, Oxymycterus e Gracilinanus) fazem parte da dieta de B. albicaudatus. Em relação a estes gêneros, o gavião-do-rabo-branco apresentou seletividade para Calomys tener e rejeição para Akodon spp apenas na estação seca. Os dados apresentados neste estudo sugerem que a abundância de pequenos mamíferos pode determinar o comportamento seletivo ou oportunismo de B. albicaudatus. No período de maior oferta de recurso há uma seletividade enquanto, no período de menor abundância de alimento, há um oportunismo por parte do predador. Este estudo revelou que o gavião-do-rabo-branco possui uma flexibilidade em sua dieta.
40

Caracterização da dieta da lontra neotropical (Lontra longicaudis, Carnivora: Mustelidae) em três rios de Mata Atlântica do Sul do Brasil: uma análise espacial e temporal / Characterization of diet Neotropical otter (Lontra longicaudis, Carnivora: Mustelidae) in three rivers of the Atlantic Forest in southern Brazil: an analysis of spatial and temporal

Krepschi, Victor Gasperotto 10 August 2012 (has links)
Made available in DSpace on 2017-07-10T14:38:35Z (GMT). No. of bitstreams: 1 Victor.pdf: 806977 bytes, checksum: e9912520cdf34c3078242340bfd6d207 (MD5) Previous issue date: 2012-08-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The diet of Otter longicaudis was characterized by fecal analysis and spatial and temporal aspects in their main prey consumption were analyzed. The study was conducted systematically in three rivers of the Iguaçu National Park, an Atlantic forest reserve located in southern Brazil. For a year, samples were taken monthly along three sections totaling 46 km, in order to find fecal samples. The analysis of 367 fecal samples collected showed a piscivorous diet, which includes four main fish families: Characidae Cichlidae, Pimelodidae and Loricariidae, with consumption of crustacean belonging to the family Trichodactilidae. Mollusks, birds, mammals, reptiles and insects were found in the diet. Seeds, vegetable fibers and materials of anthropogenic origin were also found. Differences in diet composition were found between the Iguaçu River and the other, which is probably related to the physical characteristics of these rivers reflecting distinct prey items available. The crabs were used as complementary resources for neotropical otters, when the consumption of their main prey (fish) decreased. An increased frequency of occurrence of prey categories was recorded in spring and summer, except for crabs and molluscs in two of the three rivers, which contrasts with the high consumption of fish during all seasons. Correlation was found between precipitation and consumption of fish families, which in turn seems to be due changings and the river otter and the habits of those arrested. In this region, otters depend on the features of the aquatic environment, forecasting the Mayor attention to the maintenance of rivers, shores and natural features (such as flow regimes and water), especially the river Gonçalves Dias, borders the east side of the National Park Iguaçu, with areas of heavy anthropogenic land use / A dieta de Lontra longicaudis foi caracterizada por análise fecal e aspectos espaciais e temporais no consumo de suas presas principais foram analisados. O estudo foi realizado sistematicamente em três rios do Parque Nacional do Iguaçu, uma reserva de Mata Atlântica localizado no sul do Brasil. Durante um ano, foram amostragens realizadas mensalmente ao longo de três trechos, totalizando 46 km, a fim de encontrar amostras fecais. A análise de 367 amostras fecais coletadas apresentaram uma dieta piscívoro, que inclui quatro principais famílias de peixes: Characidae, Cichlidae, Pimelodidae e Loricariidae, com consumo de crustáceo pertencente à família Trichodactilidae. Moluscos, aves, mamíferos, répteis e insetos foram detectados na dieta. Sementes, fibras vegetais e materiais de origem antrópica também foram encontradas. Diferenças na composição da dieta foram encontradas entre rio Iguaçu e os outros, que provavelmente está relacionado com as características físicas desses rios refletindo distinta presa disponibilidade itens. Os caranguejos foram utilizados como recursos complementares para as lontras neotropicais, quando o consumo de sua principal presa (peixes) diminuiu. Uma freqüência aumentado da ocorrência de categorias de presas foi registrada na primavera e no verão, com exceção de caranguejos e moluscos, em dois dos três rios, o que contrasta com o elevado consumo de peixes ao longo todas as estações. Correlação foi encontrada entre a precipitação eo consumo de famílias de peixes, o que por sua vez parece ser changings devido o rio e os hábitos da lontra e essas presas. Nesta região, as lontras dependem dos recursos do ambiente aquático, prevendo a atenção prefeito para a manutenção dos rios, margens e características naturais (como fluxo e regimes de água), em especial do rio Gonçalves Dias, fronteiras do leste lado do Parque Nacional do Iguaçu, com áreas de uso da terra pesada antrópica

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